Friday, August 31, 2018

Lockheed Martin begins final assembly on NASA's Orion

Technicians have completed construction on the spacecraft capsule structure that will return astronauts to the Moon, and have successfully shipped the capsule to Florida for final assembly into a full spacecraft. The capsule structure, or pressure vessel, for NASA's Orion Exploration Mission-2 (EM-2) spacecraft was welded together over the last seven months by Lockheed Martin technicians and engineers at the NASA Michoud Assembly Facility near New Orleans. Orion is the world's only exploration-class spaceship, and the EM-2 mission will be its first flight with astronauts on board, taking them farther into the solar system than ever before. "It's great to see the EM-2 capsule arrive just as we are completing the final assembly of the EM-1 crew module," said Mike Hawes, Lockheed Martin vice president and program manager for Orion. "We've learned a lot building the previous pressure vessels and spacecraft and the EM-2 spacecraft will be the most capable, cost-effective and efficient one we've built." Orion's pressure vessel is made from seven large, machined aluminum alloy pieces that are welded together to produce a strong, light-weight, air-tight capsule. It was designed specifically to withstand the harsh and demanding environment of deep space travel while keeping the crew safe and productive.


"We're all taking extra care with this build and assembly, knowing that this spaceship is going to take astronauts back to the Moon for the first time in four decades," said Matt Wallo, senior manager of Lockheed Martin Orion Production at Michoud.

"It's amazing to think that, one day soon, the crew will watch the sun rise over the lunar horizon through the windows of this pressure vessel. We're all humbled and proud to be doing our part for the future of exploration."

The capsule was shipped over the road from New Orleans to the Kennedy Space Center, arriving on Friday, Aug. 24. Now in the Neil Armstrong Operations and Checkout Building, Lockheed Martin technicians will immediately start assembly and integration on the EM-2 crew module.

Thursday, August 30, 2018

China tests propulsion system of space station's lab capsules

Engineers have successfully tested the propulsion system of China's planned space station lab capsules, a key step in its space station program.Weighing 66 tonnes, the space station will comprise a core module and two lab capsules. The propulsion system will determine whether lab capsules can move in space. Engineers designed 36 engines for the propulsion system with four to adjust the capsules' operation orbit and 32 to adjust flight attitude. Each engine is designed to work for at least 15 years, according to the China Aerospace Science and Technology Corporation (CASC), the main manufacturer of the space station. The engines worked well and passed tests in Shanghai, said the CASC. China is accelerating its timetable for the Tiangong space station, with the Tianhe core capsule expected to be launched in 2020. The station is due for completion around 2022.


Wednesday, August 29, 2018

Lockheed's first GPS III satellite shipped to Florida for launch

The first of the U.S. Air Force's new advanced, high power GPS III satellites has shipped to Cape Canaveral for its projected launch in December. The satellite was shipped from Buckley Air Force Base in Colorado to the Cape on August 20 on an Air Force C-17 cargo aircraft, Lockheed Martin announced on Monday. GPS III will have three times better accuracy and up to eight times improved anti-jamming capabilities, according to Lockheed. The new L1C civil signal also will make it compatible with other international global navigation satellites. Lockheed has been selected to build the first 10 of satellites for a new GPS constellation. The first in the series is being prepared for its scheduled launch later this year, and the second has been declared ready for launch by Lockheed, though it has not been delivered to the Air Force yet. The third satellite is expected to be ready early next year -- Lockheed reports it has already completed its construction -- and the company has the fourth, fifth, sixth and seventh satellites at varying stages of progress. To date, more than 90 percent of parts and materials for all 10 satellites under contract have been received. Lockheed has also submitted a proposal to build up to 22 additional satellites to enhance capabilities to the GPS constellation.


"Once on orbit, the advanced technology of this first GPS III space vehicle will begin playing a major role in the Air Force's plan to modernize the GPS satellite constellation," Johnathon Caldwell, Lockheed Martin program manager for Navigation Systems, said in a statement.

"We are excited to start bringing GPS III's new capabilities to the world and proud to continue to serve as a valued partner for the Air Force's positioning, navigation and timing mission systems," Caldwell said.

Tuesday, August 28, 2018

JPL roles in NASA's Parker Solar Probe

The navigation for NASA's Parker Solar Probe is led by the agency's Jet Propulsion Laboratory in Pasadena, California, which also has a role in two of the spacecraft's four onboard instrument suites. Parker Solar Probe will fly closer to the Sun than any previous spacecraft and through the solar corona itself. One instrument, called the Energetic Particle Instrument-Hi (EPI-Hi), will investigate the mysteries of high-speed solar particles that hurtle toward Earth at close to the speed of light. Observations by the Parker Solar Probe will lead to better predictions of space weather and address fundamental mysteries about the Sun's dynamic corona. EPI-Hi is part of the Integrated Science Investigation of the Sun, led by Principal Investigator David McComas of Princeton University in New Jersey. "We will be exploring a region of space that has never before been visited," said Mark Wiedenbeck, the lead investigator on the EPI-Hi instrument and a principal research scientist at JPL. "We have ideas about what will be found, but the most important results may well come from observations that are completely unexpected." Of particular interest to the EPI-Hi team is the unsolved riddle of how a small fraction of the charged particles from the Sun reach near-light speeds. These particles, protons, electrons and heavy ions can reach Earth in less than an hour, creating space weather hazards to humans and hardware in space.


Until now, scientists had been observing from a distance the effects of what is happening near the Sun. With the Parker Solar Probe now on its way to fly through the region where it is happening, scientists are confident they will obtain new clues and insight into the process.

The EPI-Hi instrument consists of stacks of silicon detectors designed to snag high-speed particles and measure their energies. Some of the detectors are very thin, with the thinnest being about one-eighth the thickness of a standard sheet of paper. For the detectors to make the required measurements, the thickness of these detectors could vary by no more than one-hundredth the thickness of a sheet of paper.

Another instrument on Parker Solar Probe - the Wide-Field Imager for Solar Probe Plus (WISPR) - is the only camera aboard the spacecraft. It will take images of the Sun's corona and inner heliosphere.

The imager has two telescopes that will capture images of the solar wind, shock waves and other coronal structures as they approach and pass the spacecraft.WISPR provides a very wide field-of-view, extending from 13 degrees away from the center of the Sun to 108 degrees away.

"If you saw the solar eclipse last August, you saw the Sun's corona. That is our destination. WISPR will be taking images of the corona as it flies through it. The images will help us understand the morphology, velocity, acceleration and density of evolving solar wind structures when they are close to the Sun," said JPL scientist Paulett Liewer, a member of the WISPR Science Team. The WISPR principal pnvestigator is Russell Howard of the Naval Research Laboratory.

In leading Parker's navigation efforts, JPL is helping to implement the mission's innovative trajectory, developed by the Johns Hopkins Applied Physics Laboratory, Laurel, Maryland, which built and operates the spacecraft for NASA. The Parker Solar Probe will use seven Venus flybys over nearly seven years to gradually shrink its orbit around the Sun, coming as close as 3.83 million miles (6.16 million kilometers) to the Sun, well within the orbit of Mercury and about seven times closer to the Sun than any spacecraft before.

In addition, the Parker Solar Probe Observatory Scientist, Principal Investigator Marco Velli, a UCLA professor, holds a part-time appointment as Heliophysics Liaison to NASA at JPL.

The Parker Solar Probe lifted off on Aug. 12, 2018, on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex-37 at Cape Canaveral Air Force Station in Florida. The mission's findings will help researchers improve their forecasts of space weather events, which have the potential to damage satellites and harm astronauts on orbit, disrupt radio communications and, at their most severe, overwhelm power grids.

Monday, August 27, 2018

China launches new twin BeiDou navigation satellites

China on Saturday successfully sent twin BeiDou navigation satellites into space on a single carrier rocket. The Long March-3B carrier rocket lifted off from Xichang Satellite Launch Center in southwest China's Sichuan Province at 7:52 a.m.. It was the 283rd mission of the Long March rocket series, said a source of the launch center. The twin satellites entered orbit more than three hours after the launch. After a series of tests, they will work together with 10 other BeiDou-3 satellites already in orbit. The twin satellites were developed by the Innovation Academy for Microsatellites of the Chinese Academy of Sciences. Named after the Chinese term for the Big Dipper, the BeiDou system started serving China in 2000 and the Asia-Pacific region in 2012.




Saturday, August 25, 2018

Light from ancient quasars helps confirm quantum entanglement

Last year, physicists at MIT, the University of Vienna, and elsewhere provided strong support for quantum entanglement, the seemingly far-out idea that two particles, no matter how distant from each other in space and time, can be inextricably linked, in a way that defies the rules of classical physics. Take, for instance, two particles sitting on opposite edges of the universe. If they are truly entangled, then according to the theory of quantum mechanics their physical properties should be related in such a way that any measurement made on one particle should instantly convey information about any future measurement outcome of the other particle - correlations that Einstein skeptically saw as "spooky action at a distance." In the 1960s, the physicist John Bell calculated a theoretical limit beyond which such correlations must have a quantum, rather than a classical, explanation. But what if such correlations were the result not of quantum entanglement, but of some other hidden, classical explanation? Such "what-ifs" are known to physicists as loopholes to tests of Bell's inequality, the most stubborn of which is the "freedom-of-choice" loophole: the possibility that some hidden, classical variable may influence the measurement that an experimenter chooses to perform on an entangled particle, making the outcome look quantumly correlated when in fact it isn't.


Last February, the MIT team and their colleagues significantly constrained the freedom-of-choice loophole, by using 600-year-old starlight to decide what properties of two entangled photons to measure. Their experiment proved that, if a classical mechanism caused the correlations they observed, it would have to have been set in motion more than 600 years ago, before the stars' light was first emitted and long before the actual experiment was even conceived.

Now, in a paper published in Physical Review Letters, the same team has vastly extended the case for quantum entanglement and further restricted the options for the freedom-of-choice loophole. The researchers used distant quasars, one of which emitted its light 7.8 billion years ago and the other 12.2 billion years ago, to determine the measurements to be made on pairs of entangled photons. They found correlations among more than 30,000 pairs of photons, to a degree that far exceeded the limit that Bell originally calculated for a classically based mechanism.

"If some conspiracy is happening to simulate quantum mechanics by a mechanism that is actually classical, that mechanism would have had to begin its operations - somehow knowing exactly when, where, and how this experiment was going to be done - at least 7.8 billion years ago. That seems incredibly implausible, so we have very strong evidence that quantum mechanics is the right explanation," says co-author Alan Guth, the Victor F. Weisskopf Professor of Physics at MIT.

"The Earth is about 4.5 billion years old, so any alternative mechanism - different from quantum mechanics - that might have produced our results by exploiting this loophole would've had to be in place long before even there was a planet Earth, let alone an MIT," adds David Kaiser, the Germeshausen Professor of the History of Science and professor of physics at MIT. "So we've pushed any alternative explanations back to very early in cosmic history."

Guth and Kaiser's co-authors include Anton Zeilinger and members of his group at the Austrian Academy of Sciences and the University of Vienna, as well as physicists at Harvey Mudd College and the University of California at San Diego.

A decision, made billions of years ago

In 2014, Kaiser and two members of the current team, Jason Gallicchio and Andrew Friedman, proposed an experiment to produce entangled photons on Earth - a process that is fairly standard in studies of quantum mechanics. They planned to shoot each member of the entangled pair in opposite directions, toward light detectors that would also make a measurement of each photon using a polarizer.

Researchers would measure the polarization, or orientation, of each incoming photon's electric field, by setting the polarizer at various angles and observing whether the photons passed through - an outcome for each photon that researchers could compare to determine whether the particles showed the hallmark correlations predicted by quantum mechanics.

The team added a unique step to the proposed experiment, which was to use light from ancient, distant astronomical sources, such as stars and quasars, to determine the angle at which to set each respective polarizer. As each entangled photon was in flight, heading toward its detector at the speed of light, researchers would use a telescope located at each detector site to measure the wavelength of a quasar's incoming light.

If that light was redder than some reference wavelength, the polarizer would tilt at a certain angle to make a specific measurement of the incoming entangled photon - a measurement choice that was determined by the quasar. If the quasar's light was bluer than the reference wavelength, the polarizer would tilt at a different angle, performing a different measurement of the entangled photon.

In their previous experiment, the team used small backyard telescopes to measure the light from stars as close as 600 light years away. In their new study, the researchers used much larger, more powerful telescopes to catch the incoming light from even more ancient, distant astrophysical sources: quasars whose light has been traveling toward the Earth for at least 7.8 billion years - objects that are incredibly far away and yet are so luminous that their light can be observed from Earth.

Tricky timing

On Jan. 11, 2018, "the clock had just ticked past midnight local time," as Kaiser recalls, when about a dozen members of the team gathered on a mountaintop in the Canary Islands and began collecting data from two large, 4-meter-wide telescopes: the William Herschel Telescope and the Telescopio Nazionale Galileo, both situated on the same mountain and separated by about a kilometer.

One telescope focused on a particular quasar, while the other telescope looked at another quasar in a different patch of the night sky. Meanwhile, researchers at a station located between the two telescopes created pairs of entangled photons and beamed particles from each pair in opposite directions toward each telescope.

In the fraction of a second before each entangled photon reached its detector, the instrumentation determined whether a single photon arriving from the quasar was more red or blue, a measurement that then automatically adjusted the angle of a polarizer that ultimately received and detected the incoming entangled photon.

"The timing is very tricky," Kaiser says. "Everything has to happen within very tight windows, updating every microsecond or so."


Demystifying a mirage

The researchers ran their experiment twice, each for around 15 minutes and with two different pairs of quasars. For each run, they measured 17,663 and 12,420 pairs of entangled photons, respectively. Within hours of closing the telescope domes and looking through preliminary data, the team could tell there were strong correlations among the photon pairs, beyond the limit that Bell calculated, indicating that the photons were correlated in a quantum-mechanical manner.

Guth led a more detailed analysis to calculate the chance, however slight, that a classical mechanism might have produced the correlations the team observed.

He calculated that, for the best of the two runs, the probability that a mechanism based on classical physics could have achieved the observed correlation was about 10 to the minus 20 - that is, about one part in one hundred billion billion, "outrageously small," Guth says. For comparison, researchers have estimated the probability that the discovery of the Higgs boson was just a chance fluke to be about one in a billion.

"We certainly made it unbelievably implausible that a local realistic theory could be underlying the physics of the universe," Guth says.

And yet, there is still a small opening for the freedom-of-choice loophole. To limit it even further, the team is entertaining ideas of looking even further back in time, to use sources such as cosmic microwave background photons that were emitted as leftover radiation immediately following the Big Bang, though such experiments would present a host of new technical challenges.

"It is fun to think about new types of experiments we can design in the future, but for now, we are very pleased that we were able to address this particular loophole so dramatically. Our experiment with quasars puts extremely tight constraints on various alternatives to quantum mechanics. As strange as quantum mechanics may seem, it continues to match every experimental test we can devise," Kaiser says.

Friday, August 24, 2018

Chinese private space company to launch first carrier rocket

China will launch its first solid-propellant carrier rocket developed by a Chinese private company late this year. The ZQ-1 rocket was developed by Landspace, a Beijing-based rocket-maker. Its technicians are former state-owned aerospace industry workers. Carrying a small satellite, the rocket will be launched at the Jiuquan Satellite Launch Center in northwest China, the company said Thursday. "If the launch mission can go well, the ZQ-1 will become China's first private carrier rocket that can send satellites into space," said Zhang Changwu, CEO of Landspace. The 19-meter-long rocket has a 1.35-meter diameter, a takeoff weight of 27 tonnes and thrust of 45 tonnes. It is flexible, cost-efficient and has been designed with mature technology and fast response ability. "After nine months of development, the rocket completed the final assembly Monday and entered the launching phase, showing that the company is capable of making rockets," Zhang said. The satellite, Future, carried by the rocket is for space science and remote sensing for a TV show on China Central Television. It will orbit for two years. ZQ is short for Zhuque (Vermilion bird). It is one of the four spirits of ancient Chinese mythology, representing fire and controlling the southerly direction.


The company also plans to launch ZQ-2, a liquid-fueled rocket, in 2020.

China has more than 60 private companies entering the commercial space industry. They are growing fast and competing in market for launches of small satellites and rockets.

Thursday, August 23, 2018

Heat shield install brings Orion spacecraft closer to space

During Exploration Mission-1 (EM-1), an uncrewed Orion spacecraft will launch atop NASA's Space Launch System rocket and begin a three-week voyage in space, taking it about 40,000 miles beyond the Moon and back to Earth. On its return, the spacecraft's heat shield will need to withstand temperatures of nearing 5,000 degrees Fahrenheit during its fiery re-entry through the Earth's atmosphere before it splashes down in the Pacific Ocean. Technicians at NASA's Kennedy Space Center (KSC) in Florida recently secured the heat shield to the bottom of the crew module, using 68 bolts. Designed and manufactured by Orion prime contractor, Lockheed Martin, the heat shield is like an intricate puzzle with pieces that all have to fit together perfectly. Before the final installation, a fit check was performed to ensure all of the bolt fittings lined up. "Installation of the EM-1 crew module heat shield is a significant milestone representing the beginning of closing out the crew module assembly," said Jules Schneider, Lockheed Martin Orion senior manager for KSC Operations. "When the heat shield is installed, access to components becomes more difficult, and in some cases there is no more access. So by installing the heat shield you are declaring that a certain percentage of the spacecraft is finished."


Measuring 16.5 feet in diameter, Orion's new heat shield is the largest of its kind developed for missions that will carry astronauts. The heat shield base structure has a titanium truss covered with a composite substrate, or a skin composed of layers of carbon fiber material.

In a new process, several large blocks of an ablative material called Avcoat, licensed from Boston-based Textron Systems, were produced at Michoud Assembly Facility in New Orleans by Lockheed Martin. They were shipped to Kennedy, where Lockheed Martin technicians machined them into more than 180 unique blocks and bonded them to the heat shield's surface.

To fill tiny gaps between the blocks, the seams were filled with a mixture that over time will become solid. Technicians applied a coat of white epoxy paint to the heat shield's surface and then applied aluminized tape after the painted surface dried. The tape provides surface resistivity, and absorbs solar heat and infrared emissions.

"Witnessing assembly, test and installation of the EM-1 crew module heat shield brought an appreciation for its innovative design and assembly techniques," said Amy Marasia, the Crew Module Assembly operations lead in NASA's Orion Production Operations.

While Avcoat isn't new to spacecraft - it was used on the heat shields of Apollo and the Orion Exploration Flight Test-1 - the technique of using blocks instead of injecting the ablative material is proving to be a real production time-saver.

"A benefit of switching from the honeycomb system to the blocks is we now can make the Avcoat blocks at the same time that the Orion structure is being made, and when the module is ready we can secure the blocks, which saves time," said John Kowal, NASA Orion Thermal Protection System manager at Johnson Space Center in Houston.

"Before, with EFT-1, we had to wait for the carrier portion to be done, and then apply the Avcoat directly to the crew module."

During its first mission around the Moon, engineers will monitor how Orion's systems perform in the environment of deep space and its return to Earth. During re-entry the ablative material of the Avcoat blocks will burn away, essentially carrying the heat away from Orion because of the gases created during the ablative process.

Orion is the exploration spacecraft that will carry astronauts to deep-space destinations, including the Moon and on to Mars. Orion will be equipped with power, communications and life support systems to sustain space travelers during their long-duration missions and return them safely to Earth.

Wednesday, August 22, 2018

Scientists confirm ice exists at Moon's poles

Scientists said Tuesday they have confirmed the existence of ice on the Moon's surface for the first time, a discovery that could one day help humans survive there. Signs of ice on the Moon have been reported by scientists for years, but previous observations could have been explained by other phenomena, such as unusually reflective lunar soil, the study authors said. "This is the first time scientists have definitive evidence for the presence of water ice on the surface," lead author Shuai Li of the Hawaii Institute of Geophysics and Planetology told AFP. The ice mainly lies in the frigid shadows of craters at the lunar poles, and was detected using instruments that flew on the Chandrayaan-1 spacecraft, launched in 2008 by the Indian Space Research Organization. Using data from NASA's Moon Mineralogy Mapper (M3) instrument, researchers identified three chemical signatures "that definitively prove there is water ice at the surface of the Moon," said a NASA statement. The polar regions where the ice lies are "super cold," Li said, noting that the warmest temperatures never reach above minus 250 degrees Fahrenheit (-157 Celsius. It is unclear exactly how much ice exists on the surface, since the instruments could only detect ice within a few millimeters of the Moon's surface, he said.


But NASA said if there is enough of the ice, "water would possibly be accessible as a resource for future expeditions to explore and even stay on the Moon."

The US space agency is aiming to return humans to the Moon in the coming years for the first time since the storied Apollo missions of the 1960s and 1970s.

Li said the best way to find out more about the Moon's ice and how to tap into it as a resource would be to send a robotic rover to explore the lunar poles.

The full study was published in Monday's edition of the Proceedings of the National Academy of Sciences.

Tuesday, August 21, 2018

NASA's NICER Does the Space Station Twist

This time-lapse video, obtained June 8, 2018, shows the precise choreography of NASA's Neutron star Interior Composition Explorer (NICER) as it studies pulsars and other X-ray sources from its perch aboard the International Space Station. NICER observes and tracks numerous sources each day, ranging from the star closest to the Sun, Proxima Centauri, to X-ray sources in other galaxies. Movement in the movie, which represents a little more than one 90-minute orbit, is sped up by 100 times. One factor in NICER's gyrations is the motion of the space station's solar arrays, each of which extends 112 feet (34 meters). Long before the panels can encroach on NICER's field of view, the instrument pirouettes to aim its 56 X-ray telescopes at a new celestial target. As the movie opens, the station's solar arrays are parked to prepare for the arrival and docking of the Soyuz MS-09 flight, which launched on June 6 carrying three members of the Expedition 56 crew. Then the panels reorient themselves and begin their normal tracking of the Sun. Neutron stars, also called pulsars, are the crushed cores left behind when massive stars explode. They hold more mass than the Sun in a ball no bigger than a city. NICER aims to discover more about pulsars by obtaining precise measures of their size, which will determine their internal make-up.


An embedded technology demonstration, called Station Explorer for X-ray Timing and Navigation Technology (SEXTANT), is paving the way for using pulsars as beacons for a future GPS-like system to aid spacecraft navigation in the solar system - and beyond.

Sunday, August 19, 2018

Study of material surrounding distant stars shows Earth's ingredients 'pretty normal'

The Earth's building blocks seem to be built from 'pretty normal' ingredients, according to researchers working with the world's most powerful telescopes. Scientists have measured the compositions of 18 different planetary systems from up to 456 light years away and compared them to ours, and found that many elements are present in similar proportions to those found on Earth. This is amongst the largest examinations to measure the general composition of materials in other planetary systems, and begins to allow scientists to draw more general conclusions on how they are forged, and what this might mean for finding Earth-like bodies elsewhere. "Most of the building blocks we have looked at in other planetary systems have a composition broadly similar to that of the Earth", said researcher Dr Siyi Xu of the Gemini Observatory in Hawaii, who was presenting the work at the Goldschmidt conference in Boston. The first planets orbiting other stars were only found in 1992 (this was orbiting a pulsar), since then scientists have been trying to understand whether some of these stars and planets are similar to our own solar system. "It is difficult to examine these remote bodies directly. Because of the huge distances involved, their nearby star tends to drown out any electromagnetic signal, such as light or radio waves" said Siyi Xu. "So we needed to look at other methods".


Because of this, the team decided to look at how the planetary building blocks affect signals from white dwarf stars. These are stars which have burnt off most of their hydrogen and helium, and shrunk to be very small and dense - it is anticipated that our Sun will become a white dwarf in around 5 billion years.

Dr Xu continued, "White dwarfs' atmospheres are composed of either hydrogen or helium, which give out a pretty clear and clean spectroscopic signal. However, as the star cools, it begins to pull in material from the planets, asteroids, comets and so on which had been orbiting it, with some forming a dust disk, a little like the rings of Saturn.

"As this material approaches the star, it changes how we see the star. This change is measurable because it influences the star's spectroscopic signal, and allows us to identify the type and even the quantity of material surrounding the white dwarf. These measurements can be extremely sensitive, allowing bodies as small as an asteroid to be detected".

The team took measurements using spectrographs on the Keck telescope in Hawaii, the world's largest optical and infrared telescope, and on the Hubble Space Telescope.

Siyi Xu continued, "In this study, we have focused on the sample of white dwarfs with dust disks. We have been able to measure calcium, magnesium, and silicon content in most of these stars, and a few more elements in some stars. We may also have found water in one of the systems, but we have not yet quantified it: it's likely that there will be a lot of water in some of these worlds. For example, we've previously identified one star system, 170 light years away in the constellation Bootes, which was rich in carbon, nitrogen and water, giving a composition similar to that of Halley's Comet. In general though, their composition looks very similar to bulk Earth.

This would mean that the chemical elements, the building blocks of earth are common in other planetary systems. From what we can see, in terms of the presence and proportion of these elements, we're normal, pretty normal. And that means that we can probably expect to find Earth-like planets elsewhere in our Galaxy".

Dr Xu continued "This work is still on-going and the recent data release from the Gaia satellite, which so far has characterized 1.7 billion stars, has revolutionized the field. This means we will understand the white dwarfs a lot better. We hope to determine the chemical compositions of extrasolar planetary material to a much higher precision"

Professor Sara Seager, Professor of Planetary Science at Massachusetts Institute of Technology, is also the deputy science director of the recently-launched TESS (Transiting Exoplanet Survey Satellite) mission, which will search for exoplanets. She said:

"It's astonishing to me that the best way to study exoplanet interiors is by planets ripped apart and absorbed by their white dwarf host star. It is great to see progress in this research area and to have solid evidence that planets with Earth-like compositions are common--fueling our confidence that an Earth-like planet around a very nearby normal star is out there waiting to be found".

Friday, August 17, 2018

China unveils Chang'e-4 rover to explore Moon's far side

China's moon lander and rover for the Chang'e-4 lunar probe, which is expected to land on the far side of the moon this year, was unveiled Wednesday. Images displayed at Wednesday's press conference showed the rover was a rectangular box with two foldable solar panels and six wheels. It is 1.5 meters long, 1 meter wide and 1.1 meters high.Wu Weiren, the chief designer of China's lunar probe program, said the Chang'e-4 rover largely kept the shape and conditions of its predecessor, Yutu (Jade Rabbit), China's first lunar rover for the Chang'e-3 lunar probe in 2013. However, it also has adaptable parts and an adjustable payload configuration to deal with the complex terrain on the far side of the moon, the demand of relay communication, and the actual needs of the scientific objectives, according to space scientists. Like Yutu, the rover will be equipped with four scientific payloads, including a panoramic camera, infrared imaging spectrometer and radar measurement devices, to obtain images of moon's surface and detect lunar soil and structure. It will also endure vacuum, intense radiation and extremes of temperature. The moon has a large temperature difference between day and night, which can reach more than 300 degrees Celsius.


Both the lander and rover will carry international payloads for other countries.

The Chang'e-4 lunar probe will land on the Aitken Basin of the lunar south pole region on the far side of the moon, which is a hot spot for scientific and space exploration.

Direct communication with the far side of the moon, however, is not possible, which is one of the many challenges for the Chang'e-4 lunar probe mission.

China launched a relay satellite, named Queqiao, in May, to set up a communication link between the Earth and Chang'e-4 lunar probe.

The global public will have a chance to name the rover, according to State Administration of Science, Technology and Industry for National Defense.

Participants can submit their proposed names for the rover through the internet from Aug. 15 to Sept. 5, and the official name will be announced in October after several selection rounds.

Winners will be rewarded at most 3,000 yuan and invited to watch the lunar probe launch.

The name Yutu was chosen from 200,000 proposals submitted over two months worldwide.

Thursday, August 16, 2018

Impact of a stellar intruder on our solar system

The solar system was formed from a protoplanetary disk consisting of gas and dust. Since the cumulative mass of all objects beyond Neptune is much smaller than expected and the bodies there have mostly inclined, eccentric orbits it is likely that some process restructured the outer solar system after its formation. Susanne Pfalzner from the Max Planck Institute for Radio Astronomy in Bonn, Germany, and her colleagues present a study showing that a close fly-by of a neighbouring star can simultaneously lead to the observed lower mass density in the outer part of the solar system and excite the bodies there onto eccentric, inclined orbits. Their numerical simulations show that many additional bodies at high inclinations still await discovery, perhaps including a sometimes postulated Planet X. The findings are published in the present issue of "The Astrophysical Journal." A near catastrophe billions of years ago might have shaped the outer parts of the solar system, while leaving the inner regions basically untouched. Researchers from the Max Planck Institute for Radio Astronomy in Bonn and their collaborators found that a close fly-by of another star can explain many of the features observed in the outer solar system.


"Our group has been looking for years at what fly-bys can do to other planetary systems never considering that we actually might live right in such a system," says Susanne Pfalzner, the leading author of the project. "The beauty of this model lies in its simplicity."

The basic scenario of the formation of the solar system has long been known: our Sun was born from a collapsing cloud of gas and dust. In the process a flat disk was formed where not only large planets grew but also smaller objects like the asteroids, dwarf planets, etc. Due to the flatness of the disk one would expect that the planets orbit in a single plane unless something dramatic happened afterwards.

Looking at the solar system right to the orbit of Neptune everything seems fine: most planets move on fairly circular orbits and their orbital inclinations vary only slightly. However, beyond Neptune things become very messy. The biggest puzzle is the dwarf planet Sedna, which moves on an inclined, highly eccentric orbit and is so far outside, that it could not have been scattered by the planets there.

Just outside Neptune's orbit another strange thing happens. The cumulative mass of all the objects dramatically drops by almost three orders of magnitude. This happens at approximately the same distance where everything becomes messy. It might be coincidental, but such coincidences are rare in nature.

Susanne Pfalzner and her co-workers suggest that a star was approaching the Sun at an early stage, 'stealing' most of the outer material from the Sun's protoplanetary disk and throwing what was left over into inclined and eccentric orbits.

Performing thousands of computer simulations they checked what would happen when a star passes very close-by and perturbs the once larger disk. It turned out that the best fit for today's outer solar systems comes from a perturbing star which had the same mass as the Sun or somewhat lighter (0.5-1 solar mass) and flew past at approximately three times the distance of Neptune.

However, the most surprising thing for the researchers was that a fly-by does not only explain the strange orbits of the objects of the outer solar system, but also gives a natural explanation for several unexplained features of our solar system, including the mass ratio between Neptune and Uranus, and the existence of two distinct populations of Kuiper Belt objects.

"It is important to keep exploring all the possible avenues for explaining the structure of the outer solar system. The data are increasing but still too sparse, so theories have a lot of wiggle room to develop," says Pedro Lacerda from the Queen's University in Belfast, a co-author of the paper. "There is a certain danger that one theory crystallises as truth, not because it explains the data better but because of other pressures. Our paper shows that a lot of what we currently know can be explained by something as simple as a stellar fly-by."

The big question is the likelihood for such an event. Nowadays, fly-bys even hundreds of times more distant are luckily rare. However, stars like our Sun are typically born in large groups of stars which are much more densely packed. Therefore, close fly-bys were significantly more common in the distant past. Performing another type of simulation, the team found that there was a 20%-30% chance of experiencing a fly-by over the first billion years of the Sun's life.

This is no final proof that a stellar fly-by caused the messy features of the outer solar system, but it can reproduce many observational facts and seems relatively realistic. So far it is the simplest explanation and if simplicity is a sign for validity this model is the best candidate so far.

"In summary, our close fly-by scenario offers a realistic alternative to present models suggested to explain the unexpected features of the outer solar system," concludes Susanne Pfalzner. "It should be considered as an option for shaping the outer solar system. The strength of the fly-by hypothesis lies in the explanation of several outer solar system features by one single mechanism."

Wednesday, August 15, 2018

Iron and Titanium in the Atmosphere of an Exoplanet

Exoplanets, planets in other solar systems, can orbit very close to their host star. When, in addition to this, the host star is much hotter than our Sun, then the exoplanet becomes as hot as a star. The hottest "ultra-hot" planet was discovered last year by American astronomers. Today, an international team, led by researchers from the University of Geneva (UNIGE), who joined forces with theoreticians from the University of Bern (UNIBE), Switzerland, discovered the presence of iron and titanium vapours in the atmosphere of this planet. The detection of these heavy metals was made possible by the surface temperature of this planet, which reaches more than 4,000 degrees [Celsius]. This discovery is published in the journal Nature [www.nature.com]. KELT-9 is a star located 650 light-years from Earth in the constellation Cygnus (the Swan). With a temperature of over 10,000 degrees [Celsius], it is almost twice as hot as the Sun. This star is orbited by a giant gas planet, KELT-9b, which is 30 times closer than the Earth's distance from the Sun. Because of this proximity, the planet circles its star in 36 hours and is heated to a temperature of over 4,000 degrees. It's not as hot as the Sun, but hotter than many stars. At present, we do not yet know what an atmosphere looks like and how it can evolve under such conditions.


That is why NCCR PlanetS researchers affiliated with the University of Bern recently performed a theoretical study on the atmosphere of the planet KELT-9b.

"The results of these simulations show that most of the molecules found there should be in atomic form, because the bonds that hold them together are broken by collisions between particles that occur at these extremely high temperatures," explains Kevin Heng, professor at the UNIBE. This is a direct consequence of the extreme temperature. Their study also predicts that it should be possible to observe gaseous atomic iron, in the planet's atmosphere using current telescopes.


Light Reveals the Chemical Components of the Atmosphere
The UNIGE FOUR ACES team, which is also part of the NCCR PlanetS at the Department of Astronomy of the Faculty of Science of the UNIGE, had observed this planet precisely as it was moving in front of its host star (i.e., during a transit). During transit, a tiny fraction of the light from the star filters through the planet's atmosphere, and analysis of this filtered light can reveal the chemical composition of the atmosphere.

This is achieved with a spectrograph, an instrument that spreads white light into its component colours, called a spectrum. If present among the components of the atmosphere, iron vapour would leave a well-recognisable fingerprint in the spectrum of the planet.

Using the HARPS-North spectrograph, built in Geneva and installed on the Telescopio Nazionale Galileo in La Palma, astronomers discovered a strong signal corresponding to iron vapour in the planet's spectrum. "With the theoretical predictions in hand, it was like following a treasure map," says Jens Hoeijmakers, a researcher at the Universities of Geneva and Bern and lead author of the study, "and when we dug deeper into the data, we found even more," he adds with a smile. Indeed, the team also detected the signature of another metal in vapour form: titanium.

This discovery reveals the atmospheric properties of a new class of so-called "ultra-hot Jupiter." However, scientists believe that many exoplanets have completely evaporated in environments similar to KELT-9b. Although this planet is probably massive enough to withstand total evaporation, this new study demonstrates the strong impact of stellar radiation on the composition of the atmosphere. Indeed, these observations confirm that the high temperatures reigning on this planet break apart most molecules, including those containing iron or titanium.

In cooler giant exoplanets, these atomic species are thought to be hidden within gaseous oxides or in the form of dust particles, making them hard to detect. This is not the case on KELT-9b. "This planet is a unique laboratory to analyze how atmospheres can evolve under intense stellar radiation," concludes David Ehrenreich, principal investigator with the UNIGE's FOUR ACES team.

Tuesday, August 14, 2018

India's Second Moon Mission as "Complex" as NASA's Apollo Mission

The Indian Space Agency had planned the launch of its second moon mission for October this year, but scientists reviewing their preparedness suggested that more tests were needed before the launch. The mission is now likely to be preceded by Israel's moon mission, planned for December this year. The Indian Space Research Organisation (ISRO) has announced the postponement of its much-awaited second lunar mission - Chandrayaan 2. The mission was expected to be launched in October this year but ISRO says it will now conduct it in the first quarter of 2019. "We are aiming to launch the mission on January 3 next year, but the window to land on the lunar surface is open until March 2019. Chandrayaan-2 mission is the most complex mission attempted by ISRO so far. The mission has three components - orbiter, lander, and rover. We set up a committee of eminent scientists from across the country which studied the project and suggested changes. It is nothing less than the Apollo mission," ISRO Chairman K. Sivan told reporters in Bengaluru. Apollo was the NASA program that resulted in American astronauts' making a total of 11 spaceflights and walking on the moon. The first moon landing took place in 1969. The last moon landing was in 1972.


ISRO has increased the weight of Chandrayaan-2 by 600 kg as the space scientists had noticed during experiments that after the moon lander was ejected, the satellite would shake. So they decided that design modification was required for landing and the mass had to be increased.

The total estimated cost of the mission is about INR 8 billion ($124 million), which includes INR 2 billion ($31 million) at the cost of launching and INR 6 billion ($93 million) for the satellite.

ISRO has pointed out that the success rate of lunar landing missions is less than 50% as 27 had failed out of 47 lunar landings.

Saturday, August 11, 2018

NASA postpones for 24 hours launch of historic spaceship to Sun

NASA postponed until Sunday the launch of the first ever spacecraft to fly directly toward the Sun on a mission to plunge into our star's sizzling atmosphere and unlock its mysteries. The reason for the delay was not immediately clear, but was called for after a gaseous helium alarm was sounded in the last moments before liftoff, officials said. Engineers are taking utmost caution with the $1.5 billion Parker Solar Probe, which Thomas Zurbuchen, head of NASA's science mission directorate, described as one of the agency's most "strategically important missions." The next launch window opens at 3:31 am (0731 GMT) on Sunday, when weather conditions are 60 percent favorable for launch, NASA said. By coming closer to the Sun than any spacecraft in history, the unmanned probe's main goal is to unveil the secrets of the corona, the unusual atmosphere around the Sun. Not only is the corona about 300 times hotter than the Sun's surface, but it also hurls powerful plasma and energetic particles that can unleash geomagnetic space storms, wreaking havoc on Earth by disrupting the power grid. These solar outbursts are poorly understood, but pack the potential to wipe out power to millions of people.


- 'Full of mysteries' -

The probe is protected by an ultra-powerful heat shield that is 4.5 inches (11.43 centimeters) thick.

The shield should enable the spacecraft to survive its close shave with the fiery star, coming within 3.83 million miles (6.16 million kilometers) of the Sun's surface.

The heat shield is built to withstand radiation equivalent to up to about 500 times the Sun's radiation on Earth.

Even in a region where temperatures can reach more than a million degrees Fahrenheit, the sunlight is expected to heat the shield to just around 2,500 degrees Fahrenheit (1,371 degrees Celsius).

If all works as planned, the inside of the spacecraft should stay at just 85 degrees Fahrenheit.

"The sun is full of mysteries," said Nicky Fox, project scientist at the Johns Hopkins University Applied Physics Lab.

- 91-year-old namesake -

The tools on board will measure the expanding corona and continually flowing atmosphere known as the solar wind, which solar physicist Eugene Parker first described in 1958.

Parker, now 91, recalled that at first some people did not believe in his theory.

But then, the launch of NASA's Mariner 2 spacecraft in 1962 -- becoming the first robotic spacecraft to make a successful planetary encounter -- proved them wrong.

"It was just a matter of sitting out the deniers for four years until the Venus Mariner 2 spacecraft showed that, by golly, there was a solar wind," Parker said earlier this week.

Parker said he was "impressed" by the Parker Solar Probe, calling it "a very complex machine."

According to Zurbuchen, Parker is an "incredible hero of our scientific community."

"Life is all about these big arcs. Sometimes you just see, like how over a lifetime, things just come together and create these amazing stories, these leaps going forward."

Friday, August 10, 2018

Satellite measurements of the Earth's magnetosphere promise better space weather forecasts

Earth is constantly being hammered by charged particles emitted by the Sun that have enough power to make life on Earth almost impossible. We survive because Earth's magnetic field traps and deflects these particles, preventing the vast majority of them from ever reaching the planet's surface. The trapped particles bounce back and forth between the North and South poles in complex, ever-changing patterns that are also influenced by equally intricate and shifting electric fields. We get to enjoy the sight of those particles when the bands they move in (the Van Allen radiation belts) dip into our atmosphere near the poles creating the Northern (and Southern) lights. However, bursts of these particles can damage satellites and sensitive equipment on the ground. It is therefore vital to understand the intricacies of the radiation belts. So far, NASA have launched twin satellites to study the Van Allen belts--however, their orbits only allow them to explore the equatorial regions. This limits our ability to understand flow of particles and prevents us from predicting their effects on all satellites. To also explore regions further from the equator, the Institute of Space and Astronautical Science, a division of the Japan Aerospace Exploration Agency, launched the Arase satellite in 2016.


A Japan-based research team centered at Kanazawa University equipped the Arase satellite with multiple different sensors (termed the Plasma Wave Experiment) to probe the electric field and plasma waves in the Earth's inner magnetosphere. Now, they have collected their first set of data from their sensors, which they recently published in the Springer journal Earth, Planets and Space.

The Arase consists primarily of electric and magnetic field detectors covering a wide frequency range; it can also measure plasma/particles in a wide energy range. To improve efficiency, an on-board computer studies the correlations between the fields and the particles before sending only the most important information back to Earth.

"The Plasma Wave Experiment equipment has passed initial checks and has successfully acquired high quality data. Huge amount of burst waveform data has been taken, and we should soon know a lot more about mechanisms of wave-particle interaction occurring in the inner magnetosphere than before.

Another strength of our project is that we can also compare the satellite data with data collected simultaneously on the ground. We expect those comparisons will greatly broaden our understanding of this area of science," first author Yoshiya Kasahara says.

Understanding how electrons and other particles are hurled out of the magnetosphere onto our planet could be key to predicting such bursts and protecting against them.

Thursday, August 9, 2018

Arianespace to launch Spire small satellites on Vega SSMS POC flight

The multi-launch contract with Spire - a company providing weather, maritime, and aviation data to public and private customers - will cover a significant number of CubeSats to be launched on Vega as part of the Small Spacecraft Mission Service Proof Of Concept (POC) flight in 2019, as well as options on subsequent Vega flights. With more than 80 satellites placed in orbit during the past four years, Spire has quickly become an important leader in the New Space community. Built in-house by Spire using its LEMUR2 CubeSat platform, the nanosatellites will weigh approximately 5 kg. at launch and are designed to have a nominal service life of two to three years once positioned in a Sun-synchronous orbit at 500 km. Each satellite carries multiple sensors, making them capable of performing data collection for all of Spire's data products. The Vega Proof of Concept (POC) flight is the first of the Small Spacecraft Mission Service (SSMS) - a program initiated by the European Space Agency in 2016, with the contribution of the European Commission. For all the European partners involved, its purpose is to perfectly address the promising microsatellite market for both institutional and commercial needs with a new rideshare concept on the Vega light-lift launcher.


Vega is part of the Arianespace launcher family, alongside the heavy-lift Ariane 5 and the medium-lift Soyuz, all of which are operated from the Guiana Space Center in French Guiana. Avio, based in Colleferro Italy, is Vega's industrial prime contractor.

Following the signature of this contract, which is the launch services company's first with Spire, Arianespace CEO Stephane Israel said: "We are thrilled to have Spire on board the POC flight of Vega's Small Spacecraft Mission Service dispenser, which shows Arianespace's continuous commitment to increased access to space for the growing small satellite market. The Vega launch vehicle offers a flexible solution for this burgeoning segment of the industry."

Wednesday, August 8, 2018

New launch unit standards announced for smallsats

The Aerospace Corporation (Aerospace) announced details of a new small satellite (smallsat) standard called a Launch Unit (Launch-U) during a briefing at the Small Satellite Conference in Logan, Utah. This standard provides major benefits to the smallsat industry-manufacturers, launch providers, and satellite users-by increasing access to space and decreasing launch costs. It also enables the space community to come together to work innovative solutions for sharing costs, adopting new business models, and adapting to regulatory or statutory changes. "We are proud to partner with industry, government, and academia to develop the first official Launch Unit standard," said Steve Isakowitz, Aerospace president and CEO. "The Launch-U team's efforts will help reduce the complexities on the satellite and launch vehicle sides. It will also lead to shorter integration timelines and increased access to space." The space community was in search of a standard to make launching small satellites more flexible. Given Aerospace's role as an objective technical advisor, the community identified the corporation as the ideal partner to work across all elements of the space enterprise, from satellite and launch manufacturers to service providers and government officials.


"The Launch-U concept was born out of the industry's continuous requests for help, said Dr. Randy Villahermosa, general manager of Aerospace's Innovation Initiatives. "The goal was to create a standard that industry would view as enabling rather than an impediment to growth. Aerospace was a key broker in making this a reality."

Carrie O'Quinn, senior project engineer for Aerospace's Research and Development Department and the Launch-U lead, emphasized that currently there are no industry standards for satellites between the size of a CubeSat (approximately the size of a toaster) and an EELV Secondary Payload Adapter (ESPA) class satellite, which is about the size of a large dorm refrigerator.

"The Launch-U standard seeks to change this through our volume recommendation of 45 cm x 45 cm x 60 cm, said O'Quinn. "That's roughly the size of two carry-on bags strapped together. We also address a mass range, fundamental frequency, and loads in the recommendations."

The space access industry is altering in an exceedingly rapid pace and is driven by smallsat and small launch vehicle development, the increasing popularity of multi-manifest missions, and a widespread interest in reducing launch cost and timelines while deploying even more spacecraft. Currently, industry experts estimate that 6,000 to 20,000 smallsats could be launched over the next 10 years.

O'Quinn explained that the group's vision for the Launch-U standard is the solution the industry is looking for. "This is not envisioned to be a requirement levied on spacecraft developers, but rather a standard that is embraced by all as a game-changer."

For industry, the next step is to develop hardware and other technical solutions needed to support the Launch-U. O'Quinn emphasized that each stakeholder plays a specific role in implementing the Launch-U.

"Launch vehicle providers, integrators, and aggregators can begin considering how Launch-U satellites will affect their business models once implemented," said O'Quinn. "For example, these companies might publish information on Launch-U launch costs, as Spaceflight Industries and other commercial entities currently do for CubeSat launch costs."

Satellite manufacturers could also build to the Launch-U standard and make it available to the community at large.

Monday, August 6, 2018

7,000 small satellites to be launched over coming decade

According to Euroconsult's latest report, Prospects for the Small Satellite Market, a significant expansion is underway in the smallsat market, both in terms of demand and systems' capabilities. About 7,000 smallsats are due to be launched over the next ten years, i.e. a six-fold increase from the 1,200 units launched over the past decade. About 50 constellations, two of which are mega constellations, account for over 80% of the smallsat count. "By 2022, an average of 580 smallsats will be launched every year as a result of initial constellation deployment. This compares to an annual average of 190 satellites launched over the past five years. The average will then jump to 850 satellites per year on subsequent years up to 2027 because of the deployment of one mega constellation," said Maxime Puteaux, Senior Consultant at Euroconsult and editor of the report. "Smallsat demand for constellations is cyclical as it is driven by deployment in batches whereas demand for single satellite missions is more stable. Performance improvements and continuous miniaturization reshape the smallsat market as customers have the choice between lighter satellites with the same capabilities or larger but more capable satellites. In the heaviest mass category, smallsats are now able to perform missions that were only achievable in the past by satellites heavier that 500 kg."


Smallsat applications are multiple. In the past, "technology development" was the dominant application to test future technologies and payloads or for educational purposes. In future years, three applications will dominate the smallsat market:

Broadband Communication is by far the largest application with close to 3,500 satellites expected from 2018 to 2027 (of which 92% for two mega constellations);

Earth Observation will almost triple, from 540 satellites in the past to 1,400 anticipated from 2018 to 2027. Three constellations alone plan to launch more than 800 satellites during this period, of which two are cubesat-based;

Information for data collection and narrowband communications for AIS, ADS-B, Internet of Things, and Machine to Machine communication. It is a growing market with 850 satellites to be launched by 14 constellations that are currently raising funds or launching demonstrators.

The 7,000 smallsats that are due to be launched over 2018-2027 are valued at $38 billion for satellite manufacturing and launch, almost a quintupling decade-to-decade. The smaller growth in market value relative to that in smallsats count reflects the growing penetration of low-cost smallsats for 1) cubesats and nanosats below 50 kg of launch mass and 2) for large scale constellations with satellite unit cost of $1-$1.5 million.

Cubesats alone represent a mere 4% of future total market value. A significant part of that market is already contracted or captive via domestic providers as vertical integration (i.e. in-house manufacturing and/or launch) is more common for smallsats than for larger satellites.

The launch services of smallsats are expected to generate $16 billion in the next ten years i.e. strong growth over that of the past decade. Growth in launch revenues is stronger than that of satellite manufacturing with more diversity in launch services and various quality of services.

Smallsat operators currently launch with medium to heavy launchers that are contracted directly or through launch brokers. Several dedicated smallsat launchers are in development, the most advanced being on the edge to perform maiden flights, in order to be more responsive to market needs (on time, on orbit) but at the expense of a premium in specific price (price per kg into orbit).

Ready for Its Day in the Sun: The SWEAP Investigation

When NASA's Parker Solar Probe launches into space from the Kennedy Space Center, it will begin its journey to the Sun, our nearest star. The Parker Solar Probe will travel almost 90 million miles and eventually enter through the Sun's outer atmosphere to encounter a dangerous environment of intense heat and solar radiation. During this harrowing journey, it will fly closer to the Sun than any other human-made object. To revolutionize our understanding of our most important and life-sustaining star, scientists and engineers have built a suite of instruments aboard the Parker Solar Probe to conduct different experiments. Some of these instruments will be protected by a thick carbon-composite heat shield. However, others will be more exposed. The Solar Wind Electrons Alphas and Protons (SWEAP) investigation is the set of instruments that will directly measure the hot ionized gas in the solar atmosphere during the solar encounters. A key instrument on SWEAP called the Solar Probe Cup (SPC) was built at the Smithsonian Astrophysical Observatory (SAO) in Cambridge, Mass. The SPC is a small metal device that will peer around the protective heat shield of the spacecraft directly at the Sun. It will face some of the most extreme conditions ever encountered by a scientific instrument, and allow a sample of the Sun's atmosphere to be swept up for the first time.


The SPC uses high voltages to determine what type of particles can enter, which is a way of measuring the energy of the particle. This is crucial information for probing the wind of hot ionized gas that is constantly produced by the Sun. As the spacecraft flies towards the Sun for an encounter, the wind is directed straight into the cup.

Without the SPC, Parker Solar Probe would miss most of what is in between Earth and the Sun. This unique probe of the solar wind is important for scientists to better understand space weather, which is responsible for effects that range from endangering astronauts on space walks to impacting the electronics in communications satellites.

The Parker Solar Probe spacecraft, about the size of a small car, will travel towards the Sun's atmosphere at speeds of about 430,000 mph (700,000 km/hr), becoming the fastest human-made object.

Eventually, Parker Solar Probe will enter an orbit that approaches to within only 4 million miles from the star's surface. (For context, the Earth averages a distance of about 93 million miles from the Sun during its elliptical orbit.

Or, to put it another way, the spacecraft will travel about 96% of the way from the Earth to the Sun.) Parker Solar Probe, which will be carried into space by a Delta-IV Heavy rocket, is currently scheduled to launch on August 11, 2018.

The SWEAP Team is led by Justin Kasper currently at the University of Michigan (and currently an SAO Research Associate). On the SWEAP Investigation, SAO partners with team members from University of California, Berkeley, Space Sciences Laboratory, the NASA Marshall Space Flight Center, the University of Alabama, Huntsville, NASA Goddard Space Flight Center, Los Alamos National Laboratory, and the Massachusetts Institute of Technology. SAO built the SPC (Instrument Scientist: Tony Case), leads the Science Operations

Sunday, August 5, 2018

Russia Plans to Send Capsule With Microorganisms to Mars

Russian scientists plan to send a capsule containing microorganisms to Mars' natural satellite Phobos and then get it back to Earth in order to study the possible mutations during the space flight, Natalya Novikova, the head of the microbiology laboratory at the Institute of Biomedical Problems of the Russian Academy of Sciences, told Sputnik. The project will be carried out as part of the Bumerang mission, which reproduces Russia's attempted Fobos-Grunt mission. "Now as part of the Bumerang project - a repetition of the Fobos-Grunt mission - it is planned to do a new experiment with sending to Mars and returning back a capsule with microorganisms," Novikova said. In November 2011, Russia attempted to launch Fobos-Grunt mission to Mars, however, after moving into the orbit the spacecraft did not manage to start its engines.


Two months later, it reentered Earth's atmosphere and fell into the Pacific Ocean. The Fobos-Grunt project also provided for sending a capsule with microorganisms to Mars, with the experiment dubbed Biofobos.

Saturday, August 4, 2018

Astronomers Uncover New Clues to the Star That Wouldn't Die

What happens when a star behaves like it exploded, but it's still there? About 170 years ago, astronomers witnessed a major outburst by Eta Carinae, one of the brightest known stars in the Milky Way galaxy. The blast unleashed almost as much energy as a standard supernova explosion. Yet Eta Carinae survived. An explanation for the eruption has eluded astrophysicists. They can't take a time machine back to the mid-1800s to observe the outburst with modern technology. However, astronomers can use nature's own "time machine," courtesy of the fact that light travels at a finite speed through space. Rather than heading straight toward Earth, some of the light from the outburst rebounded or "echoed" off of interstellar dust, and is just now arriving at Earth. This effect is called a light echo. The light is behaving like a postcard that got lost in the mail and is only arriving 170 years later. By performing modern astronomical forensics of the delayed light with ground-based telescopes, astronomers uncovered a surprise. The new measurements of the 19th-century eruption reveal material expanding with record-breaking speeds up to 20 times faster than astronomers expected. The observed velocities are more like the fastest material ejected by the blast wave in a supernova explosion, rather than the relatively slow and gentle winds expected from massive stars before they die.


Based on this data, researchers suggest that the 1840s eruption may have been triggered by a prolonged stellar brawl among three rowdy sibling stars, which destroyed one star and left the other two in a binary system. This tussle may have culminated with a violent explosion when Eta Carinae devoured one of its two companions, rocketing more than 10 times the mass of our Sun into space. The ejected mass created gigantic bipolar lobes resembling the dumbbell shape seen in present-day images.

The results are reported in a pair of papers by a team led by Nathan Smith of the University of Arizona in Tucson, Arizona, and Armin Rest of the Space Telescope Science Institute in Baltimore, Maryland.

The light echoes were detected in visible-light images obtained since 2003 with moderate-sized telescopes at the Cerro Tololo Inter-American Observatory in Chile. Using larger telescopes at the Magellan Observatory and the Gemini South Observatory, both also located in Chile, the team then used spectroscopy to dissect the light, allowing them to measure the ejecta's expansion speeds. They clocked material zipping along at more than 20 million miles per hour (fast enough to travel from Earth to Pluto in a few days).

The observations offer new clues to the mystery surrounding the titanic convulsion that, at the time, made Eta Carinae the second-brightest nighttime star seen in the sky from Earth between 1837 and 1858. The data hint at how it may have come to be the most luminous and massive star in the Milky Way galaxy.

"We see these really high velocities in a star that seems to have had a powerful explosion, but somehow the star survived," Smith explained. "The easiest way to do this is with a shock wave that exits the star and accelerates material to very high speeds."

Massive stars normally meet their final demise in shock-driven events when their cores collapse to make a neutron star or black hole. Astronomers see this phenomenon in supernova explosions where the star is obliterated. So how do you have a star explode with a shock-driven event, but it isn't enough to completely blow itself apart? Some violent event must have dumped just the right amount of energy onto the star, causing it to eject its outer layers. But the energy wasn't enough to completely annihilate the star.

One possibility for just such an event is a merger between two stars, but it has been hard to find a scenario that could work and match all the data on Eta Carinae.

The researchers suggest that the most straightforward way to explain a wide range of observed facts surrounding the eruption is with an interaction of three stars, where the objects exchange mass.

If that's the case, then the present-day remnant binary system must have started out as a triple system. "The reason why we suggest that members of a crazy triple system interact with each other is because this is the best explanation for how the present-day companion quickly lost its outer layers before its more massive sibling," Smith said.

In the team's proposed scenario, two hefty stars are orbiting closely and a third companion is orbiting farther away. When the most massive of the close binary stars nears the end of its life, it begins to expand and dumps most of its material onto its slightly smaller sibling.

The sibling has now bulked up to about 100 times the mass of our Sun and is extremely bright. The donor star, now only about 30 solar masses, has been stripped of its hydrogen layers, exposing its hot helium core.

Hot helium core stars are known to represent an advanced stage of evolution in the lives of massive stars. "From stellar evolution, there's a pretty firm understanding that more massive stars live their lives more quickly and less massive stars have longer lifetimes," Rest explained. "So the hot companion star seems to be further along in its evolution, even though it is now a much less massive star than the one it is orbiting. That doesn't make sense without a transfer of mass."

The mass transfer alters the gravitational balance of the system, and the helium-core star moves farther away from its monster sibling. The star travels so far away that it gravitationally interacts with the outermost third star, kicking it inward. After making a few close passes, the star merges with its heavyweight partner, producing an outflow of material.

In the merger's initial stages, the ejecta is dense and expanding relatively slowly as the two stars spiral closer and closer. Later, an explosive event occurs when the two inner stars finally join together, blasting off material moving 100 times faster. This material eventually catches up with the slow ejecta and rams into it like a snowplow, heating the material and making it glow. This glowing material is the light source of the main historical eruption seen by astronomers a century and a half ago.

Meanwhile, the smaller helium-core star settles into an elliptical orbit, passing through the giant star's outer layers every 5.5 years. This interaction generates X-ray emitting shock waves.

A better understanding of the physics of Eta Carinae's eruption may help to shed light on the complicated interactions of binary and multiple stars, which are critical for understanding the evolution and death of massive stars.

The Eta Carinae system resides 7,500 light-years away inside the Carina nebula, a vast star-forming region seen in the southern sky.

Friday, August 3, 2018

Flight Tests to Prove Commercial Systems Fit for Human Spaceflight

The first test flights for new spacecraft designed by commercial companies in collaboration with NASA to carry astronauts to and from the International Space Station from the United States are known as Demo-1 for SpaceX and Orbital Flight Test for Boeing. NASA's goal in collaborating with Boeing and SpaceX is to achieve safe, reliable and cost-effective transportation to and from station on the companies' spacecraft. Both companies have matured their designs, are making significant progress through their extensive testing campaigns, and are headed toward flight tests to validate their systems. An uncrewed flight test was not a NASA requirement for certifying these systems for human spaceflight. Boeing and SpaceX volunteered to perform these tests to demonstrate their systems are safe for crew. "This was above and beyond the NASA requirement in the contract," said Kathy Lueders, Commercial Crew Program manager at NASA Kennedy. "Both partners said they really wanted to have an uncrewed flight test to make sure the integrated rockets, spacecraft and re-entry systems are all working as designed to be able to ensure the integrated system is functioning." Each test flight will provide data on the performance of the rockets, spacecraft, ground systems, and operations to ensure the systems are safe to fly astronauts. Boeing's CST-100 Starliner spacecraft will be launched atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida.


"Tomorrow we will meet the astronauts who will be the first to fly the CST-100 Starliner. Our commitment has always been to provide NASA and those crews the highest level of mission assurance," said John Mulholland, vice president and program manager for Boeing's Commercial Crew effort.

"We believe the earliest time we can confidently do that will be in mid-2019 after flying an uncrewed flight test late this year or early next year. I'm incredibly proud of the progress our team has made, and it has been inspiring to watch them work through challenges quickly, while developing a brand new human-rated spacecraft that Boeing, NASA and the nation can be proud of."

SpaceX designed its Crew Dragon spacecraft to launch atop the company's Falcon 9 rocket from historic Launch Complex 39A at NASA's Kennedy Space Center in Florida.

"Safely and reliably flying commercial crew missions for NASA remains the highest priority for SpaceX," said Benji Reed, Director of Crew Mission Management at SpaceX.

"We look forward to launching Crew Dragon-designed to be one of the safest, most-advanced human spaceflight systems ever built-and returning human-spaceflight capabilities to the United States for the first time since the Space Shuttle Program retired in 2011. SpaceX is targeting November 2018 for Crew Dragon's first demonstration mission and April 2019 for Crew Dragon's second demonstration mission, which will carry two NASA astronauts to and from the International Space Station."

NASA is making crew assignments now for the Boeing Crew Flight Test and SpaceX Demo-2 to support flight training as we return to launching our astronauts from American soil. As a partner approaches its target readiness date, NASA will work with the company and the Eastern Range to identify launch dates within the busy International Space Station schedule to ensure science investigations, as well as logistics activities and critical operations continue while these new spacecraft are tested.

Many of the team members leading the unique public-private partnership believe the agency is on the cusp of something life changing with its Commercial Crew Program.

"I'm excited to be part of the future of space travel," said Jon Cowart, acting deputy manager for the Commercial Crew Program's Mission Management and Integration office at NASA's Kennedy Space Center in Florida. "When we get to this point the companies will have tested every piece of the spacecraft individually, but there is so much more learning that occurs when the spacecraft is actually operated in space. The systems will be operated in the actual environment to test it and ensure it's ready for crew."

The hardware for these uncrewed missions is being prepared for launch. Boeing's Starliner spacecraft is being outfitted at the Commercial Crew and Cargo Processing Facility on the Kennedy and the United Launch Alliance Atlas V dual engine Centaur that will launch Starliner will be shipped to Cape Canaveral Air Force Station in Florida in August to prepare for the upcoming flight.

Separately, SpaceX's Crew Dragon spacecraft for Demo-1 arrived to the Cape in July for final processing. Falcon 9's first and second stages for the Demo-1 mission are targeted to ship from SpaceX's headquarters in Hawthorne, California to the company's rocket testing facility in McGregor, Texas for additional testing in August.

Once the uncrewed flight tests are complete and the data reviews have validated the spacecraft systems, NASA astronauts will have their first opportunity to fly in the spacecraft. Crew for Boeing's Crew Flight Test and SpaceX's Demo-2 flights will each include at least a flight commander and pilot aboard to test out the systems.

These flight tests will have similar configurations to the uncrewed tests, but the crew will have the ability to interface with spacecraft displays, communicate with mission control, and practice manual controls during flight. Starliner and Crew Dragon will dock and undock autonomously to the space station before returning the crew safely home.

"The crew right now is actually working on integrated crew simulations on the flight systems," said Lueders. "They are providing input to the partners to help ensure the interior of the cabin is appropriately located and set up so crew can function and conduct key activities. They're verifying crew layout, doing simulations where they're actually practicing their maneuvers, and also checking out the software and the display systems, and everything else for the crew to be functioning safely in the spacecraft."

After successful completion of the flight tests with crew, NASA will review flight data to verify the systems meet the agency's safety and performance certification requirements and are ready to begin regular servicing missions to the space station.

"I see parallels between commercial crew and the early aviation industry, when government nurtured that commercial innovation," said Cowart. "In similar fashion, NASA is empowering private industry to gain solid footing in low-Earth orbit, which will allow NASA to explore new frontiers in deep space."

Thursday, August 2, 2018

Exoplanets where life could develop as on Earth

Scientists have identified a group of planets outside our solar system where the same chemical conditions that may have led to life on Earth exist. The researchers, from the University of Cambridge and the Medical Research Council Laboratory of Molecular Biology (MRC LMB), found that the chances for life to develop on the surface of a rocky planet like Earth are connected to the type and strength of light given off by its host star. Their study, published in the journal Science Advances, proposes that stars which give off sufficient ultraviolet (UV) light could kick-start life on their orbiting planets in the same way it likely developed on Earth, where the UV light powers a series of chemical reactions that produce the building blocks of life. The researchers have identified a range of planets where the UV light from their host star is sufficient to allow these chemical reactions to take place, and that lie within the habitable range where liquid water can exist on the planet's surface. "This work allows us to narrow down the best places to search for life," said Dr. Paul Rimmer, a postdoctoral researcher with a joint affiliation at Cambridge's Cavendish Laboratory and the MRC LMB, and the paper's first author. "It brings us just a little bit closer to addressing the question of whether we are alone in the universe."


The new paper is the result of an ongoing collaboration between the Cavendish Laboratory and the MRC LMB, bringing together organic chemistry and exoplanet research. It builds on the work of Professor John Sutherland, a co-author on the current paper, who studies the chemical origin of life on Earth.

In a paper published in 2015, Professor Sutherland's group at the MRC LMB proposed that cyanide, although a deadly poison, was in fact a key ingredient in the primordial soup from which all life on Earth originated.

In this hypothesis, carbon from meteorites that slammed into the young Earth interacted with nitrogen in the atmosphere to form hydrogen cyanide. The hydrogen cyanide rained to the surface, where it interacted with other elements in various ways, powered by the UV light from the Sun. The chemicals produced from these interactions generated the building blocks of RNA, the close relative of DNA which most biologists believe was the first molecule of life to carry information.

In the laboratory, Sutherland's group recreated these chemical reactions under UV lamps, and generated the precursors to lipids, amino acids and nucleotides, all of which are essential components of living cells.

"I came across these earlier experiments, and as an astronomer, my first question is always what kind of light are you using, which as chemists they hadn't really thought about," said Rimmer. "I started out measuring the number of photons emitted by their lamps, and then realised that comparing this light to the light of different stars was a straightforward next step."

The two groups performed a series of laboratory experiments to measure how quickly the building blocks of life can be formed from hydrogen cyanide and hydrogen sulphite ions in water when exposed to UV light. They then performed the same experiment in the absence of light.

"There is chemistry that happens in the dark: it's slower than the chemistry that happens in the light, but it's there," said senior author Professor Didier Queloz, also from the Cavendish Laboratory. "We wanted to see how much light it would take for the light chemistry to win out over the dark chemistry."

The same experiment run in the dark with the hydrogen cyanide and the hydrogen sulphite resulted in an inert compound which could not be used to form the building blocks of life, while the experiment performed under the lights did result in the necessary building blocks.

The researchers then compared the light chemistry to the dark chemistry against the UV light of different stars. They plotted the amount of UV light available to planets in orbit around these stars to determine where the chemistry could be activated.

They found that stars around the same temperature as our Sun emitted enough light for the building blocks of life to have formed on the surfaces of their planets. Cool stars, on the other hand, do not produce enough light for these building blocks to be formed, except if they have frequent powerful solar flares to jolt the chemistry forward step by step. Planets that both receive enough light to activate the chemistry and could have liquid water on their surfaces reside in what the researchers have called the abiogenesis zone.

Among the known exoplanets which reside in the abiogenesis zone are several planets detected by the Kepler telescope, including Kepler 452b, a planet that has been nicknamed Earth's 'cousin,' although it is too far away to probe with current technology. Next-generation telescopes, such as NASA's TESS and James Webb telescopes, will hopefully be able to identify and potentially characterise many more planets that lie within the abiogenesis zone.

Of course, it is also possible that if there is life on other planets, that it has or will develop in a totally different way than it did on Earth.

"I'm not sure how contingent life is, but given that we only have one example so far, it makes sense to look for places that are most like us," said Rimmer. "There's an important distinction between what is necessary and what is sufficient. The building blocks are necessary, but they may not be sufficient: it's possible you could mix them for billions of years and nothing happens. But you want to at least look at the places where the necessary things exist."

According to recent estimates, there are as many as 700 million trillion terrestrial planets in the observable universe. "Getting some idea of what fraction have been, or might be, primed for life fascinates me," said Sutherland. "Of course, being primed for life is not everything and we still don't know how likely the origin of life is, even given favourable circumstances - if it's really unlikely then we might be alone, but if not, we may have company."