Summer road trip for Curiosity rover has begun

NASA's Curiosity Mars rover has started a road trip that will continue through the summer across roughly a mile (1.6 kilometers) of terrain. By trip's end, the rover will be able to ascend to the next section of the 3-mile-tall Martian (5-kilometer-tall) mountain it's been exploring since 2014, searching for conditions that may have supported ancient microbial life. Located on the floor of Gale Crater, Mount Sharp is composed of sedimentary layers that built up over time. Each layer helps tell the story about how Mars changed from being more Earth-like - with lakes, streams and a thicker atmosphere - to the nearly-airless, freezing desert it is today. The rover's next stop is a part of the mountain called the "sulfate-bearing unit." Sulfates, like gypsum and Epsom salts, usually form around water as it evaporates, and they are yet another clue to how the climate and prospects for life changed nearly 3 billion years ago. But between the rover and those sulfates lies a vast patch of sand that Curiosity must drive around to avoid getting stuck. Hence the mile-long road trip: Rover planners, who are commanding Curiosity from home rather than their offices at NASA's Jet Propulsion Laboratory in Southern California, expect to reach the area in early fall, although the science team could decide to stop along the way to drill a sample or study any surprises they come across. Depending on the landscape, Curiosity's top speeds range between 82 and 328 feet (25 and100 meters) per hour. Some of this summer road trip will be completed using the rover's automated driving abilities, which enable Curiosity to find the safest paths forward on its own. Rover planners allow for this when they lack terrain imagery. (Planners hope for more autonomy in the future; in fact, you can help train an algorithm that identifies Martian drive paths.)

"Curiosity can't drive entirely without humans in the loop," said Matt Gildner, lead rover driver at JPL. "But it does have the ability to make simple decisions along the way to avoid large rocks or risky terrain. It stops if it doesn't have enough information to complete a drive on its own."

In journeying to the "sulfate-bearing unit," Curiosity leaves behind Mount Sharp's "clay-bearing unit," which the robotic scientist had been investigating on the lower side of the mountain since early 2019. Scientists are interested in the watery environment that formed this clay and whether it could have supported ancient microbes.

Extending across both the clay unit and the sulfate unit is a separate feature: the "Greenheugh Pediment," a slope with a sandstone cap. It likely represents a major transition in the climate of Gale Crater. At some point, the lakes that filled the 96-mile-wide (154-kilometer-wide) crater disappeared, leaving behind sediments that eroded into the mountain we see today. The pediment formed later (though whether from wind or water erosion remains unknown); then windblown sand blanketed its surface, building into the sandstone cap.

The northern end of the pediment spans the clay region, and though the slope is steep, the rover's team decided to ascend Greenheugh back in March for a preview of terrain they'll see later in the mission. As Curiosity peeked over the top, scientists were surprised to find small bumps along the sandstone surface.

"Nodules like these require water in order to form," said Alexander Bryk, a doctoral student at University of California, Berkeley who led the pediment detour. "We found some in the windblown sandstone on top of the pediment and some just below the pediment. At some point after the pediment formed, water seems to have returned, altering the rock as it flowed through it."

These bumps may look familiar to Mars rover fans: One of Curiosity's predecessors, the Opportunity rover, found similar geologic textures dubbed "blueberries" back in 2004. Nodules have become a familiar sight throughout Mount Sharp, though these newly discovered ones are different in composition from what Opportunity found. They suggest water was present in Gale long after the lakes disappeared and the mountain took its present shape. The discovery extends the period when the crater hosted conditions capable of supporting life, if it ever was present.

"Curiosity was designed to go beyond Opportunity's search for the history of water," said Abigail Fraeman of JPL, who has served as deputy project scientist for both missions. "We're uncovering an ancient world that offered life a foothold for longer than we realized."

A binary star as a cosmic particle accelerator

With a specialised telescope in Namibia a DESY-led team of researchers has proven a certain type of binary star as a new kind of source for very high-energy cosmic gamma-radiation. Eta Carinae is located 7500 lightyears away in the constellation Carina (the ship's keel) in the Southern Sky and, based on the data collected, emits gamma rays with energies all the way up to 400 gigaelectronvolts (GeV), some 100 billion times more than the energy of visible light. The team headed by DESY's Stefan Ohm, Eva Leser and Matthias Fubling is presenting its findings, made at the gamma-ray observatory High Energy Stereoscopic System (H.E.S.S.), in the journal Astronomy and Astrophysics. An accompanying multimedia animation explains the phenomenon. "With such visualisations we want to make the fascination of research tangible," emphasises DESY's Director of Astroparticle Physics, Christian Stegmann. Eta Carinae is a binary system of superlatives, consisting of two blue giants, one about 100 times, the other about 30 times the mass of our sun. The two stars orbit each other every 5.5 years in very eccentric elliptical orbits, their separation varying approximately between the distance from our Sun to Mars and from the Sun to Uranus. Both these gigantic stars fling dense, supersonic stellar winds of charged particles out into space. In the process, the larger of the two loses a mass equivalent to our entire Sun in just 5000 years or so. The smaller one produces a fast stellar wind travelling at speeds around eleven million kilometres per hour (about one percent of the speed of light).

A huge shock front is formed in the region where these two stellar winds collide, heating up the material in the wind to extremely high temperatures. At around 50 million degrees Celsius, this matter radiates brightly in the X-ray range. The particles in the stellar wind are not hot enough to emit gamma radiation, though.

"However, shock regions like this are typically sites where subatomic particles are accelerated by strong prevailing electromagnetic fields," explains Ohm, who is the head of the H.E.S.S. group at DESY. When particles are accelerated this rapidly, they can also emit gamma radiation. In fact, the satellites "Fermi", operated by the US space agency NASA, and AGILE, belonging to the Italian space agency ASI, already detected energetic gamma rays of up to about 10 GeV coming from Eta Carinae in 2009.

"Different models have been proposed to explain how this gamma radiation is produced," Fubling reports. "It could be generated by accelerated electrons or by high-energy atomic nuclei."

Determining which of these two scenarios is correct is crucial: very energetic atomic nuclei account for the bulk of the so-called Cosmic Rays, a subatomic cosmic hailstorm striking Earth constantly from all directions. Despite intense research for more than 100 years, the sources of the Cosmic Rays are still not exhaustively known.

Since the electrically charged atomic nuclei are deflected by cosmic magnetic fields as they travel through the universe, the direction from which they arrive at Earth no longer points back to their origin. Cosmic gamma rays, on the other hand, are not deflected. So, if the gamma rays emitted by a specific source can be shown to originate from high-energy atomic nuclei, one of the long-sought accelerators of cosmic particle radiation will have been identified.

"In the case of Eta Carinae, electrons have a particularly hard time getting accelerated to high energyies, because they are constantly being deflected by magnetic fields during their acceleration, which makes them lose energy again," says Leser. "Very high-energy gamma radiation begins above the 100 GeV range, which is rather difficult to explain in Eta Carinae to stem from electron acceleration."

The satellite data already indicated that Eta Carinae also emits gamma radiation beyond 100 GeV, and H.E.S.S. has now succeeded in detecting such radiation up to energies of 400 GeV around the time of the close encounter of the two blue giants in 2014 and 2015. This makes the binary star the first known example of a source in which very high-energy gamma radiation is generated by colliding stellar winds.

"The analysis of the gamma radiation measurements taken by H.E.S.S. and the satellites shows that the radiation can best be interpreted as the product of rapidly accelerated atomic nuclei," says DESY's PhD student Ruslan Konno, who has published a companion study, together with scientists from the Max Planck Institute for Nuclear Physics in Heidelberg.

"This would make the shock regions of colliding stellar winds a new type of natural particle accelerator for cosmic rays." With H.E.S.S., which is named after the discoverer of Cosmic Rays, Victor Franz Hess, and the upcoming Cherenkov Telescope Array (CTA), the next-generation gamma-ray observatory currently being built in the Chilean highlands, the scientists hope to investigate this phenomenon in greater detail and discover more sources of this kind.

Thanks to detailed observations of Eta Carinae at all wavelengths, the properties of the stars, their orbits and stellar winds have been determined relatively accurately. This has given astrophysicists a better picture of the binary star system and its history.

To illustrate the new observations of Eta Carinae, the DESY astrophysicists have produced a video animation together with the animation specialists of the award-winning Science Communication Lab. The computer-generated images are close to reality because the measured orbital, stellar and wind parameters were used for this purpose. The internationally acclaimed multimedia artist Carsten Nicolai, who uses the pseudonym Alva Noto for his musical works, created the sound for the animation.

"I find science and scientific research extremely important," says Nicolai, who sees close parallels in the creative work of artists and scientists. For him, the appeal of this work also lay in the artistic mediation of scientific research results: "particularly the fact that it is not a film soundtrack, but has a genuine reference to reality," emphasizes the musician and artist.

Together with the exclusively composed sound, this unique collaboration of scientists, animation artists and musician has resulted in a multimedia work that takes viewers on an extraordinary journey to a superlative double star some 7500 light years away.

DESY is one of the world's leading particle accelerator centres and investigates the structure and function of matter - from the interaction of tiny elementary particles and the behaviour of novel nanomaterials and vital biomolecules to the great mysteries of the universe. The particle accelerators and detectors that DESY develops and builds at its locations in Hamburg and Zeuthen are unique research tools.

They generate the most intense X-ray radiation in the world, accelerate particles to record energies and open up new windows onto the universe. DESY is a member of the Helmholtz Association, Germany's largest scientific association, and receives its funding from the German Federal Ministry of Education and Research (BMBF) (90 per cent) and the German federal states of Hamburg and Brandenburg (10 per cent).

UK Govt to acquire OneWeb satellite constellation

The Government has today (3 July) led a successful bid to acquire OneWeb, which develops cutting-edge satellite technology in the UK and in the US. The move signals the Government's ambition for the UK to be a pioneer in the research, development, manufacturing, and exploitation of novel satellite technologies through the ownership of a fleet of Low Earth orbit satellites. Business Secretary Alok Sharma confirmed that the Government will invest $500million and take a significant equity share in OneWeb. This is alongside Bharti Global Ltd, which is part of a group that controls the third largest mobile operator in the world. Bharti will provide the company commercial and operational leadership, and bring OneWeb a revenue base to contribute towards its future success. The deal will enable the company to complete construction of a global satellite constellation that will provide enhanced broadband and other services to countries around the world. The deal also offers the UK strategic opportunities across a wide range of other applications, working with our international allies. With a sovereign global satellite system, the UK will further develop its advanced manufacturing base, making the most of its highly skilled workforce as the hardware is further developed and equipment and services are deployed to make the most of this unique capability. OneWeb will also contribute to the Government's plan to join the first rank of space nations, along with our commitment to making the UK a world leader in science, research and development. The deal is subject to US court approval and regulatory clearances and is expected to close before the end of the year.

It follows the formation of the UK's first-ever National Space Council, chaired by the Chancellor of the Exchequer, to consider how space policy can enhance the country's prosperity and place in the world, as well as our wider national security interests.

Business Secretary Alok Sharma said: "This deal underlines the scale of Britain's ambitions on the global stage.

"Our access to a global fleet of satellites has the potential to connect millions of people worldwide to broadband, many for the first time, and the deal presents the opportunity to further develop our strong advanced manufacturing base right here in the UK."

The UK space sector is an economic success story, growing by over 60 per cent since 2010. The sector, which already supports 300 billion pounds of UK economic activity through the use of satellite services, is expected to grow further as new commercial opportunities are unlocked by this agreement.

OneWeb was formed in 2012, and has been developing cutting-edge satellite technology from its bases both here in the UK and in the United States.

The UK Government will have a final say over any future sale of the company, and over future access to OneWeb technology by other countries on national security grounds.

Airbus signs contract with Optus for OneSat

Airbus Defence and Space has won a contract for a fully reconfigurable telecomunications satellite from Australia's second largest telecommunications company and leading satellite operator Optus. The satellite will be based on Airbus' new standard OneSat product line and is Airbus' first contract from the Australian operator. Airbus will deliver an end-to-end solution, including design and manufacture of the Optus 11 spacecraft, as well as an advanced digital suite to manage the digital payload and operate the end-to-end satellite resources, providing Optus with a turnkey system and the ability to add hosted payloads such as SBAS. What sets Optus 11 apart is its ability to adjust its coverage, capacity and frequency, through on board processing and active antennas with beam forming capability. It will deliver power and bandwidth dynamically to strengthen capacity and resilience of Optus fleet and enable Optus to configure and adapt the payload mission to end-user needs, taking advantage of the latest innovations in payload and resource management. Optus 11 will deliver a combination of broadcast and broadband VHTS missions in Ku band over Australia and New Zealand, to improve Direct to Home broadcasting over the Australasia region, increase reach in the Antarctic and Pacific zones and support growth into mobile markets, helping eliminate connectivity black spots through the Australian Government's Mobile Black Spot programme.

Airbus' Head of Space Systems, Jean-Marc Nasr said: "We are grateful to Optus for their trust in Airbus in a region where we have ambitions to work with local industry to support space technology development in both the civil and defence sectors."

"OneSat is a truly disruptive product, both from a manufacturing, and operational point of view, and gives customers the flexibility they need to serve their markets. This contract from Australia's leading satellite operator, Optus, is a ringing endorsement that our R and D strategy in developing innovative products is the right one. OneSat's high flexibility, very compact design and accelerated production should see the satellite in orbit for Optus in 2023."

Airbus' 'ready-made' OneSat satellite builds on the company's heritage from its highly reliable Eurostar telecommunications satellites, which have clocked up more than 800 years of successful operation in orbit.

This order further strenghtens Airbus' leadership in new generation reconfigurable telecommunications satellites and enables Optus with the option to add additional spacecraft in the near future.

The investments made by Airbus and its partners in very innovative OneSat developments are supported by the European Space Agency and national agencies, in particular the UK and French space agencies.

Vega Flight VV16 postponed until August

Due to the persistence of exceptionally unfavorable winds at altitude over the Guiana Space Center, Vega Flight VV16 - originally scheduled for June 18, 2020 - was repeatedly postponed, despite full availability the launcher and the 53 satellites on this Small Spacecraft Mission Service (SSMS) mission. With no improvement in the weather situation expected during the short term, Arianespace has decided to postpone Flight VV16 until August 17, 2020, when the forecast is expected to be more favorable based on modeling of the winds. The interim period will be used to recharge batteries of the launcher and the satellites, under all the required safety conditions. Despite this delay, Arianespace is maintaining the target of performing three Vega launches during 2020. Arianespace's next confirmed launch is Flight VA253, planned for July 28. This Ariane 5 mission to geostationary transfer orbit will be performed on behalf of the following customers: Intelsat (with the Galaxy 30 and MEV-2 payloads), and B-SAT (with BSAT-4b). In the exceptional context of the COVID-19 crisis, Arianespace was prepared to launch the Flight VV16 mission as soon as possible after the interruption of launch campaigns at the Guiana Space Center, which was caused by the epidemic. The mobilization of Arianespace and its partners, in particular Avio (industrial prime contractor for the Vega launcher), the French CNES space agency and the European Space Agency, made it possible to envisage this launch as of June 18, 2020. Unfortunately, due to exceptionally unfavorable winds at altitude for this time of year, the launch was rescheduled several times through Sunday, June 28.

Without a foreseeable improvement in the meteorological situation to allow an authorization of the northward launch toward polar orbit in accordance with range safety rules, Arianespace decided to reschedule the next SSMS mission launch attempt for August 17. At this date, the wind forecasts - based on models observed during several years - are more favorable.

The time that is now available will be used to restore the readiness of the launcher and the SSMS mission's 53 satellites in the context of operations carried out with batteries on the launcher in the Vega Launch Zone; and with batteries on the satellites, conducted in the launch site's payload preparation facilities.

The launch planning for Ariane 5's Flight VA253 - to be performed for operators Intelsat and B-SAT - was confirmed on July 28. The two Intelsat satellites arrived at the Spaceport in French Guiana on Saturday, June 27. Arrival of the BSAT-4b satellite is expected on July 1st.

The availability of this launch - with its eastward trajectory towards geostationary orbit - is not affected by the high-altitude winds currently observed above the Guiana Space Center in relation to the range safety rules. Therefore, a sustained level of activity continues at the Spaceport despite the health crisis that is particularly affecting French Guiana and the American continent.

"In the context of the COVID-19 crisis, which was as exceptional as it was difficult, Arianespace and its partners - especially Avio, ESA and CNES - mobilized in an absolutely remarkable way in seizing every opportunity to launch the Flight VV16 mission," confirmed Stephane Israel, Arianespace's Chief Executive Officer.

"This mobilization made it possible to carry out the Vega campaign from end to end, and to ensure the availability of both the launcher and the SSMS mission's 53 satellites.

Unfortunately, the persistence of exceptionally unfavorable winds at altitude in relation to the safety rules forces us to reposition this mission to August 17. We understand the impatience of our 21 customers, and we share it; we will now devote all our energy to ensuring the success of the 16th Vega flight for this emblematic mission as quickly as possible."

Flight VV16 is the first European rideshare mission in the framework of the Small Spacecraft Mission Service. Proposed as part of Arianespace's launch catalog offerings, SSMS is a European project.

With funding from ESA, the SSMS dispenser structure (on which the satellite payloads are integrated) was developed by Colleferro, Italy-based Avio - which also is the Vega launcher's industrial prime contractor. The structure was manufactured by the Czech company, SAB Aerospace. The European Union also contributed to the funding of the Flight VV16 demonstration mission.

The Vega launcher remains available for launch at any time when the required safety conditions are met.

Despite the delay in Vega Flight VV16, Arianespace continues to maintain its target of three Vega launches in 2020.