Cubesat offers template for future astronomy missions

The first NASA-funded small satellite for exoplanet science is continuing to gather data well beyond its expected lifetime. The Colorado Ultraviolet Transit Experiment, known as CUTE, a six-unit cubesat equipped with a telescope to funnel data to a spectrograph, traveled to sun-synchronous low-Earth orbit in September 2021 as a secondary payload on the NASA- U.S. Geological Survey Landsat 9 Earth-observation mission. CUTE was designed to operate in space for at least eight months. Twenty-seven months later, the satellite’s onboard instruments still are observing the dramatic atmospheric loss of “hot jupiters,” gas giants orbiting very close to bright stars. “This atmospheric escape is incredibly fast,” said Kevin France, CUTE principal investigator at the University of Colorado’s Laboratory for Atmospheric and Space Physics (LASP), which assembled, tested and operates the satellite. “The materials are coming out so fast that they are dragging all the heavy elements out of the atmosphere with them.” Based on CUTE’s success, two additional NASA-funded, LASP-led missions have adopted similar mission and instrument designs. “CUTE’s been a great success, particularly given that we didn’t really know if we could do it for the amount of money that we proposed,” France told SpaceNews at the American Geophysical Union conference here. Lessons learned from CUTE are helping researchers “figure out how to build small spacecraft, how to build small instruments and how to have a student-led team,” France said.

The Colorado Ultraviolet Transit Experiment, known as CUTE, is a cubesat launched in 2021 to characterize the composition and mass-loss rates of exoplanet atmospheres. Credit: University of Colorado Laboratory for Atmospheric and Space Physics

Smallsat Astronomy

The budget for developing, assembling and operating CUTE through the summer of 2024 is about $5.5 million.

“At this cost, we’re still figuring out how to make things work,” France said. “So, working and doing science is batting above your average.”

The missions mimicking CUTE are 12-unit cubesats Sprite and Mantis.

Sprite, which stands for Supernova remnants Proxies for Reionization and Integrated Testbed Experiment, is scheduled for launch in 2024. The $4 million mission will study how gas and dust is processed in galaxies and how energetic ionizing radiation is transported from stars to the intergalactic medium between galaxies.

Mantis, short for Monitoring Activity from Nearby sTars with uv Imaging and Spectroscopy, is an $8.5 million campaign to observe how high-energy radiation from stars influences the habitability of planets.

Ingenuity and Chance

CUTE remains operational more than two years after launch thanks to ingenuity and luck.

The tiny satellite was sent into orbit at a higher altitude than mission planners expected. As a result, CUTE is expected to reenter Earth’s atmosphere in 2027, instead of late this year as originally scheduled.

Additional time in orbit means extra wear and tear on hardware.

“Every time we have a problem, we figure out a new way to operate the spacecraft,” France said.

When the satellite’s primary and backup memory storage cards failed, for example, mission operators learned to communicate directly with CUTE’s scientific payload.

“We send the data down directly from the science payload to the ground and we bypass the spacecraft altogether,” France said.

Distant Galaxies

Cubesats have been widely adopted for civil and commercial space missions since LASP researchers proposed CUTE in 2016.

At the time, “we were beginning to believe we could study the sun and Earth’s upper atmosphere with cubesats,” France said. “But the idea that we could be pointed at targets that are 300, 400 light years away and do high-precision astronomical measurements from the cubesat was ambitious.”

Now that CUTE has shown the potential, small satellites could play key roles in observing distant galaxies, black holes “and all the other things that we’re interested in studying,” France said.

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).