(5 August 2020 – Space Dynamics Laboratory) The Space Dynamics Laboratory (SDL) has announced that it was recently awarded a contract for two smallsat radios for a NASA asteroid mission — the contract value has not been disclosed.
Making long-distance calls from deep space is technologically challenging even with large spacecraft, and from smallsats, it becomes exponentially challenging. The SDL-built Iris radios will provide communications for dual Lockheed Martin small spacecraft being built for NASA’s deep space mission called Janus, to visit near-Earth asteroids, which is led by principal investigator Dr. Daniel Scheeres from the University of Colorado Boulder.
SDL’s Iris radio (courtesy: SDL)
The Janus mission is targeted for launch in August 2022 and will travel more than 10 million kilometers to meet up with the pair of binary asteroids designated 1991 VH and 1996 FG3. The unique asteroid systems consisting of a primary and secondary body are considered rubble piles, made up of many pieces of space rock that have joined together under the influence of gravity.
Scheeres and fellow Janus scientists will study the pair of asteroids to better understand the formation and evolutionary implication of small rubble pile asteroids and build more accurate models for asteroid parameters and evolution.
In deep space, communications for the two miniature spacecraft will be critical to the success of the Janus mission. The Iris radios are designed for just this task — to provide a unique communications architecture to relay valuable mission data through NASA’s Deep Space Network to the mission operations center at Lockheed Martin in Denver.
Developed and operated by NASA’s Jet Propulsion Laboratory, the DSN is a global array of very large radio antennas that supports interplanetary spacecraft missions. According to NASA, the DSN also provides radar and radio astronomy observations that improve our understanding of the solar system and the larger universe.
Weighing only 1.1 kilograms, and about the size of a half loaf of bread, the Iris radios will use environmentally robust architecture, including radiation-tolerant parts necessary for deep-space communication over multiple years at a fraction of the mass and cost of other radios with similar reliability and capability. The design incorporates advanced thermal management necessary for navigation tracking.
Janus was selected as part of NASA’s Small Innovative Missions for Planetary Exploration. SIMPLEx programs are intended to contribute to NASA’s goal of boosting comprehension of our solar system’s makeup, provenance and evolution. They will also support planetary defense and help fill in knowledge gaps as NASA moves forward with its plans for human exploration of the Moon and Mars, according to the space agency.
“SDL is honored to be a part of this exciting mission under the leadership of Dr. Scheeres that will provide scientists with unprecedented information from small spacecraft about the workings of our solar system. Janus will add valuable insight on communication systems for future SmallSat deep-space programs,” said Tim Neilsen, SDL’s Iris program manager for the Janus mission. “SDL will build upon the flight-proven heritage of Iris radios and our decades-long legacy collaborating with NASA to ensure mission success.”
Rocket Lab completes final dress rehearsal at Launch Complex 2 ahead of first Electron mission from U.S. soil
(17 September 2020 – Rocket Lab) Rocket Lab has successfully completed a wet dress rehearsal of the Electron vehicle at Rocket Lab Launch Complex 2 (LC-2) at the Mid-Atlantic Regional Spaceport in Wallops Island, Virginia.
With this major milestone complete, the Electron launch vehicle, launch team, and the LC-2 pad systems are now ready for Rocket Lab’s first launch from U.S. soil. The mission is a dedicated launch for the United States Space Force in partnership with the Department of Defense’s Space Test Program and the Space and Missile Systems Center’s Small Launch and Targets Division.
(courtesy: Rocket Lab)
The wet dress rehearsal is a crucial final exercise conducted by the launch team to ensure all systems and procedures are working perfectly ahead of launch day. The Electron launch vehicle was rolled out to the pad, raised vertical and filled with high grade kerosene and liquid oxygen to verify fueling procedures. The launch team then flowed through the integrated countdown to T-0 to carry out the same operations they will undertake on launch day. Before a launch window can be set, NASA is conducting the final development and certification of its Autonomous Flight Termination System (AFTS) software for the mission. This flight will be the first time an AFTS has been has flown from the Mid-Atlantic Regional Spaceport and represents a valuable new capability for the spaceport.
Launch Complex 2 supplements Rocket Lab’s existing site, Launch Complex 1 in New Zealand, from which 14 Electron missions have already launched. The two launch complexes combined can support more than 130 launch opportunities every year to deliver unmatched flexibility for rapid, responsive launch to support a resilient space architecture. Operating two launch complexes in diverse geographic locations provides an unrivalled level of redundancy and assures access to space regardless of disruption to any one launch site.
“Responsive launch is the key to resilience in space and this is what Launch Complex 2 enables,” said Peter Beck, Rocket Lab founder and Chief Executive. “All satellites are vulnerable, be it from accidental or deliberate actions. By operating a proven launch vehicle from two launch sites on opposite sides of the world, Rocket Lab delivers unmatched flexibility and responsiveness for the defense and national security community to quickly replace any disabled satellite. We’re immensely proud to be delivering reliable and flexible launch capability to the U.S. Space Force and the wider defense community as space becomes an increasingly contested domain.”
While the launch team carried out this week’s wet dress rehearsal, construction is nearing completion on the Rocket Lab Integration and Control Facility (ICF) within the Wallops Research Park, adjacent to NASA Wallops Flight Facility Main Base. The ICF houses a launch control center, state-of-the-art payload integration facilities, and a vehicle integration department that enables the processing of multiple Electron vehicles to support multiple launches in rapid succession. The build has been carried out in just a few short months thanks to the tireless support of Virginia Space, Governor Northam, Virginia Secretary of Transportation Shannon Valentine, and Accomack County.
NASA technology enables precision landing without a pilot
(17 September 2020 – NASA) Some of the most interesting places to study in our solar system are found in the most inhospitable environments – but landing on any planetary body is already a risky proposition.
With NASA planning robotic and crewed missions to new locations on the Moon and Mars, avoiding landing on the steep slope of a crater or in a boulder field is critical to helping ensure a safe touch down for surface exploration of other worlds. In order to improve landing safety, NASA is developing and testing a suite of precise landing and hazard-avoidance technologies.
A new suite of lunar landing technologies, called Safe and Precise Landing – Integrated Capabilities Evolution (SPLICE), will enable safer and more accurate lunar landings than ever before. Future Moon missions could use NASA’s advanced SPLICE algorithms and sensors to target landing sites that weren’t possible during the Apollo missions, such as regions with hazardous boulders and nearby shadowed craters. SPLICE technologies could also help land humans on Mars. (courtesy: NASA)
A combination of laser sensors, a camera, a high-speed computer, and sophisticated algorithms will give spacecraft the artificial eyes and analytical capability to find a designated landing area, identify potential hazards, and adjust course to the safest touchdown site. The technologies developed under the Safe and Precise Landing – Integrated Capabilities Evolution (SPLICE) project within the Space Technology Mission Directorate’s Game Changing Development program will eventually make it possible for spacecraft to avoid boulders, craters, and more within landing areas half the size of a football field already targeted as relatively safe.
Three of SPLICE’s four main subsystems will have their first integrated test flight on a Blue Origin New Shepard rocket during an upcoming mission. As the rocket’s booster returns to the ground, after reaching the boundary between Earth’s atmosphere and space, SPLICE’s terrain relative navigation, navigation Doppler lidar, and descent and landing computer will run onboard the booster. Each will operate in the same way they will when approaching the surface of the Moon.
The fourth major SPLICE component, a hazard detection lidar, will be tested in the future via ground and flight tests.
The New Shepard (NS) booster lands after this vehicle’s fifth flight during NS-11 May 2, 2019. (courtesy: Blue Origin)
When a site is chosen for exploration, part of the consideration is to ensure enough room for a spacecraft to land. The size of the area, called the landing ellipse, reveals the inexact nature of legacy landing technology. The targeted landing area for Apollo 11 in 1968 was approximately 11 miles by 3 miles, and astronauts piloted the lander. Subsequent robotic missions to Mars were designed for autonomous landings. Viking arrived on the Red Planet 10 years later with a target ellipse of 174 miles by 62 miles.
The Apollo 11 landing ellipse, shown here, was 11 miles by 3 miles. Precision landing technology will reduce landing area drastically, allowing for multiple missions to land in the same region. (courtesy: NASA)
Technology has improved, and subsequent autonomous landing zones decreased in size. In 2012, the Curiosity rover landing ellipse was down to 12 miles by 4 miles.
Being able to pinpoint a landing site will help future missions target areas for new scientific explorations in locations previously deemed too hazardous for an unpiloted landing. It will also enable advanced supply missions to send cargo and supplies to a single location, rather than spread out over miles.
Each planetary body has its own unique conditions. That’s why “SPLICE is designed to integrate with any spacecraft landing on a planet or moon,” said project manager Ron Sostaric. Based at NASA’s Johnson Space Center in Houston, Sostaric explained the project spans multiple centers across the agency.
“What we’re building is a complete descent and landing system that will work for future Artemis missions to the Moon and can be adapted for Mars,” he said. “Our job is to put the individual components together and make sure that it works as a functioning system.”
Atmospheric conditions might vary, but the process of descent and landing is the same. The SPLICE computer is programmed to activate terrain relative navigation several miles above the ground. The onboard camera photographs the surface, taking up to 10 pictures every second. Those are continuously fed into the computer, which is preloaded with satellite images of the landing field and a database of known landmarks.
Algorithms search the real-time imagery for the known features to determine the spacecraft location and navigate the craft safely to its expected landing point. It’s similar to navigating via landmarks, like buildings, rather than street names.
In the same way, terrain relative navigation identifies where the spacecraft is and sends that information to the guidance and control computer, which is responsible for executing the flight path to the surface. The computer will know approximately when the spacecraft should be nearing its target, almost like laying breadcrumbs and then following them to the final destination.
This process continues until approximately four miles above the surface.
NASA’s navigation Doppler lidar instrument is comprised of a chassis, containing electro-optic and electronic components, and an optical head with three telescopes. (courtesy: NASA)
Knowing the exact position of a spacecraft is essential for the calculations needed to plan and execute a powered descent to precise landing. Midway through the descent, the computer turns on the navigation Doppler lidar to measure velocity and range measurements that further add to the precise navigation information coming from terrain relative navigation. Lidar (light detection and ranging) works in much the same way as a radar but uses light waves instead of radio waves. Three laser beams, each as narrow as a pencil, are pointed toward the ground. The light from these beams bounces off the surface, reflecting back toward the spacecraft.
The travel time and wavelength of that reflected light are used to calculate how far the craft is from the ground, what direction it’s heading, and how fast it’s moving. These calculations are made 20 times per second for all three laser beams and fed into the guidance computer.
Doppler lidar works successfully on Earth. However, Farzin Amzajerdian, the technology’s co-inventor and principal investigator from NASA’s Langley Research Center in Hampton, Virginia, is responsible for addressing the challenges for use in space.
Langley engineer John Savage inspects a section of the navigation Doppler lidar unit after its manufacture from a block of metal. (courtesy: NASA/David C. Bowman)
“There are still some unknowns about how much signal will come from the surface of the Moon and Mars,” he said. If material on the ground is not very reflective, the signal back to the sensors will be weaker. But Amzajerdian is confident the lidar will outperform radar technology because the laser frequency is orders of magnitude greater than radio waves, which enables far greater precision and more efficient sensing.
The workhorse responsible for managing all of this data is the descent and landing computer. Navigation data from the sensor systems is fed to onboard algorithms, which calculate new pathways for a precise landing.
SPLICE hardware undergoing preparations for a vacuum chamber test. Three of SPLICE’s four main subsystems will have their first integrated test flight on a Blue Origin New Shepard rocket. (courtesy: NASA)
The descent and landing computer synchronizes the functions and data management of individual SPLICE components. It must also integrate seamlessly with the other systems on any spacecraft. So, this small computing powerhouse keeps the precision landing technologies from overloading the primary flight computer.
The computational needs identified early on made it clear that existing computers were inadequate. NASA’s high-performance spaceflight computing processor would meet the demand but is still several years from completion. An interim solution was needed to get SPLICE ready for its first suborbital rocket flight test with Blue Origin on its New Shepard rocket. Data from the new computer’s performance will help shape its eventual replacement.
John Carson, the technical integration manager for precision landing, explained that “the surrogate computer has very similar processing technology, which is informing both the future high-speed computer design, as well as future descent and landing computer integration efforts.”
Looking forward, test missions like these will help shape safe landing systems for missions by NASA and commercial providers on the surface of the Moon and other solar system bodies.
“Safely and precisely landing on another world still has many challenges,” said Carson. “There’s no commercial technology yet that you can go out and buy for this. Every future surface mission could use this precision landing capability, so NASA’s meeting that need now. And we’re fostering the transfer and use with our industry partners.”
Thales Alenia Space to provide key technology to HERA, ESA’s planetary defence mission
(15 September 2020 – Thales) Thales Alenia Space has been selected by OHB, prime contractor, and the European Space Agency (ESA), to provide the Communications system as well as the Power Conditioning and Distribution Unit (PCDU) for the HERA mission.
Named after the Greek goddess of marriage, HERA, European contribution to AIDA international cooperation (Asteroid Impact & Deflection Assessment, the first planetary defence mission of humanity), aims to find out if we are capable of deflecting an asteroid and prevent it from hitting Earth. AIDA consists of two missions, NASA’s Double Asteroid Redirection Test (DART), a kinetic impactor designed to deviate the orbit of the smaller of the two Didymos asteroids, and ESA’s HERA inspector spacecraft, that will rendez-vous the Didymos target asteroid about 4 years after the DART impact. HERA, scheduled for launch in 2024, will travel for the first time in history to explore a binary asteroid system.
The systems provided by Thales Alenia Space will be key to the mission, allowing to control and track the spacecraft from a distance up to 500 million kilometer far away, to send all the information gathered by HERA back to Earth and to perform radio science. Thales Alenia Space in Spain will be responsible for the X-band Communications System, leading an industrial consortium which includes Thales Alenia Space in Italy, responsible for the state-of-art Deep Space Transponder that, exploiting a flight-proven digital platform, will allow robust communication with the Ground Station, and Thales Alenia Space in Belgium, responsible for the Travelling Wave Tube Amplifiers (TWTA), among other companies. Thales Alenia Space in Belgium will also provide the PCDU, the electrical core of the spacecraft.
Eduardo Bellido, CEO of Thales Alenia Space in Spain, said: “It is exciting to be part of this historic experiment for humanity to protect the Earth against asteroid collisions. Our technology will deliver essential data to scientists to be able to establish a planetary defence strategy based on asteroids deflection, to prevent the threat of an impact on Earth. Landing on Titan, mapping the Universe with Herschel and Planck, hunting a comet with Rosetta and now preventing Earth against Asteroid, all so amazing and unimaginable challenges our company is so proud to face”.
HERA will send key information to Earth on the physical properties of Dimorphos, (including mass, size, shape, volume, density, porosity, size distribution of surface material) to determine the momentum transfer efficiency of the impact and to allow scaling it to different asteroids; details of the crater formed by the impact to improve our understanding of the cratering process; and observations on the subtle dynamic effects that are difficult to detect from ground-based observations.
Thales Alenia Space is the European leader in satellite communication systems, in particular with a strong heritage in Spain in TT&C and data transmission systems for all type of space missions, including missions in low Earth Orbit (Sentinel 1-2-3, Ingenio, FLEX), geostationary orbit (GEO-KOMPSAT-2, MTG), lunar orbit (KPLO, NOVA-C, Viper) and space telescopes orbiting around the L2 Lagrangian point (Herschel, Planck, Euclid, WFIRST, PLATO). Furthermore, Thales Alenia Space, through its Italian footprint, is a worldwide leader for Integrated Transponders operating in different frequency bands and for different applications, i.e.: Earth Observation (COSMO constellation), Secure Communications, Solar System exploration (Rosetta, Mars Express, Venus Express, BepiColombo, JUNO, ExoMars, Solar Orbiter, JUICE, Mars Moon Explorer), and Scientific missions in Lagrangian orbit (Gaia, Lisa Pathfinder, JWST, EUCLID, PLATO).
Saving our planet
Asteroids are bodies originated in the young stars nebulae that never grew to planets, formed of rock and metal. Among them, those that have an orbit that brings them close to Earth, known as near-Earth asteroids, pose a risk of hitting the Earth. There are plenty of such bodies in our Solar system, from tiny little ones measuring a few meters (there’s 40-50 millions of them) up to larger ones, measuring more than 1 km but much more scarce (there’s less than 1000 of them).
Neither the smaller near-Earth asteroids nor the larger ones pose a real threat to humanity. Small asteroids actually hit the Earth quite frequently (every two weeks) with no consequences. The larger ones, although potentially dangerous, are well-known and tracked, and it takes millions of years to have one of them hitting the Earth. Actually, a 10km asteroid impact is the most accepted theory of the Cretaceous extinction around 66 million years ago, ending with three-quarters of the plant and animal species, among others the dinosaurs. Another famous asteroid impact was Tunguska in Siberia in 1908, presumably belonging to the 30 to 100 meter class, which hit the Earth every 10 years.
It is the mid-sized class asteroids of more than 100 meters the ones we need to worry about, such as the asteroid HERA will explore. There are about 30,000 near-Earth asteroids of the 100 to 300 meter size class, 82% of them still to be spotted, hitting the Earth every 10,000 years. The impact energy of such an asteroid is equivalent to around 50 megatons of TNT, the power of a “Tsar Bomba”. The effect of such an impact would be devastating if it reached a populated area, capable to destroy an entire city or to create a tsunami if it impacted a sea.
The Didymos binary asteroid system is prototypical of the thousands of asteroids that pose a hazardous risk of impact to our planet. Around the main body, 780 meter in diameter (the size of a mountain), orbits a 160 meter moonlet, Dimorphos, similar in size to the great pyramid of Giza. HERA will target this moonlet, which will become the smallest asteroid ever visited by a probe.
The DART spacecraft will be launched in July 2021 and is expected to hit the surface of Dimorphos on September 2022 at a speed of almost 7 kilometers per second, which is expected to modify its orbit around Didymos and create a substantial crater. Dimorphos will thus become the first object in the Solar System whose orbit and physical characteristics have been measurably modified by human effort.
The HERA spacecraft will reach the binary asteroid by the end of 2026, and during 6 months it will perform a detailed study mapping the impact crater caused by DART and measuring the mass and other physical properties of the asteroid to determine the effect of the impact on its orbit. Thus, the data provided by HERA will allow, for the first time, to validate and refine the numerical impact models at the asteroid scale, thus making this deflection technique ready for use for planetary defense if it were ever necessary to safeguard the Earth.
About Thales Alenia Space
Drawing on over 40 years of experience and a unique combination of skills, expertise and cultures, Thales Alenia Space delivers cost-effective solutions for telecommunications, navigation, Earth observation, environmental management, exploration, science and orbital infrastructures. Governments and private industry alike count on Thales Alenia Space to design satellite-based systems that provide anytime, anywhere connections and positioning, monitor our planet, enhance management of its resources, and explore our Solar System and beyond. Thales Alenia Space sees space as a new horizon, helping to build a better, more sustainable life on Earth. A joint venture between Thales (67%) and Leonardo (33%), Thales Alenia Space also teams up with Telespazio to form the parent companies’ Space Alliance, which offers a complete range of services. Thales Alenia Space posted consolidated revenues of approximately 2.15 billion euros in 2019 and has around 7,700 employees in nine countries.