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(28 July 2020 – Thales Alenia Space) Thales Alenia Space has signed a contract with the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) for the delivery of the X-Band Transceiver and X-Band Diplexer, which will ensure communications for the Volatiles Investigating Polar Exploration Rover (VIPER).

VIPER (courtesy: NASA)

A critical step to human space exploration

NASA’s lunar rover will explore the South Pole of the Moon in search for water ice and other potential resources by means of its three instruments and a 1-meter (3.28-foot) drill. The data collected by the rover will show where the Moon’s water ice is most likely to be found and easiest to access. The first water maps of the Moon will mark a critical step forward in NASA’s Artemis program to establish a sustainable human presence on the surface of the Moon later this decade. Furthermore, the exploration of lunar resources to produce oxygen and propellants could enable new mission architectures to human space exploration. The VIPER rover will be delivered to the Moon as part of NASA’s Commercial Lunar Payload Services (CLPS). With a launch foreseen in late 2023, the mission will have a duration of 100 Earth days, covering 3 cycles of lunar day and night.

Direct-to-Earth communications from the Moon surface

Thales Alenia Space in Spain will design, manufacture, test and deliver the X-Band Transceiver and X-Band Diplexer, which are responsible for the rover communications with direct links between the lunar rover and Earth over NASA’s Deep Space Network.

“We are thrilled to collaborate with NASA on the VIPER mission, which will search for water on the Moon, a critical element to future human exploration endeavors,” said Eduardo Bellido, CEO of Thales Alenia Space in Spain.

“This contract with NASA reflects our leadership in space communication systems and our competitiveness in delivering state-of-the-art communication equipment for all type of space missions to customers around the world.”

VIPER is the fourth mission to the Moon in which Thales Alenia Space in Spain participates to provide key communication equipment. Starting back in 2003 with SMART-1, the first mission to the Moon of the European Space Agency (ESA), the company also contributes to the Korea Pathfinder Lunar Orbiter (KPLO), the first step of the Korean Lunar Exploration Program, as well as to the NOVA-C lunar lander being developed by Intuitive Machines to compete for NASA CLPS awards. Building on its comprehensive heritage in the development of space communications equipment for all type of space missions, Thales Alenia Space in Spain has contributed to 600 satellites, space probes and cargo vehicles from Low Earth Orbit (LEO) to the L2 Lagrangian point at 1.5 million kilometers from the Earth.

Key partner and supplier to NASA missions

Thales Alenia Space has a long standing presence in the USA space market as key partner and supplier to commercial and institutional missions. A world leader in space communications, the company has contributed communication equipment to numerous NASA programs such as PACE, WFIRST, IBEX, OCO, Cygnus, JUNO, ICON or JWST. Thales Alenia Space is also an experienced provider of pressurized elements for human space exploration, including multiple modules of the International Space Station such as Node 2 & 3, Columbus (pressurized part), the Multi-Purpose Logistics Module (MPLM), the Permanent Logistic Module (PPM), the Cupola and the ATV and Cygnus resupply cargo vehicle. Moreover, the company’s long-standing capabilities in oceanography and altimetry are born with the Topex-Poseidon joint NASA/CNES (French Space Agency) program, to be followed by the Jason oceanographic satellites series. Thales Alenia Space is now teaming up with the French space agency and NASA/JPL on SWOT, a very ambitious American-French program that will shape the future of space-based oceanography.

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.

About Thales Alenia Space in Spain

Thales Alenia Space is well represented in Spain and is the country’s leading space company in the satellite segment, with 31 years of experience in the design, development and sale of advanced space systems and equipment. It has contributed to 600 satellites, space probes and vehicles used in telecommunications, Earth observation, science, exploration, navigation and orbital infrastructure missions, and delivered more than 4000 equipment and subsystems accumulating 200,000,000 hours of flight operations. Thales Alenia Space in Spain offers a wide range of solutions spanning the design and integration of payloads and subsystems for telecommunications, data transmission and TT&C (tracking, telemetry and command), optical observation instruments, radiofrequency equipment, data processing and digital electronics, network management systems for the ground segment, telemetry transmitters for launchers and communication systems for spaceports.

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NASA technology enables precision landing without a pilot

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)

Following Breadcrumbs

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.

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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.

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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)

Laser Navigation

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.

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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.

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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)

Computer Powerhouse

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.”

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Thales Alenia Space to provide key technology to HERA, ESA’s planetary defence mission

Thales Alenia Space to provide key technology to HERA ESAs

(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.

(courtesy: ESA)

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.

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(courtesy: ESA)

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.

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Observations with the Herschel Space Observatory reveal the composition of the largest Uranian moons

Observations with the Herschel Space Observatory reveal the composition of

(14 September 2020 – Max Planck Institute for Astronomy) More than 230 years ago astronomer William Herschel discovered the planet Uranus and two of its moons. Using the Herschel Space Observatory, a group of astronomers led by Örs H. Detre of the Max Planck Institute for Astronomy now has succeeded in determining physical properties of the five main moons of Uranus.

The measured infrared radiation, which is generated by the Sun heating their surfaces, suggests that these moons resemble dwarf planets like Pluto. The team developed a new analysis technique that extracted the faint signals from the moons next to Uranus, which is more than a thousand times brighter. The study was published today in the journal Astronomy & Astrophysics.

The images show the position of the five largest Uranian moons and their orbits around Uranus on 12 July 2011 as seen by Herschel. Left: Calculated positions and orbits of the moons. The left side of the orbital plane is pointing towards us. The size of the objects is not shown to scale. Right: False-colour map of the infrared brightness at a wavelength of 70 µm after removal of the signal from the planet Uranus, measured with the PACS instrument of the Herschel Space Observatory. The characteristic shape of the signals, which resembles a three-leaf clover, is an artifact generated by the telescope. (courtesy: T. Müller (HdA)/Ö. H. Detre et al./MPIA)

To explore the outer regions of the Solar System, space probes such as Voyager 1 and 2, Cassini-Huygens and New Horizons were sent on long expeditions. Now a German-Hungarian research group, led by Örs H. Detre of the Max Planck Institute for Astronomy (MPIA) in Heidelberg, shows that with the appropriate technology and ingenuity, interesting results can also be achieved with observations from far away.

The scientists used data from the Herschel Space Observatory, which was deployed between 2009 and 2013 and in whose development and operation MPIA was also significantly involved. Compared to its predecessors that covered a similar spectral range, the observations of this telescope were significantly sharper. It was named after the astronomer William Herschel, who found infrared radiation in 1800. A few years earlier, he also discovered the planet Uranus and two of its moons (Titania and Oberon), which now have been explored in greater detail along with three other moons (Miranda, Ariel and Umbriel).

The discovery of the moons in the Herschel data was a coincidence

“Actually, we carried out the observations to measure the influence of very bright infrared sources such as Uranus on the camera detector,” explains co-author Ulrich Klaas, who headed the working group of the PACS camera of the Herschel Space Observatory at MPIA with which the images were taken. “We discovered the moons only by chance as additional nodes in the planet’s extremely bright signal.” The PACS camera, which was developed under the leadership of the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, was sensitive to wavelengths between 70 and 160 µm. This is more than a hundred times greater than the wavelength of visible light. As a result, the images from the similarly sized Hubble Space Telescope are about a hundred times sharper.

Cold objects radiate very brightly in this spectral range, such as Uranus and its five main moons, which – warmed by the Sun – reach temperatures between about 60 and 80 K (–213 to –193 °C).

“The timing of the observation was also a stroke of luck,” explains Thomas Müller from MPE. The rotational axis of Uranus, and thus also the orbital plane of the moons, is unusually inclined towards their orbit around the Sun. While Uranus orbits the Sun for several decades, it is mainly either the northern or the southern hemisphere that is illuminated by the Sun. “During the observations, however, the position was so favourable that the equatorial regions benefited from the solar irradiation. This enabled us to measure how well the heat is retained in a surface as it moves to the night side due to the rotation of the moon. This taught us a lot about the nature of the material,” explains Müller, who calculated the models for this study. From this he derived thermal and physical properties of the moons.

When the space probe Voyager 2 passed Uranus in 1986, the constellation was much less favourable. The scientific instruments could only capture the south pole regions of Uranus and the moons.

The moons resemble the dwarf planets at the edge of the Solar System

Müller found that these surfaces store heat unexpectedly well and cool down comparatively slowly. Astronomers know this behaviour from compact objects with a rough, icy surface. That is why the scientists assume that these moons are celestial bodies similar to the dwarf planets at the edge of the Solar System, such as Pluto or Haumea. Independent studies of some of the outer, irregular Uranian moons, which are also based on observations with PACS/Herschel, indicate that they have different thermal properties. These moons show characteristics of the smaller and loosely bound Transneptunian Objects, which are located in a zone beyond the planet Neptune. “This would also fit with the speculations about the origin of the irregular moons,” adds Müller. “Because of their chaotic orbits, it is assumed that they were captured by the Uranian system only at a later date.”

However, the five main moons were almost overlooked. In particular, very bright objects such as Uranus generate strong artifacts in the PACS/Herschel data, which cause some of the infrared light in the images to be distributed over large areas. This is hardly noticeable when observing faint celestial objects. With Uranus, however, it is even more pronounced. “The moons, which are between 500 and 7400 times fainter, are at such a small distance from Uranus that they merge with the similarly bright artifacts. Only the brightest moons, Titania and Oberon, stand out a little from the surrounding glare,” co-author Gábor Marton from Konkoly Observatory in Budapest describes the challenge.

Sophisticated data processing makes the initially invisible visible

This accidental discovery spurred Örs H. Detre to make the moons more visible so that their brightness could be reliably measured. “In similar cases, such as the search for exoplanets, we use coronagraphs to mask their bright central star,” Detre explains. “Herschel did not have such a device. Instead, we took advantage of the outstanding photometric stability of the PACS instrument.” Based on this stability and after calculating the exact positions of the moons at the time of the observations, he developed a method that allowed him to remove Uranus from the data. “We were all surprised when four moons clearly appeared on the images, and we could even detect Miranda, the smallest and innermost of the five largest Uranian moons,” Detre concludes.

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These images explain how the Uranian moons were extracted from the data. Left: The original image contains the infrared signals from Uranus and its five main moons, measured at a wavelength of 70 µm. Uranus is several thousand times brighter than a single moon. Its image is dominated by artifacts due to interference from the telescope and the camera. Titania and Oberon are barely visible. Center: Using these data, a sophisticated procedure created a model for the brightness distribution of Uranus alone. This is subtracted from the original image. Right: Finally, the signals of the moons remain after the subtraction. At the location of Uranus the not quite perfect extraction method slightly affects the result. (courtesy: Ö. H. Detre et al./MPIA)

“The result demonstrates that we don’t always need elaborate planetary space missions to gain new insights into the Solar System,“ co-author Hendrik Linz from MPIA points out. “In addition, the new algorithm could be applied to further observations which have been collected in large numbers in the electronic data archive of the European Space Agency ESA. Who knows what surprise is still waiting for us there?”

Publication

Ö. H. Detre, T. G. Müller, U. Klaas, et al.
Herschel-PACS photometry of the five major moons of Uranus
Astronomy & Astrophysics, 641, A76 (2020)

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