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(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.

observations 2

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?”


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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Masten Space Systems awarded two NASA Tipping Point contracts

Masten Space Systems awarded two NASA Tipping Point contracts

(21 October 2020 – Masten Space Systems) NASA and Masten Space Systems announced that the Space Technology Mission Directorate has chosen Masten for two Tipping Point awards as part of the agency’s Artemis mission to return to the Moon.

The first award is for Masten’s Metal Oxidation Warming System (MOWS) which is being developed in partnership with Penn State as a chemical heating solution to help spacecraft survive in sunlight-deprived lunar environments. The second award will drive completion of Masten’s state-of-the-art aerospace testbed, named Xogdor, to provide the industry an updated flight test analog for critical Artemis technologies.

Masten’s XL-1 lunar lander will deliver NASA and commercial payloads to the Moon’s southern pole by December 2022. (coutesy: Masten Space Systems)

“We are excited to see such an auspicious group of Tipping Point awards this year,” said Masten CEO Sean Mahoney. “It’s an honor to be in such great company with all these amazing awards as NASA’s forward-looking Space Technology Mission Directorate steps up to fund the private companies who are producing out-of-the-box innovations that will take America back to the Moon, to stay.”

In partnership with Penn State, Masten will mature MOWS, a lunar warming solution with electricity cogeneration that allows spacecraft systems to survive the lunar night and operate in shadowed lunar regions. MOWS employs moderate-temperature chemical reactions for thermal control with order-of-magnitude greater specific energy than battery-based approaches. MOWS is useful for both robotic and manned missions, as both require thermal control for extended surface operations.

“MOWS technology benefits both NASA and commercial missions as it significantly expands the scope of lunar exploration missions,” said Matthew Kuhns, chief engineer at Masten. “The ability to survive the lunar night extends mission durations beyond the current capability of around 14 days, allowing missions at least six weeks, two lunar days and one lunar night, and possibly longer, greatly increasing our capacity to perform more science, operate customer payloads, and reduce risk for future Artemis missions on the Moon.”

Masten will mature its Xogdor flight vehicle to operational service to provide an updated system for testing aerospace technologies in a relevant flight environment. Over this three year project, Masten will complete the development and flight testing of a Xogdor vehicle. The defined effort will support risk reduction of technologies through flight testing in pursuit of NASA’s Moon-to-Mars campaign with a focus on building an EDL (Entry, Descent, Landing) test capability for near-term lunar missions. Xogdor will be the sixth vehicle in Masten’s line of reusable rockets, which have had more than 600 successful VTVL (Vertical Takeoff Vertical Landing) flights over 15 years of heritage.

“Xogdor is poised to become the industry’s state-of-the-art testing analog with performance capabilities far exceeding those of currently available EDL testbeds,” said Masten CTO, Dave Masten. “Through this Masten-NASA partnership, Xogdor will be available to test critical Artemis technologies, including hazard detection instruments, precision landing avionics, innovative flight software, Plume Surface Interaction (PSI) experiments, and other critical EDL experiments as early as 2023.”

“P3 is proud to be supporting Masten with Champ Turbopumps for the Xogdor rocket for this important NASA Tipping Point program,” said Phil Pelfrey, president of P3 Technologies.

“This is the most Tipping Point proposals NASA has selected at once and by far the largest collective award value,” said NASA’s Associate Administrator for Space Technology Jim Reuter. “We are excited to see our investments and collaborative partnerships bring about new technologies for the Moon and beyond while also benefiting the commercial sector.”

About Masten Space Systems

Mojave, California-based Masten Space Systems wrangles rocket powered landing from sci-fi into reality, connecting the steps from napkin, to lab, to test site, and all the way to the surface of the Moon. For over 15 years the Masten team has torn down barriers to space, working with partners of all types to create value in the space ecosystem. Masten is the partner of choice for fellow innovators, and explorers who are changing how we access and use space, bringing the benefits of space to the benefit of humans here on Earth.

About NASA STMD’s Tipping Point Program

Through the “Tipping Point” solicitation, NASA seeks industry-developed space technologies that can foster the development of commercial space capabilities and benefit future NASA missions. A technology is considered at a tipping point if an investment in a demonstration will significantly mature the technology, increase the likelihood of infusion into a commercial space application, and bring the technology to market for both government and commercial applications. The public-private partnerships established through Tipping Point selections combine NASA resources with an industry contribution of at least 25% of the program costs, shepherding the development of critical space technologies while also saving the agency, and American taxpayers, money.

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Cobham Advanced Electronic Solutions launches industry’s highest density NAND flash memory module for space applications

Cobham Advanced Electronic Solutions launches industrys highest density NAND flash

(21 October 2020 – Cobham) Cobham Advanced Electronic Solutions (CAES) today announced the industry’s highest density NAND flash memory device for a range of demanding space applications.

The 4 terabit (Tb) triple-level cell (TLC), NAND Flash Memory Module delivers 32 times the density of the closest competing device while fitting into the same industry-standard 12mm x 18mm plastic-encapsulated microcircuit (PEM) package. With access to unparalleled storage capacity, designers can significantly increase sensor and digital signal processing in applications such as solid-state drives and recorders, reconfigurable computing systems, imaging and communications data buffering applications.

New CAES UT81NDQ512G8T delivers highest density NAND flash memory module for space applications (courtesy: Cobham)

“Our 4Tb NAND Flash Memory Module delivers an order of magnitude boost in memory density at lower power and without any increase in package size,” said Kevin Jackson, vice president, space systems, Cobham Advanced Electronic Solutions. “This directly improves the performance and capability of spacecraft instruments, for example, by increasing the signal fidelity and resolution of satellite imaging equipment. At the same time, our tightly-controlled supply chain and extensive testing processes mean that designers no longer have to up-screen commercial flash memory solutions in the hope of finding radiation-tolerant components.”

The new module performs up to 667 mega-transfers per second (MT/s) and is compliant with both Open NAND Flash Interface (ONFI) 4.0 and JEDEC NAND Flash Interoperability (JESD230C) specifications. While aerospace designers must screen commercial-grade NAND flash to estimate radiation tolerance and operational lifetime, the new CAES radiation-assured flash modules undergo extensive pre-testing. This includes Total Ionizing Dose (TID) and Single-Event Effects (SEE) characterization on a wafer lot-by-lot basis to ensure optimum radiation hardness. To maximize quality control across its manufacturing supply chain, CAES also applies Parts, Materials and Process (PMaP) failure-mode analysis to monitor for potential variations in the semiconductor fabrication process.

The UT81NDQ512G8T, 4Tb NAND flash module supports NV-DDR3 I/O (667 MT/s), NV-DDR2 I/O (533 MT/s), asynchronous I/O (50 MT/s) speeds and TLC endurance of 3,000 program/erase cycles. The module operates across +2.7 – +3.6V input and +1.14 – +1.26V or +1.7 – +1.95V output voltage ranges and specified to a temperature range of -40°C to +85°C. The 132-ball BGA module is available now in engineering units, with flight models to be released in the second quarter of 2021.

CAES also provides other technologies for commercial, civil, military, and other government spacecraft. With a space pedigree spanning nearly 40 years, CAES offers a full range of solutions for the world’s leading launch vehicles, satellites and space exploration missions. Key capabilities include radiation hardened and high reliability microelectronics, application specific integrated circuits (ASIC), electronic manufacturing services, motion control and positioning, antennas and apertures, radiation effects testing, RF, microwave and millimeter wave microelectronics, motion control devices, power solutions, intellectual property cores, avionic solutions and LEON/SPARC processors.

About Cobham Advanced Electronic Solutions

Cobham Advanced Electronic Solutions is the largest provider of analog and radiation hardened technology for the United States aerospace and defense industry. With a broad portfolio of off-the-shelf and customized RF, microwave and high reliability microelectronic products and subsystems, CAES offers a complete range of solutions for the entire signal chain from aperture to digital conversion.

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Ovzon introduces Ovzon T6, a new portable satellite terminal

Ovzon introduces Ovzon T6 a new portable satellite terminal

(23 October 2020 – Ovzon) The new Ovzon T6 terminal is based on Ovzon’s satellite terminal expertise and includes new ground-breaking antenna technology, featuring automatic polarization adjustment.

The terminal is lighter and smaller than the present industry standard, Ovzon T5, thus pushing mobility further.

Ovzon’s T6 terminal (courtesy: Ovzon)

With 50 Mbps transmit and receive capabilities in a laptop sized format the new Ovzon T6 is the world smallest and lightest terminal with such performance, with the Ovzon T5 as a close second. The all-in-one rugged design, fully integrated, is compact without sacrificing performance. The weight is only 6 kg and the form factor makes it very easy to hand carry.

The patented Ovzon antenna with its electrical polarization removes the need for third axis mechanical polarization adjustment truly making it is as easy to use as an L-band terminal.

The intuitive graphical interface gives the user complete control through the built-in display or with any smartphone, tablet or laptop.

The terminal, that is IP 67 protected, is designed for use in extreme weather conditions, thus meeting the most demanding user needs.

”The Ovzon T6 is a giant leap forward compared with its successful predecessor, the industry standard Ovzon T5, developed and introduced in 2014. We are excited to bring this new Ovzon T6 terminal to the market as we approach the launch of our own satellite, Ovzon 3, at the end of 2021. New, capable terminals are important to further enhance our coming service and offering on Ovzon 3”, says Magnus René, CEO of Ovzon.

Ovzon is revolutionizing mobile broadband via satellite providing global coverage with the highest bandwidth through the smallest terminals. Founded in 2006, Ovzon develops end-to-end solutions meeting the growing demand of mobile broadband connectivity for customers with high performance requirements.

Ovzon’s combination of advanced proprietary satellite technology and unique ultra-small terminals answers the needs for mobile users to connect anywhere and transmit large amounts of data. Customers include Government, Defense, Media, Maritime, Aviation and NGOs using highly mobile platforms. Our dedicated and experienced team ensures a premium service for our demanding global customers.

The company has offices in Stockholm in Sweden and Bethesda (MD) and Tampa (FL) in the United States. Ovzon is publicly listed on Nasdaq First North Growth Market

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