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(21 August 2020 – USRA) Europa’s outer icy shell has completely reoriented itself in one of the last geologic events recorded on its young surface.

Europa’s poles are not where they used to be. Cracks in the surface of Jupiter’s icy moon indicate its shell of ice rotated by 70 degrees sometime in the last several million years. In addition to supporting prior evidence for the existence of a subsurface ocean, it also means that the geologic history of Europa’s surface must be reexamined.

Perspective views of fractures on the surface of Europa formed during true polar wander. The large cracks crossing the scene from left to upper right are ~3 kilometers (1.9 miles) wide and 200 meters deep. The double ridges crossing the scene are similar in width. (courtesy: P. Schenk/ USRA/LPI)

New research, led by Universities Space Research Association’s Senior Staff Scientist Dr. Paul Schenk at the Lunar and Planetary Institute (LPI), confirms that Europa’s large global scale circular patterns formed during a large reorientation of the its icy outer shell with respect to its spin axis, a process known as true polar wander. This can only happen if the icy shell is uncoupled, or floating free, separated from the rocky core of the planet by a liquid water ocean. The findings were published July 29, 2020 in Geophysical Research Letters.

“Our key finding is that the fractures associated with true polar wander on Europa cross-cut all terrains. This means that the true polar wander event is very young and that the ice shell and all features formed on it have moved more than 70° of latitude from where they first formed,” reports Dr. Schenk. “If true, then the entire recorded history of tectonics on Europa should be reevaluated.”

Using a combination of global maps from Galileo and Voyager data with improved precision, and detailed topographic data derived from them, a team of scientists from the LPI in Houston, the University of California at Santa Cruz, and the University of Arizona in Tucson have correlated large fractures on the surface of Europa with previously identified concentric circular depressions on the surface.

NASA’s Galileo spacecraft orbited Jupiter from 1995 to 2003 and returned hundreds of images of Europa’s surface. Reconstruction of the global map of Europa at 200-meter resolution in color in preparation for a return to Europa revealed that these mysterious fracture systems were part of the circular true polar wander patterns identified previously. Topographic mapping in the highest resolution images of the fractures at 40 meters per pixel show that the fractures are more than 200 meters deep. The fractures cut through all known terrains and thus show that the deformation related to the global reorientation (or true polar wander) event was one of the last events to occur on Europa. These features also imply that the floating ice shell on Europa may have thickened over time.

“Another important aspect of this work is that it makes predictions for additional features and ice shell properties which can be tested when the planned Europa Clipper spacecraft starts observing Europa,” says coinvestigator Francis Nimmo at the University of California at Santa Cruz.

“In addition to generating global-scale tectonic features, true polar wander also produces global-scale gravity and shape perturbations, which affects gravity and shape constraints on the interior structure,” says coinvestigator Isamu Matsuyama at the University of Arizona.

These too can be searched for and tested when Europa Clipper arrives later this decade. Europa Clipper will complete the map of Europa, including high-resolution images and soundings of these features. These maps will help determine the absolute age of these fractures and depressions and other consequences of the polar wander event that created them.

Publication

Schenk P., Matsuyama I., and Nimmo F. (2020) A Very Young Age for True Polar Wander on Europa from Related Fracturing. Geophysical research letters, e2020GL088364

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Most advanced SBIRS missile warning satellite ready for 2021 launch

Most advanced SBIRS missile warning satellite ready for 2021 launch

(2 December 2020 – Lockheed Martin) Lockheed Martin today announced the U.S. Space Force has determined the fifth Space Based Infrared System Geosynchronous Earth Orbit satellite (SBIRS GEO-5) is complete and ready for launch in 2021.

Built in a record time and at no additional cost to the government for the upgrade, SBIRS GEO-5 is the first military space satellite built on the company’s modernized, modular LM 2100 combat bus. SBIRS GEO-6, launching in 2022, is also being built on the new bus designed for speed and resilience.

Lockheed Martin’s SBIRS GEO-5 satellite, the first military space satellite built on a modernized LM 2100 combat bus, built in record speed, is ready for a 2021 launch. (courtesy: Lockheed Martin)

“SBIRS’ role as an ever-present, on-orbit guardian against global ballistic missile threats has never been more critical,” said Tom McCormick, Lockheed Martin’s vice president for Overhead Persistent Infrared (OPIR) Systems. “In 2019 alone, SBIRS detected nearly one thousand missile launches, which is about a two-fold increase in two years.”

“Completing the production of a complex missile-warning satellite during the challenging COVID environment is a huge accomplishment and is a testament to Lockheed Martin’s professionalism and dedication to the security of our Nation,” said Capt. Alec Cook, Space and Missile Systems Center’s SBIRS GEO-5/6 Assembly, Test, and Launch Operations lead.

Both SBIRS GEO-5 and GEO-6 are slated to join the U.S. Space Force’s constellation of missile warning satellites, equipped with powerful scanning and staring infrared surveillance sensors, which protect our nation 24-7. These sensors collect data that allow the U.S. military to detect missile launches, support ballistic missile defense, expand technical intelligence gathering and bolster situational awareness on the battlefield.

SBIRS GEO-5 was officially completed on Oct. 29, 2020.

LM 2100 Bus: Focuses on Speed and Resiliency

The LM 2100 bus is the result of a Lockheed Martin internally-funded, multi-year modernization initiative. It is designed to provide greater resiliency and cyber-hardening; enhanced spacecraft power, propulsion and electronics; common components and procedures to streamline manufacturing; and a flexible design that reduces the cost to incorporate future, modernized sensor suites.

“We added even further enhanced resiliency features to the LM 2100 to create an initial ‘combat bus’ for the Space Force. SBIRS GEO-5 has proven itself a valuable incremental step towards achieving the resilient missile warning that will be provided by the Next Gen OPIR Block 0 System, the follow-on to SBIRS,” added McCormick.

In June 2015, the Air Force agreed to rebaseline SBIRS GEO-5 and GEO-6 to upgrade both satellites to Lockheed Martin’s modernized LM 2100 bus at no additional cost. From that point, SBIRS GEO-5 was completed in approximately five years, in line with the government’s need to increase production speed and address emerging threats, and still supporting the government’s original 2021 launch date.

Besides SBIRS GEO-5 and GEO-6, the LM 2100 space vehicle is the baseline for three Next Gen OPIR Block 0 GEO satellites expecting to launch starting in 2025; and the future GPS III Follow On (GPS IIIF) satellites, which are expected to launch starting in 2026.

Lockheed Martin is proud to be part of the SBIRS team led by the Production Corps, Geosynchronous Earth Orbit Division, at the U.S. Space Force’s Space and Missile Systems Center, Los Angeles Air Force Base, California. Lockheed Martin Space, Sunnyvale, California, is the SBIRS prime contractor, with Northrop Grumman Aerospace Systems, Azusa, California, as the payload integrator.

About Lockheed Martin

Headquartered in Bethesda, Maryland, Lockheed Martin is a global security and aerospace company that employs approximately 110,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services.

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EM Solutions secures second L3Harris order

EM Solutions secures second L3Harris order

(3 December 2020 – EM Solutions) EM Solutions has recently received a second order to supply its Ka-band transceivers for the L3Harris Technologies Panther II Very Small Aperture Terminals (VSAT).

The new contract, valued at more than $US2M, will deliver over 100 Ka-band transceivers to L3Harris across the first half of 2021.

Ka band transceiver (courtesy: EM Solutions)

EM Solutions CEO Dr Rowan Gilmore, said “We are delighted to have been chosen as the exclusive provider of our latest broadband Ka-band transceivers into the new Panther II program. These transceivers build further upon our core technology that has been supplied over recent years into numerous maritime, airborne and land mobile systems. Based on the latest GaN technology, they cover both the military Ka-band spectrum and commercial Ka-band as well.”

Jerry Adams, general manager of VSAT for L3Harris, said “L3Harris and EM Solutions have been working for several years to perfect a transceiver that had the right size and weight for the Panther II terminal, yet was powerful enough to meet the tough WGS satellite certifications. The new transceiver fits the bill perfectly.”

Adams continued “We are pleased that our collaboration with EM Solutions has yielded such great results, so that our Panther II manpack terminal will remain at the forefront of military satellite communications, globally. The Panther II terminal is the smallest physical terminal in use by the Marines. It can be carried as a manpack and set up by an individual within 10 minutes.”

The contract award to EM Solutions follows an earlier order to supply 50 transceivers that are already being delivered to L3Harris.

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Contract signed for new Copernicus ROSE-L mission

Contract signed for new Copernicus ROSE L mission

(3 December 2020 – ESA) ESA and Thales Alenia Space have today signed a contract to develop the new high-priority Copernicus Radar Observation System for Europe in L-band (ROSE-L) environmental monitoring mission – as part of Europe’s Copernicus programme.

The contract was signed in the presence of Riccardo Fraccaro, Undersecretary of the Italian Prime Minister’s Office, and ESA’s Director General, Jan Wörner.

With launch planned in 2028, ROSE-L will provide continuous day-and-night all-weather monitoring of Earth’s land, oceans and ice, and offer frequent images at a high spatial resolution.

During its 7.5-year lifetime, the ROSE-L mission will realise new information that cannot be gathered by existing satellites or through other means. ROSE-L will deliver essential information on forests and land cover, leading to improved monitoring of the terrestrial carbon cycle and carbon accounting.

The mission will also greatly extend our ability to monitor minute surface displacements and helping detect geohazards. It will automatically map surface soil moisture conditions and monitor sea and land ice, greatly helping climate change research and mitigation.

Radar Observation System for Europe in L-band (ROSE-L) (courtesy: Thales Alenia Space)

From its 690 km polar orbit, ROSE-L will carry an active phased array synthetic aperture radar instrument. The radar antenna will be the largest planar antenna ever built measuring an impressive 11 metres by 3.6 metres – roughly the size of 10 ping-pong tables.

With a contract secured worth €482 million, Thales Alenia Space in Italy is the prime contractor for the mission, with Airbus Defence and Space in Germany responsible for the radar instrument. The industrial team includes 29 companies (including 15 SME’s) from 15 countries.

ESA’s Director of Earth Observation Programmes, Josef Aschbacher, said, “I am extremely glad to sign the ROSE-L contract today. ROSE-L will not only complement the radar capabilities of the current Copernicus Sentinel-1 mission, but will also provide a new set of measurements of vegetation, ice and ocean parameters. It will be a key satellite mission to better understand climate change and simulate its impact on humankind.”

The European Commission’s Director-General for Defence Industry and Space, Timo Pesonen, commented, “We are happy to see the signature of the ROSE-L contract today. Its features are expected to respond to several needs we have identified in particular in land management and in ocean monitoring. We look forward to welcoming ROSE-L in the Copernicus Constellation.”

The contract for ROSE-L is the last of the six new high-priority candidate missions to be signed. The six Copernicus high-priority Sentinel Expansion missions are planned to complement the current capabilities of the Sentinels and address EU policy priorities and gaps in Copernicus user needs.

The European Copernicus flagship programme provides Earth observation and in situ data, as well as a broad range of services for environmental monitoring and protection, climate monitoring and natural disaster assessment to improve the quality of life of European citizens.

Copernicus is the biggest provider of Earth observation data in the world – and while the EU is at the helm of this environmental monitoring programme, ESA develops, builds and launches the dedicated satellites. It also operates some of the missions and ensures the availability of data from third party missions.

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