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(18 September 2020 – Naval Research Laboratory) Two U.S. Naval Research Laboratory Space Science Division (SSD) researchers joined an international cadre of scientists July 27 in presenting the results of the first simultaneous global solar corona images of the helium and hydrogen emission that is helping scientists to better understand the space environment.

The paper, “Global Helium Abundance Measurements in the Solar Corona,” was published online in Nature Astronomy and discusses the abundance of helium relative to hydrogen in the solar corona, the outer atmosphere of the sun, seen from earth only during eclipses.

NRL Astrophysicist Dennis Wang, Ph.D., software lead for the HElium Resonance Scattering in the Corona and HEliosphere (HERSCHEL) rocket flight, was responsible for flight and ground software. His NRL colleague, Research Physicist Martin Laming, Ph.D., managed the new model of element abundance fractionation, to include helium.

A composite image of the Sun showing the hydrogen (left) and helium (center and right) in the low corona. The helium at depletion near the equatorial regions is evident. (courtesy: NASA)

“Understanding space weather is important for space situational awareness, that is, forecasting and mitigating the effects of solar activity on Navy and Defense Department satellites,” said Laming. “This was one case where instead of explaining the observations after the fact, I was able to see a prediction I had made come true.”

The HERSCHEL sounding rocket, launched Sep. 14, 2009, provided a number of technological advances in space-based remote sensing. Using a concept developed at NRL for a coronagraph functioning in the extreme ultraviolet regime of the electromagnetic spectrum, the helium coronagraph obtained the first images of the solar atmosphere in the region of the solar wind source surface from light resonantly scattered from helium ions.

The leading model for solar wind variability used by the Department of Defense and National Oceanic and Atmospheric Administration space weather forecasters is an NRL SSD product, known as the Wang, Sheely, Arge Model which is based on simple assumptions about the relation of the solar magnetic field structure and the solar wind, and is reasonably successful in predicting the overall variability of the solar wind as it reaches Earth.

Geomagnetic storms impact radio frequency transmission at frequencies refracted, or reflected, by the ionosphere. The Navy uses magnetic sensors in various battlespace applications, which could be disrupted during large geomagnetic storms and Coronal Mass Ejections. These are major reasons why the Navy is interested in disruptions of the Earth’s magnetic field structure in these measurements.

“There is a long chain of work efforts that go from fundamental understanding of the solar atmosphere, to specifying the observables that need to be monitored before we eventually get to reliable Space Weather forecasts,” said Laming. “In the future, service members should anticipate more reliable satellite-based Command, Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance.”

Laming demonstrates a strong belief in his model’s prediction capability and his understanding of the sun’s corona adding, “I think we all have more confidence in my model and the conclusions one might draw from it.”

About the U.S. Naval Research Laboratory

NRL is a scientific and engineering command dedicated to research that drives innovative advances for the Navy and Marine Corps from the seafloor to space and in the information domain. NRL headquarters is located in Washington, D.C., with major field sites in Stennis Space Center, Mississippi; Key West, Florida; and Monterey, California, and employs approximately 2,500 civilian scientists, engineers and support personnel.

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ViaLite provides SES with cross-border solution

ViaLite provides SES with cross border solution

(27 November 2020 – ViaLite) Radio frequency over fiber optic links are a great solution for moving high frequency analog signals over a long distance, but solutions need expert planning, design and installation to get the best performance.

When SES needed a long distance link from the European Space Agency Redu station in Belgium to the SES site in Luxembourg, ViaLite’s experience in the market and long distance link solutions made the company a winning choice for the project.

SES, a World Teleport Association (WTA) leading satellite operator, required a long distance link system which provided a high dynamic range in bandwidth and could be controlled remotely by SES operations staff. The distance between the SES site and the Redu station is over 120 km and crosses over the border between Belgium and Luxembourg.

ViaLite’s DWDM long distance link system was the chosen solution; installed at the two sites, with a third site at the border required for signal amplification and interconnect between the two countries. The technology used is capable of connecting sites that can be hundreds of kilometers apart and has full bandwidth capability from 700 MHz through to 2450 MHz. As part of the system, optical amplifiers, optical switches, multiplexers and de-multiplexers were supplied, as well as dispersion compensation module and delay lines; provided to help with optimizing and balancing.

SES’s teleport (courtesy: SES)

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ViaLite long distance link system (courtesy: ViaLite)

Steve Jones, a Senior Systems Engineer at SES, commented on the results: “We are over the moon, we couldn’t ask for more. ViaLite were extremely supportive and most importantly, it works!”

Amair Khan, from ViaLite, said: “It was a great project to work on. It’s rare to have the opportunity to deploy a fiber link across country borders. The solution we provided was adaptable in order to compensate for optical losses throughout the fiber system.”

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Supercapacitors ready to deliver maximum power to space

Supercapacitors ready to deliver maximum power to space

(27 November 2020 – ESA) High-power supercapacitors – already found within terrestrial electric cars, trains, lifts and cranes – are on their way to space.

An ESA-led project with Airbus Defence and Space developed and tested a supercapacitor design able to provide brief bursts of very high power levels to space missions as required. Potential uses might include operation of high-power satellite radar systems, to stabilise overall onboard power during solar eclipses or other such events or launcher thrust vectoring.

Bank of supercapacitors engineering model (courtesy: ESA/Airbus Defence and Space)

“While traditional batteries store electric energy on a chemistry basis, supercapacitors do so on the basis of physics. The energy is stored as electrostatic charge, within an electrochemical double layer at the boundary between an organic electrolyte and activated carbon layers,” explains energy storage engineer Brandon of ESA’s Energy Storage section.

“This means they can both store and discharge power at a very fast rate that batteries cannot match, for many thousands of cycles with almost no internal resistance. However they have the corresponding disadvantage that they possess a lower overall energy density, so are able to store only a fraction the amount of energy of a battery with the same mass.”

Supercapacitors are, for instance, often used within electric and hybrid cars, storing the electric energy generated by braking wheels for later reuse and supplying power boosts for rapid acceleration.

“We performed an initial study of such a ‘Bank of Supercapacitors’ unit through ESA’s Advanced Research in Telecommunications Systems, ARTES, programme,” adds Brandon. “We studied possible applications and which commercial cells could be feasible for the application in space. The results of this study were very promising.

“Then Airbus Defence and Space in France approached us, wanting to finalise and qualify such a design for space. This project proceeded on a co-funded basis through our General Support Technology Programme – preparing promising products for space and the marketplace.”

The first challenge was to design and construct a working prototype ‘Bank of Supercapacitors’ (BOSC), based on 34 supercapacitors in series with three strings in parallel, incorporating thermal sensors to keep it from overheating and degrading.

“To make these prototype BOSCs suitable for space required careful ‘potting’ – meaning the insertion of epoxy between the stacked supercapacitors, connectors and printed circuit boards,” adds Brandon.

“This sealant potting is needed for multiple reasons, firstly to help safeguard these delicate devices from the violent vibration of launch. It also prevents the unwanted interaction of bare wires and to minimise ‘outgassing’ of electrolyte from the supercapacitor can – the release of unwanted gases in the vacuum of space.”

BD Sensors in the Czech Republic– in charge of designing and manufacturing the BOSC – was responsible for developing this critical process.

Mechanical testing – coming down to violent, launcher-strength shaking, as well as exposure to space-quality vacuum and temperature extremes – took place at project partner EGGO Space in the Czech Republic. Radiation testing was also essential, involving kilorads of exposure, to check the bank would go on operating when exposed to the same kind of charged particles experienced in orbit.

Gabriel Beulaguet of Airbus Defence and Space, engineering and project manager for the project, comments: “we have set-up in our laboratory a long life test under relevant electrical, thermal and vacuum conditions. After more than 2.3 million cycles, the performances – especially in terms of fading and balancing – are behaving as expected and the test will continue to run”.

Testing the electrical performance of the BOSC involved millions of charge and discharge cycles, including a dedicated lifetime test campaign to look at ageing effects. In parallel, the BOSC was also subjected to ‘abuse’ testing – involving short circuits, overcharges and physical shock from impacts.

“We found the bank can take a huge amount of current, up to 400 amps, several times without damage,” adds Brandon.

Denis Lacombe of ESA’s Technical Reliability and Quality Division, technical officer for the project, explains: “Now that lifetime testing is about to conclude, after three years of hard work we have a space-qualified product, ready for use by Airbus and added to the European Preferred Parts List so other missions can make use of it as well, enabling high-power space applications of all kinds.”

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Northrop Grumman names Scott Stapp as Chief Technology Officer

Northrop Grumman names Scott Stapp as Chief Technology Officer

(25 November 2020 – Northrop Grumman) Northrop Grumman Corporation has named Scott Stapp chief technology officer (CTO).

Stapp will report to Kathy Warden, chairman, chief executive officer and president and will work closely with the executive leadership team.

Scott Stapp, Chief Technology Officer (courtesy: Northrop Grumman)

As CTO, Stapp will lead the company’s technology strategy. He will help to ensure the company continues to leverage current technology and identify new solutions to bring to customers, creating new business opportunities and strengthening the company’s position on existing programs. He will also play a key role in engaging and developing the company’s technical talent.

Previously, Stapp was vice president, resiliency and rapid prototyping, with Space Systems, leading the sector’s rapid prototyping and resiliency programs across critical space missions. Prior to this, he served as vice president, applied research and technology development, with Aeronautics Systems.

Before joining Northrop Grumman in 2014, Stapp led the governance, acquisition and oversight of all DoD special access programs, for the Office of the Secretary of Defense, and served as the principal staff assistant to the undersecretary of defense, acquisition, technology and logistics.

Stapp holds a bachelor’s degree in electrical engineering from the University of Wyoming, a master’s degree in electrical engineering from the University of New Mexico and a master’s degree in national resource management from the Industrial College of the Armed Forces.

Northrop Grumman solves the toughest problems in space, aeronautics, defense and cyberspace to meet the ever evolving needs of our customers worldwide. Our 90,000 employees define possible every day using science, technology and engineering to create and deliver advanced systems, products and services.

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