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(20 August 2020 – NASA) NASA just validated a new type of propellant, or fuel, for spacecraft of all sizes. Instead of toxic hydrazine, space missions can use a less toxic, “green” propellant and the compatible technologies designed to go along with it.

In a little over a year since launch, NASA’s Green Propellant Infusion Mission (GPIM) successfully proved a never-before-used propellant and propulsion system work as intended, demonstrating both are practical options for future missions.

GPIM set out to test a monopropellant – a chemical propellant that can burn by itself without a separate oxidizer – called Advanced Spacecraft Energetic Non-Toxic (ASCENT). Formerly known as AF-M315E, the U.S. Air Force Research Laboratory invented the propellant at Edwards Air Force Base in California. It is an alternative to the monopropellant hydrazine.

An Aerojet Rocketdyne researcher examines a container of the Advanced Spacecraft Energetic Non-Toxic (ASCENT) monopropellant during preparation for flight testing. (courtesy: Aerojet)

“This is the first time in 50 years NASA tested a new, high-performing monopropellant in space,” said Tim Smith, GPIM mission manager at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “It has the potential to supplement or even replace hydrazine, which spacecraft have used since the 1960s.” Based at Marshall, NASA’s Technology Demonstration Mission (TDM) program manages the mission.

GPIM’s effective demonstration of the propellant paved the way for NASA’s acceptance of ASCENT in new missions. The next NASA mission to use ASCENT will be Lunar Flashlight. The small spacecraft, which aims to provide clear-cut information about the presence of water deposits inside craters, will launch as a secondary payload on Artemis I, the first integrated flight test of NASA’s Orion spacecraft and Space Launch System (SLS) rocket.

Despite being pink in color, ASCENT is considered “green” for its significantly reduced toxicity compared to hydrazine, which requires protective suits and rigorous propellant loading processing procedures. It is safer to store and use, requiring minimal personal protective equipment such as lab coats, goggles, and gloves. Besides being easier and less expensive to handle here on Earth, when loading a spacecraft with propellant, for example, ASCENT will allow spacecraft to travel farther or operate longer with less propellant in their tank, given its higher performance.

But to test the propellant on a small spacecraft, the GPIM team had to develop hardware and systems compatible with the liquid. Aerojet Rocketdyne of Redmond, Washington, designed and built the five thrusters onboard GPIM. Aerojet Rocketdyne and Ball Aerospace of Boulder, Colorado, co-designed the other elements of the propulsion system.

While in orbit, GPIM tested the propellant and propulsion system, including the thrusters, tanks, and valves, by conducting a planned series of orbital maneuvers. Attitude control maneuvers, the process of maintaining stable control of a satellite, and orbit lowering demonstrated the propellant’s pre-mission projected performance, showing a 50% increase in gas mileage for the spacecraft compared to hydrazine.

With the technology demonstration objectives almost complete, the mission proved ASCENT and the compatible propulsion system are a viable, effective alternative for NASA and the commercial spaceflight industry, Smith said.

“We can attribute GPIM’s success to a strong partnership,” Smith added. NASA’s Space Technology Mission Directorate selected Ball Aerospace to lead the mission in 2012. In addition to building the mini-refrigerator-sized spacecraft, the company integrated and tested the payloads and propulsion system before launch and provides flight operations support.

“We are excited to announce flight operations have been very smooth, with the new propulsion subsystem operating as we anticipated,” said Christopher McLean, GPIM principal investigator for Ball Aerospace. “We greatly appreciate the partnership and continuous support throughout this mission from NASA’s Space Technology Mission Directorate, and program management office at Marshall.”

GPIM approaches mission completion, and the spacecraft has started a series of deorbit burns. Approximately seven burns will lower the orbit to about 110 miles (180 kilometers) and deplete the propellant tank. The small spacecraft will burn up in Earth’s atmosphere upon reentry, anticipated in late September 2020.

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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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