Nanowerk November 8, 2022 Ultra-thin solar cells’ radiation tolerance may allow them to be used in harsh radiation environments, where thicker cells would degrade rapidly. Researchers in the UK irradiated devices with an 80 nm GaAs absorber layer with 3 MeV protons. They mapped the introduction of radiation-induced defects with increasing proton fluence and characterized a decrease in carrier lifetime after irradiation fluence. Despite the substantial reduction in carrier lifetime, short-circuit current did not degrade up to a proton fluence of 1 × 1015 cm−2, beyond which the short-circuit current collapsed. The exposure correlated with the point at which the carrier lifetime became comparable to […]
Tag Archives: Satellite technology
Russia launches classified military satellite
Phys.org November 25, 2021 According to the Russian defense ministry, a Soyuz rocket carrying a classified payload blasted off from the Plesetsk cosmodrome in northern Russia in the early hours of Thursday morning. It is believed to be part of the Kremlin’s early warning anti-missile system. It did not provide further details. According to the Spaceflightnow website, which covers space launches, the launch could be delivering a Tundra satellite. Russia has previously launched Tundra satellites in 2015, 2017 and 2019, according to Interfax…read more.
Breakthrough material can protect satellites from ultraviolet radiation and atomic oxygen in low-Earth orbit
Phys.org February 16, 2021 Atomic oxygen is created when O2 molecules break apart, a process made easier in space because of the abundance of ultraviolet radiation affecting the structural integrity of space structures. An international team of researchers (UK, Germany) has developed a nano-barrier that bonds to the surface of polymer or composite materials, protecting them from erosion in low-Earth orbit without disrupting the functional performance of the space structure. The multilayered protection barrier deposited via a custom-built plasma-enhanced chemical vapor deposition system is designed to deposit all necessary layers without breaking vacuum to maximize the adhesion to the surface […]
Researchers create origami-inspired satellite antennas that can self-fold
TechXplore February 4, 2021 Satellites and space vehicles will need to pack more cargo for the long haul. However, certain items, like dish antennas used for wireless communication, pose a challenge since they cannot be very densely packed for flight because of their signature bowl shape. A team of researchers in the US (Texas A&M University, Pennsylvania State University, UC Irvine) has designed, fabricated, and characterized a self-foldable Active Origami Reflector Antenna (AORA) of parabolic form. They used shape memory polymer (SMP) composites and applied origami principles for smooth folds to determine the shape and fold pattern of a planar […]
Building an Orbiting Internet Just for Satellites
IEEE Spectrum January 23, 2020 Small satellites in the low earth orbit depend on NASA’s Tracking and Data Relay Satellite System (TDRSS) to route signals from satellites to the correct ground stations when the satellite is on the other side of the earth. TDRSS is rarely accessible to companies, prohibitively expensive to use, and over 25 years old. To alleviate these problem a company in the US is creating a commercial replacement for TDRSS by building a constellation of many tiny satellites in LEO. The satellites will form the backbone of a space-based mesh network operating much like an Internet […]
Satellite constellations harvest energy for near-total global coverage
Science Daily January 10, 2020 A team of researchers in the US (Industry, UC Davis, Cornell University) has discovered two alternative 4-satellite constellations with 24- and 48-hour periods, both of which attain nearly continuous global coverage. They harness energy from nonlinear orbital perturbation forces (e.g., Earth’s geopotential, gravitational effects of the sun and moon, and solar radiation pressure) to reduce their propellant and maintenance costs. The 24-hour period constellation reduces the overall required vehicle mass budget for propellant by approximately 60% compared to a geostationary Earth orbit constellation with similar coverage over typical satellite lifetimes. The discovery could drive advances […]
U.S. military tests radiation belt cleanup in space
Science Magazine January 3, 2020 High-energy electrons, shed by radioactive debris and trapped by Earth’s magnetic field, are fritzing out the satellites’ electronics and solar panels. Now, defense scientists are trying to devise a cure. Three space experiments—one now in orbit and two being readied for launch in 2021—aim to gather data on how to drain high-energy electrons trapped by Earth’s magnetic field in radiation belts encircling the planet…read more. Related article
New Spot-Beam Antennas Boost Communication Satellites’ Bandwidth
IEEE Spectrum September 28, 2018 A company based in the US has built massive communications satellites. The spot beams produced by antennas onboard focus in slightly different directions, allowing the same spectrum bands to be used multiple times without interference. Spot beams ultimately function similarly to cell towers. Eventually, the 18V and 19V will look down on Earth with their spot beams and wide beams. The 18V and 19V use the Ku (12 to 18 gigahertz) and Ka (26 to 40 GHz) bands for their spot beams and wide beams…read more.
A satellite with a harpoon, net and drag sail to capture space junk is in orbit and will be tested soon
Phys.org June 29, 2018 NASA is experimenting with the RemoveDebris spacecraft deployed from the ISS, to conduct a series of active debris removal (ADR) technology demonstrations starting in September 2018. Two CubeSats are launched as artificial debris targets to demonstrate some of the technologies. First CubeSat will inflate its onboard balloon to simulate a larger piece of junk. The RemoveDebris spacecraft will then deploy its net to capture it, then guide it into the Earth’s atmosphere where the net will be released. The second CubeSat will be used to test the mothership’s tracking and ranging lasers, its algorithms, and its […]