“The space industry demands the most rigorous vibration testing in the world. The first two minutes of a satellite’s space flight are the toughest, as it experiences the extreme vibration of launch. It is essential to test satellites and their component parts in advance of the launch to ensure they will not be shaken to pieces.
The multi-axis vibration test facility HYDRA complements the Electrodynamic shakers, increasing the spectrum of vibration testing available to ESTEC Test Centre customers. It is capable of generating vibrations equivalent to an earthquake of 7.5 on the Richter scale.”
“Advanced Extremely High Frequency (AEHF) is a series of communications satellites operated by the United States Air Force Space Command. They will be used to relay secure communications for the Armed Forces of the United States, the British Armed Forces, the Canadian Forces and the Royal Netherlands Armed Forces. The system will consist of six satellites in geostationary orbits, four of which have been launched. AEHF is backward compatible with, and will replace, the older Milstar system and will operate at 44 GHz Uplink (EHF band) and 20 GHz Downlink (SHF band). AEHF systems is a joint service communications system that will provide survivable, global, secure, protected, and jam-resistant communications for high-priority military ground, sea and air assets. It is the follow-on to the Milstar system. AEHF systems’ uplinks and crosslinks will operate in the extremely high frequency (EHF) range and downlinks in the super high frequency (SHF) range.
AEHF satellites use a large number of narrow spot beams directed towards the Earth to relay communications to and from users. Crosslinks between the satellites allow them to relay communications directly rather than via a ground station. The satellites are designed to provide jam-resistant communications with a low probability of interception. They incorporate frequency-hopping radio technology, as well as phased array antennas that can adapt their radiation patterns in order to block out potential sources of jamming.
AEHF incorporates the existing Milstar low data-rate and medium data-rate signals, providing 75–2400 bit/s and 4.8 kbit/sec–1.544 Mbit/s respectively. It also incorporates a new signal, allowing data rates of up to 8.192 Mbit/s. When complete, the space segment of the AEHF system will consist of six satellites, which will provide coverage of the surface of the Earth between latitudes of 65 degrees north and 65 degrees south. For northern polar regions, the Enhanced Polar System acts as an adjunct to AEHF to provide EHF coverage.”
“About a year ago, astronomers excitedly reported the first detection of electromagnetic waves, or light, from a gravitational wave source. Now, a year later, researchers are announcing the existence of a cosmic relative to that historic event. The discovery was made using data from telescopes including NASA’s Chandra X-ray Observatory, Fermi Gamma-ray Space Telescope, Neil Gehrels Swift Observatory, the NASA/ESA Hubble Space Telescope, and the Discovery Channel Telescope (DCT).
The object of the new study, called GRB150101B, was first reported as a gamma-ray burst detected by Fermi in January 2015. This detection and follow-up observations at other wavelengths show GRB150101B shares remarkable similarities to the neutron star merger and gravitational wave source discovered by Advanced Laser Interferometer Gravitational Wave Observatory (LIGO) and its European counterpart Virgo in 2017 known as GW170817. The latest study concludes that these two separate objects may, in fact, be related.”
“Operation IceBridge is NASA’s longest-running aerial survey of polar ice. During the survey, designed to assess changes in the ice height of several glaciers draining into the Larsen A, B and C embayments, IceBridge senior support scientist Jeremy Harbeck saw a very sharp-angled, tabular iceberg floating among sea ice just off of the Larsen C ice shelf.”
Subscribe to blog posts using RSS
