OrbitalHub

NASA dixit:

“This is an incredible aerial view of NASA’s Recovery Team and the US Navy practicing recovering a test version of the Orion crew capsule after it splashes down. Underway Recovery Test-7 is one in a series of tests to verify and validate procedures and hardware that will be used to recover the Orion spacecraft after it splashes down in the Pacific Ocean following deep space exploration missions.”

Video Credit: NASA

NASA dixit:

“A planetary science Ph.D. student at University College London’s Mullard Space Science Laboratory in the United Kingdom, has developed a new image-processing technique to mine through the wealth of data about comet tails. The findings offer the first observations of striations forming in the tails, and an unexpected revelation about the Sun’s effect on comet dust.

Understanding how dust behaves in the tail — how it fragments and clumps together — can teach scientists a great deal about similar processes that formed dust into asteroids, moons and even planets all those billions of years ago. With this study, scientists gain new insights to long-held mysteries. The work sheds light on the nature of striated comet tails from the past and provides a crucial lens for studying other comets in the future. But it also opens a new line of questioning: What role did the Sun have in our solar system’s formation and early history?”

Video Credit: NASA Goddard/Genna Duberstein

NASA dixit:

“Every year, the ozone hole over Antarctica reaches an annual maximum extent during southern winter. The depletion of ozone by chlorofluorocarbons (CFCs) happens faster at colder temperatures and slows down as temperatures warm, so each October, the ozone layer begins to heal again for the year.

Scientists from NASA and NOAA work together to track the ozone layer throughout the year and determine when the hole reaches its annual maximum extent. This year, the South Pole region of Antarctica was slightly colder than the previous few years, so the ozone hole grew larger. However, scientists from NASA have developed models to predict what the ozone layer would have looked like without the Montreal Protocol, which banned the release of CFCs. Although the 2018 hole was slightly larger than that of 2017 or 2016, it was still much smaller than it would have been without the Montreal Protocol.”

Video Credit: NASA

ESA dixit:

“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.”

Video Credit: ESA

Wikipedia dixit:

“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.”

Video Credit: ULA

NASA dixit:

“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.”

Video Credit: NASA