OrbitalHub

Wikipedia dicit:

In 2019, NASA’s James Webb Space Telescope celebrated the full mechanical and electrical assembly of the world’s largest, most powerful space science observatory ever built. Webb’s two halves have been physically put together and its wiring harnesses and electrical interfaces have been connected.

Following assembly, the Webb team moved on to successfully send deployment and tensioning commands to all five layers of its sunshield, which is designed to protect the observatory’s mirrors and scientific instruments from light and heat, primarily from the Sun.

Ensuring mission success for an observatory of this scale and complexity is a challenging endeavor. All of the telescope’s major components have been tested individually through simulated environments they would encounter during launch, and while orbiting a million miles away from Earth. Now that Webb is fully assembled, it must meet rigorous observatory-level standards. The complete spacecraft reacts and performs differently to testing environments than when its components are tested individually.

Following Webb’s successful sunshield deployment and tensioning test, team members have nearly finished the long process of perfectly folding the sunshield back into its stowed position for flight, which occupies a much smaller space than when it is fully deployed. Then, the observatory will be subjected to comprehensive electrical tests and one more set of mechanical tests that emulate the launch acoustic and vibration environment, followed by one final deployment and stowing cycle on the ground, before its flight into space. The James Webb Space Telescope is scheduled to launch in 2021.

Video credit: NASA’s Goddard Space Flight Center, Greenbelt, Md./Aaron E. Lepsch (ADNET): Technical Support/Michael McClare (KBRwyle): Videographer/Sophia Roberts (AIMM): Videographer/Michael P. Menzel (AIMM): Video Editor

Wikipedia dicit:

OmegA is a launch vehicle in development by Northrop Grumman as an NSSL replacement program intended for national security and commercial satellites.

OmegA is similar to the defunct Ares I and Liberty projects, both of which consisted of a five segment Space Shuttle Solid Rocket Booster (SRB) and a cryogenic second stage. Ares I would have combined a five-segment SRB with a J-2X powered second stage, while Liberty would have used a five-segment SRB with the core stage of the European Ariane 5 as a second stage. By comparison, OmegA consists of new composite solid rocket stages with a cryogenic upper stage provided by Aerojet Rocketdyne. This is replacing earlier plans to use an upper stage provided by Blue Origin. It is intended to be launched from Kennedy Space Center LC-39B or Vandenberg Air Force Base SLC-6.

OmegA is proposed as a vehicle to launch national security satellites for the United States Air Force, and could launch other government and commercial payloads, including to geostationary transfer orbit. Crewed spacecraft could also be launched, just as the predecessor Ares I and Liberty rockets, which were designed to launch the Orion space capsule.

Video credit: Northrop Grumman

NASA dicit:

OSIRIS-REx is a NASA mission to explore near-Earth asteroid Bennu and return a sample to Earth. Prior to arriving at Bennu, mission planners had expected the asteroid’s surface to consist largely of fine-grained material, like a sandy beach. When OSIRIS-REx arrived in December 2018, however, it was greeted by a rocky world covered with boulders.

This unexpected roughness means that there are few places on Bennu where OSIRIS-REx can safely touch down and collect a sample. After a year of studying the asteroid, the mission announced a primary sample collection site, which they designated “Nightingale,” along with a backup site called “Osprey.” In August 2020, OSIRIS-REx will descend to Nightingale and attempt to collect up to four-and-a-half pounds of loose material, for return to Earth in 2023.

Video credit: NASA Goddard

NASA dicit:

Engineers at Northrop Grumman’s facility in Elkton, Maryland successfully conducted the third and final test of the attitude control motor (ACM) that provides steering for the Launch Abort System (LAS) on NASA’s Orion spacecraft, qualifying the motor for Artemis II, Orion’s first mission with astronauts. The LAS, consisting of three solid rocket motors, is designed to carry crew to safety in the event of an emergency during launch or ascent atop the agency’s Space Launch System rocket.

During the 30-second test, eight high pressure valves directed more than 7,000 pounds of thrust in multiple directions while firing at freezing conditions. All three motors on the LAS will be qualified for crewed flights ahead of Artemis II, another step that brings NASA closer to sending the first woman and next man to the Moon by 2024.

Video credit: NASA Johnson

Wikipedia dicit:

The Artemis program is an ongoing crewed spaceflight program carried out predominately by NASA, U.S. commercial spaceflight companies, and international partners such as the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), and the Canadian Space Agency (CSA) with the goal of landing “the first woman and the next man” on the Moon, specifically at the lunar south pole region by 2024. NASA sees Artemis as the next step towards the long-term goal of establishing a sustainable presence on the Moon, laying the foundation for private companies to build a lunar economy, and eventually sending humans to Mars.

Video credit: NASA

NASA dicit:

A new study of observations from NASA’s Fermi Gamma-ray Space Telescope has discovered a faint but sprawling glow around a nearby pulsar. If visible to the human eye, this gamma-ray halo would appear larger in the sky than the famed Big Dipper star pattern. The halo suggests this same pulsar could be responsible for a decade-long puzzle about one type of cosmic particle arriving from beyond the solar system that is unusually abundant near Earth — positrons, the antimatter version of electrons.

A neutron star is the crushed core left behind when a star much more massive than the Sun runs out of fuel, collapses under its own weight and explodes as a supernova. We see some neutron stars as pulsars, rapidly spinning objects emitting beams of radio waves, light, X-rays and gamma rays that, much like a lighthouse, regularly sweep across our line of sight from Earth.

Geminga (pronounced geh-MING-a) is among the brightest pulsars at gamma-ray energies. To study its halo, scientists had to subtract out all other sources of gamma rays, including diffuse light produced by cosmic ray collisions with interstellar gas clouds. Ten different models of interstellar emission were evaluated. What remained when these sources were removed was a vast, oblong glow spanning some 20 degrees — about 40 times the apparent size of a full Moon — at an energy of 10 billion electron volts (GeV), and even larger at lower energies.

The team determined that Geminga alone could be responsible for as much as 20% of the high-energy positrons seen by other space experiments. Extrapolating this to the cumulative emission of positrons from all pulsars in our galaxy, the scientists say it’s clear that pulsars remain the best explanation for the observed excess of positrons.

Video credit: NASA’s Goddard Space Flight Center/Scott Wiessinger (USRA): Producer/Francis Reddy (University of Maryland College Park): Science writer/Mattia Di Mauro (Catholic University of America): Visualizer/Mattia Di Mauro (Catholic University of America): Scientist