OrbitalHub

NASA Goddard dicit:

When a new NASA space telescope opens its eyes in the mid 2020s, it will peer at the universe through some of the most sophisticated sunglasses ever designed. This multi-layered technology, the coronagraph instrument, might more rightly be called “starglasses”: a system of masks, prisms, detectors and even self-flexing mirrors built to block out the glare from distant stars — and reveal the planets in orbit around them. Normally, that glare is overwhelming, blotting out any chance of seeing orbiting planets. The star’s photons — particles of light — swamp those from the planet when they hit the telescope.

WFIRST’s coronagraph just completed a major milestone: a preliminary design review by NASA. The instrument has met all design, schedule and budget requirements, and can now proceed to the next phase, b uilding hardware for flight. The WFIRST mission’s coronagraph is meant to demonstrate the power of increasingly advanced technology. As it captures light directly from large, gaseous exoplanets, and from disks of dust and gas surrounding other stars, it will point the way to the future: single pixel “images” of rocky planets the size of Earth. Then the light can be spread into a rainbow spectrum, revealing which gases are present in the planet’s atmosphere — perhaps oxygen, methane, carbon dioxide, and maybe even signs of life.

The two flexible mirrors inside the coronagraph are key components. As light that has traveled tens of light-years from an exoplanet enters the telescope, thousands of actuators move like pistons, changing the shape of the mirrors in real time. The flexing of these “deformable mirrors” compensates for tiny flaws and changes in the telescope’s optics. Changes on the mirrors’ surfaces are so precise they can compensate for errors smalle r than the width of a strand of DNA. These mirrors, in tandem with high-tech “masks,” another major advance, squelch the star’s diffraction as well – the bending of light waves around the edges of light-blocking elements inside the coronagraph.

The result: blinding starlight is sharply dimmed, and faintly glowing, previously hidden planets appear. The star-dimming technology also could bring the clearest-ever images of distant star systems’ formative years — when they are still swaddled in disks of dust and gas as infant planets take shape inside.

The instrument’s deformable mirrors and other advanced technology — known as “active wavefront control” — should mean a leap of 100 to 1,000 times the capability of previous coronagraphs.

Video Credit: NASA Goddard

Boston Dynamics dicit:

Atlas uses its whole body — legs, arms, torso — to perform a sequence of dynamic maneuvers that form a gymnastic routine. We created the maneuvers using new techniques that streamline the development process. First, an optimization algorithm transforms high-level descriptions of each maneuver into dynamically-feasible reference motions. Then Atlas tracks the motions using a model predictive controller that smoothly blends from one maneuver to the next. Using this approach, we developed the routine significantly faster than previous Atlas routines, with a performance success rate of about 80%.

Video Credit: Boston Dynamics

NASA dicit:

Arctic sea ice likely reached its 2019 minimum extent of 1.60 million square miles (4.15 million square kilometers) on Sept. 18, tied for second lowest summertime extent in the satellite record, according to NASA and the National Snow and Ice Data Center.

The Arctic sea ice cap is an expanse of frozen seawater floating on top of the Arctic Ocean and neighboring seas. Every year, it expands and thickens during the fall and winter and grows smaller and thinner during the spring and summer. But in the past decades, increasing temperatures have caused marked decreases in the Arctic sea ice extents in all seasons, with particularly rapid reductions in the minimum end-of-summer ice extent. The shrinking of the Arctic sea ice cover can ultimately affect local ecosystems, global weather patterns, and the circulation of the oceans.

Video Credit: NASA Goddard/Lead Producer: Katie Jepson (USRA); Technical Support: Aaron E. Lepsch (ADNET); Scientists: Nathan T. Kurtz (NASA/GSFC), Walt Meier (NASA/GSFC); Lead Visualizers: Trent L. Schindler (USRA), Cindy Starr (GST); Lead Animator: Bailee DesRocher (USRA); Narrator: LK Ward (USRA); Visualizer: Lori Perkins (NASA/GSFC); Lead Writer: Maria-Jose Vinas Garcia (Telophase); Videographers: Kate Ramsayer (Telophase), Jefferson Beck (USRA), John Caldwell (AIMM)

NASA dicit:

NASA astronaut Jessica Meir, Oleg Skripochka of the Russian space agency Roscosmos, and Hazzaa Ali Almansoori from the United Arab Emirates (UAE) launched safely for their mission aboard the International Space Station on the Soyuz MS-15 spacecraft at 9:57 a.m. EDT. [September 25, 2019]

The crew began their six-hour trip to the orbital laboratory during which they will orbit Earth four times.

Video Credit: NASA/Roscosmos

NASA dicit:

The SpaceX CrewDragon spacecraft parachutes successfully deploy during the latest development test. This test simulated a pad abort, where the vehicle is tumbling at low altitude before parachute deploy, validating SpaceX’s parachute models and margins. As a part of NASA’s Commercial Crew Program, SpaceX has been developing and testing the Crew Dragon parachute system, which is comprised of two drogue parachutes and four main ring-sail parachutes—the same type of parachutes that have been commonly and successfully used for human spaceflight in the past.

Video Credit: NASA

Wikipedia dicit:

A reaction control system (RCS) is a spacecraft system that uses thrusters to provide attitude control, and sometimes translation. Use of diverted engine thrust to provide stable attitude control of a short-or-vertical takeoff and landing aircraft below conventional winged flight speeds, such as with the Harrier “jump jet”, may also be referred to as a reaction control system.

An RCS is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow control of rotation (roll, pitch, and yaw).

Reaction control systems often use combinations of large and small (vernier) thrusters, to allow different levels of response. Spacecraft reaction control systems are used for: attitude control during re-entry, stationkeeping in orbit, close maneuvering during docking procedures, control of orientation, or ‘pointing the nose’ of the craft, a backup means of deorbiting, ullage motors to prime the fuel system for a main engine burn.

Because spacecraft only contain a finite amount of fuel and there is little chance to refill them, alternative reaction control systems have been developed so that fuel can be conserved. For stationkeeping, some spacecraft (particularly those in geosynchronous orbit) use high-specific impulse engines such as arcjets, ion thrusters, or Hall effect thrusters. To control orientation, a few spacecraft, including the ISS, use momentum wheels which spin to control rotational rates on the vehicle.

Video Credit: Copenhagen Suborbitals