This video shows how NASA’s James Webb Space Telescope is designed to fold to a much smaller size in order to fit inside the Ariane V rocket for launch to space. The largest, most complex space observatory ever built, must fold itself to fit within a 17.8-foot (5.4-meter) payload fairing, and survive the rigors of a rocket ride to orbit. After liftoff, the entire observatory will unfold in a carefully choreographed series of steps before beginning to make groundbreaking observations of the cosmos.
ICESat-2 (Ice, Cloud, and land Elevation Satellite 2), part of NASA’s Earth Observing System, is a satellite mission for measuring ice sheet elevation and sea ice thickness, as well as land topography, vegetation characteristics, and clouds. ICESat-2, a follow-on to the ICESat mission, was launched on 15 September 2018 from Vandenberg Air Force Base in California, into a near-circular, near-polar orbit with an altitude of approximately 496 km (308 mi). It was designed to operate for three years and carry enough propellant for seven years. The satellite orbits Earth at a speed of 6.9 kilometers per second (4.3 mi/s).
The ICESat-2 mission is designed to provide elevation data needed to determine ice sheet mass balance as well as vegetation canopy information. It will provide topography measurements of cities, lakes and reservoirs, oceans and land surfaces around the globe, in addition to the polar-specific coverage. ICESat-2 also has the ability to detect seafloor topography up to 100 feet (30m) below the surface in clear watered coastal areas. Because the great changes of polar ice cover in global warming are not quantified, one of the main purposes of ICESat-2 is measuring the changing of the elevation of ice sheets by its laser system and lidar to quantify the influence of melting ice sheet in sea-level raising. Additionally, the high accuracy of multiple pulses allows collecting measurement of the heights of sea ice to analyze its change rate during the time.
The ICESat-2 spacecraft was built and tested by Northrop Grumman Innovation Systems in Gilbert, Arizona, while the on board instrument, ATLAS, was built and managed by Goddard Space Flight Center in Greenbelt, Maryland. The ATLAS instrument was designed and built by the center, and the bus was built by and integrated with the instrument by Orbital Sciences (later Orbital ATK). Orbital ATK, which was a global leader in aerospace and defense technologies, was acquired by the Northrop Grumman Corporation on June 6, 2018. The satellite was launched on a Delta II rocket provided by United Launch Alliance. This was the last launch of the Delta II rocket.
Video credit: Credit: NASA’s Scientific Visualization Studio/Kel Elkins (USRA): Lead Visualizer/Ryan Fitzgibbons (USRA): Lead Producer/Alek A. Petty (University of Maryland): Scientist/Thomas A. Neumann Ph.D. (NASA/GSFC): Scientist/Nathan T. Kurtz (NASA/GSFC): Scientist
An electrically-powered spacecraft propulsion system uses electrical, and possibly also magnetic fields, to change the velocity of a spacecraft. Most of these kinds of spacecraft propulsion systems work by electrically expelling propellant (reaction mass) at high speed.
Electric thrusters typically use much less propellant than chemical rockets because they have a higher exhaust speed (operate at a higher specific impulse) than chemical rockets. Due to limited electric power the thrust is much weaker compared to chemical rockets, but electric propulsion can provide a small thrust for a long duration of time. Electric propulsion can achieve high speeds over long periods and thus can work better than chemical rockets for some deep space missions.
Electric propulsion is now a mature and widely used technology on spacecraft. Russian satellites have used electric propulsion for decades and it is predicted that by 2020, half of all new satellites will carry full electric propulsion. As of 2019, over 500 spacecraft operated throughout the Solar System use electric propulsion for station keeping, orbit raising, or primary propulsion. In the future, the most advanced electric thrusters may be able to impart a Delta-v of 100 km/s, which is enough to take a spacecraft to the outer planets of the Solar System (with nuclear power), but is insufficient for interstellar travel. An electric rocket with an external power source (transmissible through laser on the photovoltaic panels) has a theoretical possibility for interstellar flight. However, electric propulsion is not a method suitable for launches from the Earth’s surface, as the thrust for such systems is too weak.
Preparing to explore the surface of the Moon goes well beyond designing and building safe spacecraft and spacesuits. NASA also has to ensure the surface vehicles and suits have the mobility required to do science, and that astronauts have the tools they need to identify and scoop up rock and soil samples. Additionally, NASA astronauts are trained in geology, spending countless hours practicing doing science at locations on Earth that resemble regions they might see on the Moon. All this is done in an effort to establish a long-term presence on the Moon and to help answer some outstanding science questions about the history of Earth and of the solar system.
Video credit: NASA’s Goddard Space Flight Center/James Tralie (ADNET): Lead Producer, Lead Editor/Lonnie Shekhtman (ADNET): Lead Writer/Kelsey Young (NASA/GSFC): Scientist/Trevor Graff (Jacobs Technology): Scientist/Aaron E. Lepsch (ADNET): Technical Support/”Saana” and “Seasons” by Torsti Juhani Spoof from Universal Production Music
The sky crane system lowers the rover with a 7.6 m (25 ft) tether to a soft landing—wheels down—on the surface of Mars. This system consists of a bridle lowering the rover on three nylon tethers and an electrical cable carrying information and power between the descent stage and rover. As the support and data cables unreel, the rover’s six motorized wheels snap into position. At roughly 7.5 m (25 ft) below the descent stage the sky crane system slows to a halt and the rover touches down. After the rover touches down, it waits two seconds to confirm that it is on solid ground by detecting the weight on the wheels and fires several pyros (small explosive devices) activating cable cutters on the bridle and umbilical cords to free itself from the descent stage. The descent stage then flies away to a crash landing site 650 m (2,100 ft) away.
The Orion Multi-Purpose Crew Vehicle (Orion MPCV) is a class of partially reusable space capsule planned to be used after 2021 in NASA’s human spaceflight programs. The spacecraft consists a Crew Module (CM) manufactured by Lockheed Martin and the European Service Module (ESM) manufactured by Airbus Defence and Space. Capable of supporting a crew of six beyond low Earth orbit, Orion can last 21 days undocked and up to six months docked. It is equipped with solar power, an automated docking system, and glass cockpit interfaces modeled after those used in the Boeing 787 Dreamliner. A single AJ10 engine provides the spacecraft’s primary propulsion, while eight R-4D-11 engines, and six pods of custom reaction control system engines developed by Airbus, provide the spacecraft’s secondary propulsion. Although compatible with other launch vehicles, Orion is primarily designed to launch atop a Space Launch System (SLS) rocket, with a tower launch escape system.
Orion was originally conceived by Lockheed Martin as a proposal for the Crew Exploration Vehicle (CEV) to be used in NASA’s Constellation program. Lockheed Martin’s proposal defeated a competing proposal by Northrop Grumman, and was selected by NASA in 2006 to be the CEV. Originally designed with a service module featuring a new “Orion Main Engine” and a pair of circular solar panels, the spacecraft was to be launched atop the Ares I rocket with either a traditional launch escape system or the experimental Max Launch Abort System equipped. Following the cancellation of the Constellation program in 2010, Orion was heavily redesigned for use in NASA’s Journey to Mars initiative; later named Moon to Mars. The SLS replaced the Ares I as Orion’s primary launch vehicle, and the service module was replaced with a design based on the European Space Agency’s Automated Transfer Vehicle. A development version of Orion’s CM was launched in 2014 during Exploration Flight Test-1, while at least four test articles have been produced. As of 2020, three flight-worthy Orion spacecraft are under construction, with an additional one ordered for use in NASA’s Artemis program; the first of these is due to be launched in 2021 during Artemis 1.
Subscribe to blog posts using RSS
