Video shows engineers at NASA’s Marshall Space Flight Center in Huntsville, Alabama, completing the welds to form the launch vehicle stage adapter (LVSA) for NASA’s Space Launch System (SLS) rocket. The launch vehicle stage adapter in this video will fly on Artemis II, the first crewed mission of NASA’s Artemis program. Upon stacking the upper and lower cones, technicians use advanced robotic tooling and an innovative process called friction stir welding, to join the cones of the LVSA to form one structure.
The next step in the manufacturing process is the installation of the pneumatically actuated frangible joint which sits atop the LVSA and helps separate the core stage and LVSA from the Interim Cryogenic Propulsion Stage (ICPS) during flight. After the core stage launches the rocket, the ICPS provides the power to send the Orion spacecraft and its crew to the Moon.
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917, but was not recognized as such. The first confirmation of detection occurred in 1992. This was followed by the confirmation of a different planet, originally detected in 1988. As of 1 April 2021, there are 4,704 confirmed exoplanets in 3,478 systems, with 770 systems having more than one planet.
There are many methods of detecting exoplanets. Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, multiple planets have been observed around a star. About 1 in 5 Sun-like stars have an “Earth-sized” planet in the habitable zone. Assuming there are 200 billion stars in the Milky Way, it can be hypothesized that there are 11 billion potentially habitable Earth-sized planets in the Milky Way, rising to 40 billion if planets orbiting the numerous red dwarfs are included.
The least massive planet known is Draugr (also known as PSR B1257+12 A or PSR B1257+12 b), which is about twice the mass of the Moon. The most massive planet listed on the NASA Exoplanet Archive is HR 2562 b, about 30 times the mass of Jupiter, although according to some definitions of a planet (based on the nuclear fusion of deuterium), it is too massive to be a planet and may be a brown dwarf instead. Known orbital times for exoplanets vary from a few hours (for those closest to their star) to thousands of years. Some exoplanets are so far away from the star that it is difficult to tell whether they are gravitationally bound to it. Almost all of the planets detected so far are within the Milky Way. There is evidence that extragalactic planets, exoplanets farther away in galaxies beyond the local Milky Way galaxy, may exist. The nearest exoplanets are located 4.2 light-years (1.3 parsecs) from Earth and orbit Proxima Centauri, the closest star to the Sun.
Subscribe to blog posts using RSS
