Mercury (planet)Mercury is the first planet from the Sun and the smallest in the Solar System. It is a rocky planet with a trace atmosphere and a surface gravity slightly lower than that of Mars. The surface of Mercury is similar to Earth's Moon, being cratered, with an expansive rupes system generated from thrust faults, and bright ray systems, formed by ejecta.
CometNatural object in space that releases gasA comet is an icy, small Solar System body or interstellar object that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, and sometimes a tail of gas and dust gas blown out from the coma.
Double Asteroid Redirection TestThe Double Asteroid Redirection Test (DART) was a NASAspace mission to test a method of planetary defense against near-Earth objects (NEOs). It was designed to assess how much a spacecraft impact can deflect an asteroid by hitting it head-on. The target asteroid, Dimorphos, is a 525 feet (160 m) wide moonlet of the asteroid Didymos; neither asteroid poses an impact threat to Earth, but their joint characteristics made them an ideal target.
DimorphosDimorphos (formal designation (65803) Didymos I; provisional designationS/2003 (65803) 1) is a natural satellite or moon of the near-Earth asteroid65803 Didymos, with which it forms a binary system. The moon was discovered on 20 November 2003 by Petr Pravec in collaboration with other astronomers worldwide. Dimorphos has a diameter of 177 meters (581 ft) across its longest extent.
MESSENGERMESSENGER was a NASA robotic space probe that orbited the planet Mercury between 2011 and 2015, studying Mercury's chemical composition, geology, and magnetic field. The name is a backronym for Mercury Surface, Space Environment, Geochemistry, and Ranging, and a reference to the messenger god Mercury from Roman mythology. MESSENGER was launched aboard a Delta II rocket in August 2004.
Kerbal Space ProgramKerbal Space Program is a 2015 space flight simulation video game developed by Mexican studio Squad for Linux, macOS, Windows, PlayStation 4, PlayStation 5, Xbox Series X/S and Xbox One. In the game, players direct the space program of a species of green humanoid aliens known as Kerbals. The game features a pseudorealistic orbital physics engine, allowing for various real-life orbital maneuvers such as Hohmann transfer orbits and orbital rendezvous.
AtmosphereAn atmosphere is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. The name originates from Ancient Greek ἀτμός (atmós) 'vapour, steam' and σφαῖρα (sphaîra) 'sphere'. An object acquires most of its atmosphere during its primordial epoch, either by accretion of matter or by outgassing of volatiles.
EuphemismMild or indirect word or expression Sign in a Rite Aid drugstore using common euphemisms for (from top): contraceptivesmenstrual pads and tamponsadult diapers A euphemism is the substitution of a potentially offensive or unpleasant word or expression with one that is more pleasant or inoffensive. Some euphemisms are humorous, while others use mild or neutral language to downplay certain concepts.
Emergency landingAn emergency landing is a premature landing made by an aircraft in response to an emergency involving an imminent or ongoing threat to the safety and operation of the aircraft, or involving a sudden need for a passenger or crew on board to terminate the flight (such as a medical emergency). It typically involves a forced diversion to the nearest or most suitable airport or airbase, or an off airport landing or ditching if the flight cannot reach an airfield.
AerobrakingAerobraking is a spaceflight maneuver that reduces the high point of an elliptical orbit (apoapsis) by flying the vehicle through the atmosphere at the low point of the orbit (periapsis). The resulting drag slows the spacecraft. Aerobraking is used when a spacecraft requires a low orbit after arriving at a body with an atmosphere, as it requires less fuel than using propulsion to slow down.
Jonathan McDowellJonathan Christopher McDowell (born 6 July 1960) is a British-American astronomer and astrophysicist who worked at the Harvard–Smithsonian Center for Astrophysics's Chandra X-ray Center. McDowell is the author and editor of Jonathan's Space Report, an e-mail-distributed newsletter documenting satellite launches.
LithosphereA lithosphere is the rigid outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more. The crust and upper mantle are distinguished on the basis of chemistry and mineralogy.ApsisAn apsis (from Ancient Greek (hapsís)'arch, vault' (third declension); pl.apsides ) is one of the two extreme points in the orbit of a planetary body about its primary body, either the farthest point ('apoapsis) or the nearest point (periapsis). The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two apsides. Apsides pertaining to orbits around different bodies have distinct names to differentiate themselves from other apsides.*As an Amazon Associate I earn from qualifying purchases.