Search results
Results From The WOW.Com Content Network
Currently most of the objects of mass between 10 9 kg to 10 12 kg (less than 1000 teragrams (Tg)) listed here are near-Earth asteroids (NEAs). The Aten asteroid 1994 WR12 has less mass than the Great Pyramid of Giza, 5.9 × 10 9 kg. For more about very small objects in the Solar System, see meteoroid, micrometeoroid, cosmic dust, and ...
Ursa Major ( / ˈɜːrsə ˈmeɪdʒər /; also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) bear", referring to and contrasting it with nearby Ursa Minor, the lesser bear. [1] In antiquity, it was one of the original 48 ...
Current estimates place the probability of finding an Earth-like planet around Alpha Centauri at roughly 75%. The observational thresholds for planet detection in the habitable zones by the radial velocity method are currently (2017) estimated to be about 50 M E for Alpha Centauri A, 8 M E for Alpha Centauri B, and 0.5 M E for Proxima Centauri.
Angular diameter: the angle subtended by an object. The angular diameter, angular size, apparent diameter, or apparent size is an angular distance describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the visual angle, and in optics, it is the angular aperture (of a lens ).
Dark sky image with some objects around Pinwheel Galaxy (M 101). The quarter in the lower right shows the tail of Ursa Major with the stars Mizar, Alcor and Alkaid.. The Pinwheel Galaxy (also known as Messier 101, M101 or NGC 5457) is a face-on, unbarred, and counterclockwise spiral galaxy located 21 million light-years (6.4 megaparsecs) from Earth in the constellation Ursa Major.
Ophiuchus ( / ˌɒfiˈjuːkəs /) is a large constellation straddling the celestial equator. Its name comes from the Ancient Greek ὀφιοῦχος ( ophioûkhos ), meaning "serpent-bearer", and it is commonly represented as a man grasping a snake. The serpent is represented by the constellation Serpens.
Geosynchronous orbit. A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day ). The synchronization of rotation and orbital period means that, for an observer on Earth's surface, an object in ...
Planisphere. In astronomy, a planisphere ( / ˈpleɪ.nɪˌsfɪər, ˈplæn.ɪ -/) is a star chart analog computing instrument in the form of two adjustable disks that rotate on a common pivot. It can be adjusted to display the visible stars for any time and date. It is an instrument to assist in learning how to recognize stars and constellations.