tenuous atmosphere
41Rings of Saturn — The full set of main rings, imaged as Saturn eclipsed the Sun from the vantage of the Cassini spacecraft on 15 September 2006 (brightness is exaggerated). The pale blue dot at the 10 o clock position, outside the main rings and just inside the G… …
42earth — /errth/, n. 1. (often cap.) the planet third in order from the sun, having an equatorial diameter of 7926 mi. (12,755 km) and a polar diameter of 7900 mi. (12,714 km), a mean distance from the sun of 92.9 million mi. (149.6 million km), and a… …
43nebula — nebular, adj. /neb yeuh leuh/, n., pl. nebulae / lee , luy /, nebulas. 1. Astron. a. Also called diffuse nebula. a cloud of interstellar gas and dust. Cf. dark nebula, emission nebula, reflection nebula …
44X-ray astronomy — X rays start at 0.008 nm and extend across the electromagnetic spectrum to 8 nm, over which the Earth s atmosphere is opaque. X ray astronomy is an observational branch of astronomy which deals with the study of X ray observation and detection… …
45Hubble Space Telescope — Infobox Space telescope name = Hubble Space Telescope (HST) caption = The Hubble Space Telescope as seen from Space Shuttle Discovery during its second servicing mission (STS 82) organization = NASAESASTScI alt names = nssdc id =… …
46Jupiter — /jooh pi teuhr/, n. 1. Also called Jove. the supreme deity of the ancient Romans: the god of the heavens and of weather. Cf. Zeus. 2. Astron. the planet fifth in order from the sun, having an equatorial diameter of 88,729 mi. (142,796 km), a mean …
47Pluto — This article is about the dwarf planet. For other uses, see Pluto (disambiguation). Pluto   …
48Sun — This article is about the star. For other uses, see Sun (disambiguation). The Sun …
49plasma — plasmatic /plaz mat ik/, plasmic, adj. /plaz meuh/, n. 1. Anat., Physiol. the liquid part of blood or lymph, as distinguished from the suspended elements. 2. Cell Biol. cytoplasm. 3. whey. 4. a green, faintly translucent chalcedony. 5. Physics. a …
50Noctilucent cloud — Polar mesospheric cloud Noctilucent clouds over Kuresoo bog, Viljandimaa, Estonia Abbreviation NLC/PMC Altitude …
