jupiter's atmosphere is hydrogen and helium
51physical science — physical scientist. 1. any of the natural sciences dealing with inanimate matter or with energy, as physics, chemistry, and astronomy. 2. these sciences collectively. [1835 45] * * * Introduction the systematic study of the inorganic world …
52Atmospheric escape — There are several different processes that can lead to the escape of a planetary atmosphere. In some cases this can be a very important process; for example, both Venus and Mars have probably lost much of their water due to atmospheric escape… …
53Extrasolar planet — Planet Fomalhaut b (inset against Fomalhaut s interplanetary dust cloud) imaged by the Hubble Space Telescope s coronagraph (NASA photo) …
54List of astronomy acronyms — This is a compilation of acronyms commonly used in astronomy. Most of the acronyms are drawn from professional astronomy and are used quite frequently in scientific publications. However, a few of these acronyms are frequently used by the general …
55Astronomy — (from the Greek words astron (ἄστρον), star , and nomos (νόμος), law ) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earth s atmosphere (such as the cosmic… …
56Definition of planet — Photograph of the crescent planet Neptune (top) and its moon Triton (center) …
57Outer space — For other uses, see Outer space (disambiguation). The boundaries between the Earth s surface and outer space, at the Kármán line, 100 km (62 mi) and exosphere at 690 km (430 mi). Not to scale Outer space is the void that exists beyond any… …
58Rogue planet — This article is about a type of astronomical object. For other uses, see Rogue planet (disambiguation). Artist s conception of a Jupiter size rogue planet. A rogue planet (also known as an interstellar planet, or orphan planet) is a planetary… …
59Geology of solar terrestrial planets — The geology of solar terrestrial planet mainly deals with the geological aspects of four planets of the Solar system namely, Mercury, Venus, Earth and Mars and one terrestrial dwarf planet, Ceres. Objects like Pluto are similar to terrestrial… …
60History of the Earth — For the history of modern humans, see History of the world. Geological time put in a diagram called a geological clock, showing the relative lengths of the eons of the Earth s history The history of the Earth describes the most important events… …
