steady-state model of the universe
61Trihydrogen cation — Protonated molecular hydrogen, trihydrogen cation, or H3+, is one of the most abundant ions in the universe. It is stable in the interstellar medium (ISM) due to the low temperature and low density of interstellar space. The role that H3+ plays… …
62protogalaxy — /proh toh gal euhk see, proh toh gal /, n., pl. protogalaxies. Astron. the large concentration of gas and dust from which a galaxy is formed. [1945 50; PROTO + GALAXY] * * * ▪ cosmology in cosmology, vast cloud of gas that by contraction… …
63Ooty Radio Telescope — Radio Telescope at Ooty Organization Tata Institute of Fundamental Research …
64Atom — The atom is the smallest unit of an element that retains the chemical properties of that element. An atom has an electron cloud consisting of negatively charged electrons surrounding a dense nucleus. The nucleus contains positively charged… …
65JERUSALEM — The entry is arranged according to the following outline: history name protohistory the bronze age david and first temple period second temple period the roman period byzantine jerusalem arab period crusader period mamluk period …
66solar system — the sun together with all the planets and other bodies that revolve around it. [1695 1705] * * * The Sun, its planets, and the small bodies (see asteroid, Centaur object, comet, Kuiper belt, meteorite, and Oort cloud) interplanetary dust and gas… …
67Gaia hypothesis — The study of planetary habitability is partly based upon extrapolation from knowledge of the Earth s conditions, as the Earth is the only planet currently known to harbour life. The Gaia hypothesis, also known as Gaia theory or Gaia principle,… …
68Source counts — The source counts distribution of radio sources from a radio astronomical survey is the cumulative distribution of the number of sources (N) brighter than a given flux density (S). It is one out of a half dozen cosmological tests that was… …
69Type II supernova — The expanding remnant of SN 1987A, a Type II P supernova in the Large Magellanic Cloud. NASA image. A Type II supernova (plural: supernovae) results from the rapid collapse and violent explosion of a massive star. A star must have at least 9… …
70Fusion power — The Sun is a natural fusion reactor. Fusion power is the power generated by nuclear fusion processes. In fusion reactions two light atomic nuclei fuse together to form a heavier nucleus (in contrast with fission power). In doing so they release a …
