galactic space radiation
51Black hole — For other uses, see Black hole (disambiguation). Simulated view of a black hole (center) in front of the Large Magellanic Cloud. Note the gravitat …
52Galaxy — This article is about the astronomical structure. For other uses, see Galaxy (disambiguation). NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 55,000 light years in diameter and approximately 60 million light… …
53Cosmic ray — For the film, see Cosmic Ray (film). Cosmic radiation redirects here. For some background types of cosmic radiation, see cosmic background radiation and cosmic background. The energy spectrum for cosmic rays Cosmic rays are energetic charged… …
54General relativity — For a generally accessible and less technical introduction to the topic, see Introduction to general relativity. General relativity Introduction Mathematical formulation Resources …
55galaxy — /gal euhk see/, n., pl. galaxies. 1. Astron. a. a large system of stars held together by mutual gravitation and isolated from similar systems by vast regions of space. b. (usually cap.) See Milky Way. 2. any large and brilliant or impressive… …
56Astronomy — (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… …
57Habitable zone — Goldilocks planet redirects here. For the planet initially nicknamed Goldilocks , see 70 Virginis b. For other uses, see Goldilocks (disambiguation). Goldilocks Zone and Comfort zone (astronomy) redirect here. For other uses, see Comfort zone… …
58telescope — /tel euh skohp /, n., adj., v., telescoped, telescoping. n. 1. an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens… …
59Megamaser — A megamaser is a type of astrophysical maser, which is a naturally occurring source of stimulated spectral line emission. Megamasers are distinguished from astrophysical masers by their large isotropic luminosity. Megamasers produce roughly 103… …
60Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …
