man-made radiation belt
41earthquake — /errth kwayk /, n. 1. a series of vibrations induced in the earth s crust by the abrupt rupture and rebound of rocks in which elastic strain has been slowly accumulating. 2. something that is severely disruptive; upheaval. [1300 50; ME erthequake …
42meteor and meteoroid — ▪ astronomy Introduction respectively, a glowing streak in the sky (meteor) and its cause, which is a relatively small stony or metallic natural object from space (meteoroid) that enters Earth s atmosphere and heats to incandescence. In modern… …
43Moon — This article is about Earth s Moon. For moons in general, see Natural satellite. For other uses, see Moon (disambiguation) …
44technology, history of — Introduction the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …
45Hypothetical types of biochemistry — are forms of biochemistry speculated to be scientifically viable but not proven to exist at this time. While the kinds of living beings we know on earth commonly use carbon for basic structural and metabolic functions, water as a solvent and DNA… …
46Space habitat — A pair of O Neill cylinders …
47Space debris — populations seen from outside geosynchronous orbit (GEO). Note the two primary debris fields, the ring of objects in GEO, and the cloud of objects in low earth orbit (LEO) …
48global warming — an increase in the earth s average atmospheric temperature that causes corresponding changes in climate and that may result from the greenhouse effect. [1975 80] * * * Potential increase in global average surface temperatures resulting from… …
49Ganymede (moon) — Ganymede Image of Ganymede s anti Jovian hemisphere taken by the Galileo probe. Lighter surfaces, such as in recent impacts, grooved terrain and the whitish north polar cap at upper right, are enriched in water ice. Discovery …
50industrial polymers, major — Introduction chemical compounds used in the manufacture of synthetic industrial materials. In the commercial production of plastics, elastomers, man made fibres, adhesives, and surface coatings, a tremendous variety of polymers are… …
