gravity determination
41mercury — /merr kyeuh ree/, n., pl. mercuries. 1. Chem. a heavy, silver white, highly toxic metallic element, the only one that is liquid at room temperature; quicksilver: used in barometers, thermometers, pesticides, pharmaceutical preparations,… …
42Earth exploration — Introduction the investigation of the surface of the Earth and of its interior. By the beginning of the 20th century most of the Earth s surface had been explored, at least superficially, except for the Arctic and Antarctic regions. Today the… …
43Isaac Newton — Sir Isaac Newton …
44Moon — This article is about Earth s Moon. For moons in general, see Natural satellite. For other uses, see Moon (disambiguation) …
45celestial mechanics — the branch of astronomy that deals with the application of the laws of dynamics and Newton s law of gravitation to the motions of heavenly bodies. [1815 25] * * * Branch of astronomy that deals with the mathematical theory of the motions of… …
46geology — /jee ol euh jee/, n., pl. geologies. 1. the science that deals with the dynamics and physical history of the earth, the rocks of which it is composed, and the physical, chemical, and biological changes that the earth has undergone or is… …
47Nobel Prizes — ▪ 2009 Introduction Prize for Peace The 2008 Nobel Prize for Peace was awarded to Martti Ahtisaari, former president (1994–2000) of Finland, for his work over more than 30 years in settling international disputes, many involving ethnic,… …
48test — 1. To prove; to try a substance; to determine the chemical nature of a substance by means of reagents. 2. A method of examination, as to determine the presence or absence of a definite disease or of some substance in any of the fluids, tissues,… …
49Alhazen — For the Moon crater, see Alhazen (crater). For the asteroid, see 59239 Alhazen. Alhazen Alhazen (Ibn al Haytham) …
50Planetary mass — The four terrestrial planets in the Solar System, to scale. Note that Mars (to the far right) is about half the diameter of the Earth, but only one ninth of the mass …
