observing
121Sun — This article is about the star. For other uses, see Sun (disambiguation). The Sun …
122Universal Time — (UT) is a timescale based on the rotation of the Earth. It is a modern continuation of Greenwich Mean Time (GMT), i.e., the mean solar time on the meridian of Greenwich, and GMT is sometimes used loosely as a synonym for UTC. In fact the… …
123Vulcan (hypothetical planet) — Vulcan was a small planet proposed to exist in an orbit between Mercury and the Sun in a 19th century hypothesis. This hypothesis has now been rendered obsolete by Albert Einstein s theory of general relativity.Argument for Vulcan s existenceIn… …
124Double star — For other uses, see Double star (disambiguation). In observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. This can happen either because… …
125Observatory — This article is about scientific observatories. For the suburb of Cape Town, see Observatory, Cape Town. For other uses, see The Observatory (disambiguation). The Sphinx Observatory at the Jungfraujoch in the Swiss Alps; high altitude… …
126Weather forecasting — weather forecaster redirects here. For other uses, see Weatherman (disambiguation). Forecast of surface pressures five days into the future for the north Pacific, North America, and north Atlantic ocean. Weather forecasting is the application of… …
127Parity bit — 7 bits of data (number of 1s) 8 bits including parity even odd 0000000 (0) 00000000 10000000 1010001 (3) 11010001 01010001 1101001 (4) 01101001 11101001 1111111 (7) 11111111 …
128Photometry (astronomy) — Photometry is a technique of astronomy concerned with measuring the flux , or intensity of an astronomical object s electromagnetic radiation. Usually, photometry refers to measurement over large wavelength bands of radiation; but, when not only… …
