Telstra has revealed the addition of almost one million new mobile services in the six months to December 2011, but Sensis revenues plummeted 24 percent in 12 months.
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William Atkins
Tuesday, 06 February 2007 21:53
Mercury, the innermost planet to the Sun, will be easy to see in early twilight on February 7th when it will be at its greatest elongation from the Sun (angle between the Sun and Mercury as seen from the Earth). Because it is about 28 degrees east of the Sun at dusk (its maximum elongation from the Sun), it will not fade out from the Sun’s brightness.
Venus, the second closest planet to the Sun, is normally seen in the western sky at sunset. It will climb higher in the sky than Mercury, which will be located to the lower right of Venus. However, both planets will appear to be companions in the sky as one looks low in the west-southwest direction after the Sun has dipped under the horizon.
Mercury is the smallest planet in the solar system. It orbits the Sun in 88 days, as opposed to the Earth’s 365 days. The only spacecraft to visit Mercury was the NASA spacecraft Mariner 10. The spacecraft, launched on November 3, 1973 aboard an Atlas-Centaur rocket at Cape Canaveral, Florida, measured the atmosphere, surface, and general physical characteristics of Mercury during three flybys of the planet between 1974 and 1975.
Future missions to Mercury include the U.S. MESSENGER, in 2011, and the European Union/Japan BepiColombo, in 2019.
Venus orbits the Sun every 224.7 days. Its maximum elongation from the Sun is about 48 degrees. The planet is often referred to as the Evening Star and the Morning Star. Venus has been widely explored both on the ground and from space. The first unmanned space probe to successfully investigate Venus was the NASA Mariner 2 in 1962. It passed about 35,000 kilometers (21,700 miles) from Venus’ surface. Up through 1985, the U.S.S.R. Venera 3 through 16, U.S. Mariner 5 and 10, U.S. Pioneer Venus Orbiter and Multiprobe, and U.S.S.R. Vega were sent to Venus. Since 1986, the U.S. Magellan and U.S. Venus Express have explored Venus.
Future missions to Venus include the Japan PLANET-C, in 2010.
More information about Mercury and Venus is found at: http://seds.lpl.arizona.edu/nineplanets/nineplanets/nineplanets.html.
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