Venus is the second-closest planet to the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After theMoon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6. Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°. Venus reaches its maximum brightness shortly before sunrise or shortly after sunset, for which reason it is often called the Morning Star or the Evening Star. Classified as a terrestrial planet, it is sometimes called Earth's "sister planet" because they are similar in size, gravity, and bulk composition. Venus is covered with an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light. Venus has the densest atmosphere of all the terrestrial planets, consisting mostly of carbon dioxide, as it has no carbon cycle to lock carbon back into rocks and surface features, nor organic life to absorb it in biomass. A younger Venus is believed to have possessed Earth-like oceans,[8] but these totally evaporated as the temperature rose, leaving a dusty dry desertscape with many slab-like rocks. The water has most likely dissociated, and, because of the lack of a planetary magnetic field, the hydrogen has been swept into interplanetary space by the solar wind.[9] The atmospheric pressure at the planet's surface is 92 times that of the Earth. It rotates CLOCKWISE
Sunday, November 15, 2009
Venus
Posted by Unknown at 8:14 AM 1 comments
Labels: Planets
Titan
Titan (pronounced /ˈtaɪtən/, or as Ancient Greek: Τῑτάν), or Saturn VI, is the largest moon of Saturn, the only moon known to have a dense atmosphere, and the only object other than Earth for which clear evidence of stable bodies of surface liquid has been found. Titan is the sixth ellipsoidal moon from Saturn. Frequently described as a planet-like moon, Titan has a diameter roughly 50% larger than Earth's moon and is 80% moremassive. It is the second-largest moon in the Solar System, after Jupiter's moon Ganymede, and it is larger by volume than the smallest planet, Mercury, although only half as massive. Titan was the first known moon of Saturn, discovered in 1655 by the Dutch astronomer Christiaan Huygen
Posted by Unknown at 7:50 AM 0 comments
Labels: Moon
Saturday, November 14, 2009
Cabeus Crater
Cabeus is a lunar crater that is located about 100 km (62 mi) from the south pole of the Moon. At this location the crater is seen obliquely from Earth, and it is almost perpetually in deep shadow due to lack of sunlight. Hence, not much detail can be seen of this crater, even from orbit. It lies to the west of the crater Malapert, and to the south-southwest of Newton.
Posted by Unknown at 5:34 AM 0 comments
Labels: Moon