interesting space facts

Gliese 581 c was the first habitable Extrasolar planet discovered outside the solar system, very close to its Dwarf Star Sun Gliese 581 the climates were with Extreme Heat in the Sunward side and the dark side extremely cold.Its orbit of a year is 13 Earth days and tidal forces could reach up to 400 times.Its distance from the earth is 20.5 light years away and distance from the Sun is 6 642 857 miles away.Its size is 1.5 times larger than that of Earth and its gravity is 1.6 times greater than that of Earth and its surface temperature is 32-104 Degrees F.Gliese 581 its Dwarf Star Sun is a M2.5V class Star.Gliese 581 is 29% smaller than our sun but will appear larger than our Full moon in Gliese 581 c’s Sky.The Terminator or Twilight Zone in Gliese 581 c is the most habitable part of the planet, with water, life is very habitable and creatures live there as well,they are called “Fauna” they are Bird-Like creatures that live in Gliese 581 c.

The Solar System was formed 4.5 Billion Years ago and earth was just a Planet with much Volcanic Activity and after some time it became a water world with not much of land the caused by a Phenomena of Meteors crashing to the earth carrying very high amounts of water.After some time again granite was the main source of land due to Volcanic Activity and Water splashing onto the lava creating Granite, granite is strong and is not much dense causing protection from the strong waves of the seas and oceans.
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merging the topics related to space (not the sticky one)

Named for the Roman goddess of love by the same name, the planet Venus is the second planet from the Sun, at a distance of roughly 108,209,000 kilometers. With an orbital circumference of 680,000,000 kilometers, Venus is just slightly smaller than the Earth and has a very similar chemical composition. For this reason, Venus is commonly referred to as the Earth’s “sister” planet. It takes Venus just under 225 days to orbit the Sun on full time, compared to the 365 day orbital period of the Earth.

Venus actually rotates from east to west, as opposed to west to east which is the common rotating direction of most other planets in space. The atmosphere on the surface of the planet Venus consists mostly of carbon dioxide, with a small trace of nitrogen. The planet Venus has a surface pressure about 90 times that of the Earth, making any life on the planet unsustainable.

Venus is in view to the naked eye from Earth for a period of 2-3 hours before sunrise and 2-3 hours after sunset. Venus is the only other non terrestrial body, besides the moon, that can be seen from Earth during both day and night time hours. At night, Venus is usually the second brightest object in the sky next to the moon.

Venus is the second planet from the Sun and the sixth largest. Venus' orbit is the most nearly circular of that of any planet, with an eccentricity of less than 1%.

Venus (Greek: Aphrodite; Babylonian: Ishtar) is the goddess of love and beauty. The planet is so named probably because it is the brightest of the planets known to the ancients. (With a few exceptions, the surface features on Venus are named for female figures.)

Venus has been known since prehistoric times. It is the brightest object in the sky except for the Sun and the Moon. Like Mercury, it was popularly thought to be two separate bodies: Eosphorus as the morning star and Hesperus as the evening star, but the Greek astronomers knew better. (Venus's apparition as the morning star is also sometimes called Lucifer.)

Since Venus is an inferior planet, it shows phases when viewed with a telescope from the perspective of Earth. Galileo's observation of this phenomenon was important evidence in favor of Copernicus's heliocentric theory of the solar system.

Venus surface Venera 9 surface photo
The first spacecraft to visit Venus was Mariner 2 in 1962. It was subsequently visited by many others (more than 20 in all so far), including Pioneer Venus and the Soviet Venera 7 the first spacecraft to land on another planet, and Venera 9 which returned the first photographs of the surface. The first orbiter, the US spacecraft Magellan
radar map Magellan radar map (false color)
produced detailed maps of Venus' surface using radar. ESA's Venus Express is now in orbit with a large variety of instruments.

Venus' rotation is somewhat unusual in that it is both very slow (243 Earth days per Venus day, slightly longer than Venus' year) and retrograde. In addition, the periods of Venus' rotation and of its orbit are synchronized such that it always presents the same face toward Earth when the two planets are at their closest approach. Whether this is a resonance effect or merely a coincidence is not known.

Venus is sometimes regarded as Earth's sister planet. In some ways they are very similar:

* Venus is only slightly smaller than Earth (95% of Earth's diameter, 80% of Earth's mass).
* Both have few craters indicating relatively young surfaces.
* Their densities and chemical compositions are similar.

Because of these similarities, it was thought that below its dense clouds Venus might be very Earthlike and might even have life. But, unfortunately, more detailed study of Venus reveals that in many important ways it is radically different from Earth. It may be the least hospitable place for life in the solar system.

Venus Venus in visible light from Galileo
The pressure of Venus' atmosphere at the surface is 90 atmospheres (about the same as the pressure at a depth of 1 km in Earth's oceans). It is composed mostly of carbon dioxide. There are several layers of clouds many kilometers thick composed of sulfuric acid. These clouds completely obscure our view of the surface. This dense atmosphere produces a run-away greenhouse effect that raises Venus' surface temperature by about 400 degrees to over 740 K (hot enough to melt lead). Venus' surface is actually hotter than Mercury's despite being nearly twice as far from the Sun.

Venus UV Venus in ultra-violet light
There are strong (350 kph) winds at the cloud tops but winds at the surface are very slow, no more than a few kilometers per hour.

Venus probably once had large amounts of water like Earth but it all boiled away. Venus is now quite dry. Earth would have suffered the same fate had it been just a little closer to the Sun. We may learn a lot about Earth by learning why the basically similar Venus turned out so differently.

Most of Venus' surface consists of gently rolling plains with little relief. There are also several broad depressions: Atalanta Planitia, Guinevere Planitia, Lavinia Planitia. There two large highland areas: Ishtar Terra in the northern hemisphere (about the size of Australia) and Aphrodite Terra along the equator (about the size of South America). The interior of Ishtar consists mainly of a high plateau, Lakshmi Planum, which is surrounded by the highest mountains on Venus including the enormous Maxwell Montes.

Sif Mons Sif Mons (Magellan radar)
Data from Magellan's imaging radar shows that much of the surface of Venus is covered by lava flows. There are several large shield volcanoes (similar to Hawaii or Olympus Mons) such as Sif Mons. Recently announced findings indicate that Venus is still volcanically active, but only in a few hot spots; for the most part it has been geologically rather quiet for the past few hundred million years.

There are no small craters on Venus. It seems that small meteoroids burn up in Venus' dense atmosphere before reaching the surface. Craters on Venus seem to come in bunches indicating that large meteoroids that do reach the surface usually break up in the atmosphere.

The oldest terrains on Venus seem to be about 800 million years old. Extensive volcanism at that time wiped out the earlier surface including any large craters from early in Venus' history.

Venusian coronae Coronae
Venusian pancakes Pancake volcanoes
Magellan's images show a wide variety of interesting and unique features including pancake volcanoes (left) which seem to be eruptions of very thick lava and coronae (right) which seem to be collapsed domes over large magma chambers.

The interior of Venus is probably very similar to that of Earth: an iron core about 3000 km in radius, a molten rocky mantle comprising the majority of the planet. Recent results from the Magellan gravity data indicate that Venus' crust is stronger and thicker than had previously been assumed. Like Earth, convection in the mantle produces stress on the surface. However on Venus the stress is relieved in many relatively small regions instead of being concentrated at the boundaries of large plates as is the case on Earth.

Venus has no magnetic field, perhaps because of its slow rotation.

Venus has no satellites, and thereby hangs a tale.

Venus is usually visible with the unaided eye. Sometimes (inaccurately) referred to as the "morning star" or the "evening star", it is by far the brightest "star" in the sky. There are several Web sites that show the current position of Venus (and the other planets) in the sky. More detailed and customized charts can be created with a planetarium program.

On June 8 2004, Venus passed directly between the Earth and the Sun, appearing as a large black dot travelling across the Sun's disk. This event is known as a "transit of Venus" and is very rare: the last one was in 1882, the next one is in 2012 but after than you'll have to wait until 2117. While no longer of great scientific importance as it was in the past, this event was the impetus for a major journey for many amateur astronomers.

Venus is the second closest planet to the sun. Viewed from earth it is the brightest of the planets. In fact if you know where to look it is possible to see it in broad daylight. At night it is bright enough to cast shadows. It's brightness is due to two things. Firstly it is quite close to earth compared to the other planets. Secondly it is highly reflective and a lot of sunlight bounces off the planet.

Venus was once thought to be a tropical planet rich in vegetation. It was difficult to find out what the surface of Venus was like because it was always covered in cloud.
In the 1970s American and Russian probes were sent through the clouds to measure surface temperature and analyse the atmosphere. None of these probes lasted very long and the reasons soon became clear. The temperature at ground level was 840 degrees fahrenheit, the atmospheric pressure was 90 times that of earth and the atmosphere was highly corrosive. Basically if you send a probe to Venus it will either melt, be crushed or rust. Not somewhere you would want to park your car!

The extremely high temperatures on Venus seem to have been caused by the high quantities of carbon dioxide in the atmosphere which has lead to the greenhouse effect, so an understanding of our sister planet could have profound importance for the future of our own.

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. Except for the Moon 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.

Venus' surface was a subject of speculation until some of its secrets were revealed by planetary science in the twentieth century. It was finally mapped in detail by Project Magellan in 1990–91. The ground shows evidence of extensive volcanism, and the sulfur in the atmosphere may indicate that there have been some recent eruptions.[10][11] However, it is an enigma why no evidence of lava flow accompanies any of the visible caldera. There are a low number of impact craters, demonstrating that the surface is relatively young, approximately half a billion years old. There is no evidence for plate tectonics, possibly because its crust is too strong to subduct without water to make it less viscous. Instead, Venus may lose its internal heat in periodic massive resurfacing events.[12]

The adjective Venusian is commonly used for items related to Venus, though the Latin adjective is the rarely used Venerean; the archaic Cytherean is still occasionally encountered. Venus is the only planet in the Solar System named after a female figure,[a] although three dwarf planets — Ceres, Eris and Haumea — also have feminine names.

^^^ interesting facts
the other 2 topics that i merged have interesting space information