Astronomy
The reference

Venus

Venus is the third most brightness element that we can observ after the Sun and our moon. Venus is also know as the berger star. Generaly we can see it in the sky in the starter evening until soon in the morning. It's relativly easy to recognise Venus because, not like star, Venus do not glitter.

At is surface, they have some cliffs, plains, craters and some volcanic activity trails.

This planet is surround by sulfuric acid cloud. At the equator, they make a complete path around this planet in only four days. Winds on Venus goes up more than 360 kilometers per hour.

Those clouds produce a serre effect and all heat is keep in is atmosphere and go up to 480 Celsius degres.

With the observation, it would be some oceans relics. Some billion years ago, Venus had enought water to cover all is surface, depth as 7 to 20 meters. We do not know, if this water was liquid.

Therefore any proof of oceans, Pionneer's spacecraft datas, reveal that this hypothesis have high probability said Dr Thomas Donahue, from Michigan university, in a press conference at the Ames reserch center.

He had that water maybe had exist since a billion years ago on Venus. "We know in the earth situation, that was enought time to life to be develop. If this matter was on liquid form and if this took some billion years, by analogy with what happen on earth, some primitive kind of life maybe have been develop like stromatolithes form.

The atmosphere density of those gaseous clouds who suround Venus hinder astronomers to describe as well as we can do for some other celestial bodies. The biggest problem of the expedition on Venus by the spacecrafts hed been collate, is the temperature on Venus surface and is atmospheric pression (90 times earth pression).

First and formost, Venus is a volcanic planet, compose of vast plains fill with lava and sprangle of a myriade of volcanics domes with different size: we count about ten thousand of them with 15 km of diameter and about hundred more then 800 km.

Somes pictures from spacecraft let us identify Maat mount, a volcano as high as the Everest mount on earth (8 000 m).

Craters Dimensions
   
Howe 37.3 km
Danilova 47.6 km
Aglaonice 62.7 km

With those 850 craters count. Can let us know that Venus is 800 millions years old.

Because Venus had about 2 or degres of inclinaison, they are no season on Venus.

We can diffentiate two big continents: Aphrodite Terra up north and Ishtar Terra on south. 70 % of the planet surface do not goes up ten 500 meters of altitude.

A strong light yellow cloudy layer, up to 40 à 70 km, surrounding Venus. It's compose of gas, carbonic gas (95 %), azote (2 à 5 %), and also content water and oxygen trace.

Venus is approximativly the same size of the earth.

Maximal distance from the Sun (million of kilometers)
109
Minimum distance from the Sun (million de kilometers)
107.4
Medium distance from the Sun (million de kilometers)
108.2
Medium distance from the Sun (UA) (Earth=1)
0.72
Equator diameter (kilometers)
12 104
Revolution
224.7 Jours
West to east rotation
243 days
Retrograde rotation
Yes
Medium orbital velocity (kilometers per second)
35
Axies inclinaison (Degres)
3
Orbital inclinaison (According to ecliptic)
3.39
Extreme temperature on surface (Celsius degres)
+ 460
Atmosphere
Sulfuric acid clouds
Azote
Carbonic gas
Visibility
Very bright, white
Color
White
Know satellite
-
Rings
-
Volume (Earth = 1)
0.88
Mass (Billion of billion of tons)
4 870
Mass (Earth = 1)
0.815
Density (Water = 1)
5.2
Gravity on surface (Earth = 1)
0.91
Mythology
Roman
Type
Terrestrial
Discover
Antiquity
Equatorial liberation velocity (km/s)
10.3
Principal constituant of the atmosphere
CO2