REASONS FOR BEING DIFFERENT:
2.VENUS IS SURELY THE HOTTEST: It's even hotter than Mercury. Amazed? Huh? Venus's a lot further from the Sun, orbiting at a distance of more than 108 million kilometers. Average temperature there is a hellish 735 Kelvin, or 462 degrees Celsius – hot enough to melt lead. Venus is still that same temperature no matter where you go on the planet.
At the North Pole? 735 Kelvin. At night? 735 Kelvin. Daytime at the equator? You get the point.
3.DIFFERENT SURFACE: The surface of Venus is rather smooth in many places, though not nearly as smooth as originally expected . However, we find evidence for many of the same geological features found on Earth: canyons, volcanoes, lava flows, rift valleys, mountains, craters, and plains. There is substantial evidence for local tectonic activity but the surface appears to be a single crustal plate, with little evidence for large-scale horizontal motion of crustal plates as found on the Earth. Why the two planets differ in this aspect of their geology even though we believe them to have similar interiors is not well understood.
The usual explanation is that Venus is a little behind the Earth in geological timescale, and its tectonic activity is just getting started.
<-- The topography of Venus ( BY NASA) [The colours indicate the topography)
4.A LARGE EXCESS OF EMISSION: Pioneer Venus (PV) mission measured the infrared (IR) flux from Venus, and found a large excess emission, implying that the system was imbalanced strongly, and that Venus was found to be much warmer than equilibrium with heatstroke would presume. Any objective view of these observations, does not show any such an imbalance.
5.UNIDENTIFIED FLYING OBJECT: In accordance with Museum of Unnatural Mystery, Venus is the natural object most likely to be mistaken for an unidentified flying object (UFO).
6.HAS PERCENTAGE OF GREENHOUSE EFFECT: There is no reason to believe that a proper greenhouse effect cannot be maintained by the current dry atmosphere of Venus. There is clear observational evidence that the atmosphere once had more water than it does now, and the means by which this water has since escaped can be demonstrated quantitatively. There is no need to invoke any non-greenhouse origin for the elevated tropospheric temperature on Venus.
The center image (a) is centered at the North Pole. The other 4 images are centered around the equator of Venus at (b) 0 degrees longitude, (c) 90 degrees east longitude, (d) 180 degrees and (d) 270 degrees east longitude. The simulated hues are based on color images recorded by the Soviet Venera 13 and 14 spacecraft.
8. ROTATING AND ORBITING THE SUN IN A WEIRD WAY: On the planet Venus, it takes 5,832 hours to complete a full rotation on the axes. One day on the planet Venus is equivalent to 243 days on Earth. Venus takes 1.92 Venus solar days to revolve around the Sun, this is almost equal to 224.7 Earth days or almost 0.615 Earth years. It travels at a speed of 78,341 miles per hour in the Sun's orbit.
9.RIFT VALLEYS: There are rift valleys as large as the East African Rift (the largest on Earth). The image shown below illustrates a rift valley in the West Eistla Region, near Gula Mons and Sif Mons.
The perspective in cases like this is synthesized from radar data taken from different positions in orbit.The East African Rift on Earth is a consequence of tectonic motion between the African and Eurasian plates (the Dead Sea in Israel is also a consequence of this same plate motion). Large rift valleys on Venus appear to be a consequence of more local tectonic activity, since the surface of Venus still appears to be a single plate.
10.INTERIOR: The real tragedy of the Velikovskian scenario comes with the interior of Venus. The interior of Venus, at least in composition, is not unlike the interior of the Earth, which is basically true of Mars and Mercury as well. All of the "terrestrial" planets are made up of varying proportions of pretty much the same stuff, as extensive observations would imply. The most powerful argument that can be raised against the notion of a young Venus is that the current Venus is "Way Cool", or, in other words, much too cold. The known physics of planetary interiors provides perhaps the strongest argument of all against the idea of a young Venus. There is simply no way to dump the excess heat so fast. The papers cited here, and references therein, show how long the thermal time constants are for such material, and expressly show how slow cooling really becomes once a crust is formed. George Talbott's "forced convection" is a fantasy, in view of the real viscosity of planetary material under the physical conditions found inside Venus, or inside the Earth. There can be no question but that Venus would be very much hotter than it is today, if it were thousands of degrees hot only a few thousand years ago.
11.CO2: Venus also shows us what happens when carbon dioxide levels just keep on rising. Radiation from the Sun is absorbed by the planet, and the infrared heat emitted is trapped by the carbon dioxide, which creates a runaway greenhouse effect.