This is a big mystery for those who believe in a naturalistic /materialistic explanation of the universe, the solar system and life. Recently, New Scientist published a series of articles on these mysteries that will probably remain unsolved, as they are not willing to accept the one and only logical explanation, namely, that whereas Earth is designed for life, Venus is not.
With temperatures rising to 460 °C, the Venus landscape looks a bit like a painting by Salvador Dali:
“A dim, desolate wasteland pitted by endless sulphuric acid rain and scoured by syrupy winds whose speeds are dictated by the time – fast at dawn and dusk but slowing in the heat of the day. If the choking, largely carbon dioxide atmosphere doesn’t kill you, the heat – a lead-melting– surely will.”
The standard explanation is that Venus is too close to the Sun.
But what about Mars?
They have a somewhat similar explanation. Once again, they assume that the Sun is the culprit although one might think that it’s too far away to do much mischief.