Of the four inner planets, earth holds an entire ecosystem that goes from deep in the earth to high in the atmosphere. Of the other three, we still don’t know if there is life under the surface of Mars. We know the surface and atmosphere is sterile. That is because there is no liquid water and the thin atmosphere lets in way more ultraviolet and other radiation that sterilizes the surface.
Mercury is a lot like the moon, a large round rock that is so close to the sun it is bombarded with constant heat and radiation that would make life as we know unthinkable. Then there is Venus. At one time, the atmosphere on Venus was believed to b e about 90˚F warmer than earth and the planet had oceans. That may seem hot, but it was not to warm for some type of life to have evolved there. Then the green house affect kicked and the temperature on Venus kept rising, boiling off the oceans and the thick atmosphere, probably similar to earth at that time, leached the carbon into the air raising the temperatures higher. Today the surface on Venus is almost 900˚F, The cloud tops cool down, but are laced with droplets of sulfuric acid and sulfur dioxide.
What’s a little scary about Venus is that it is considered Earth’s twin and it is Earth’s closest planet. It raises a simple question. Is the earth close enough to the sun for such a change to boil its oceans, leach out it carbon and leave this planet lifeless? It may be likely that three of the four inner planets all had life on their surfaces billions of years ago. The life process stopped completely on Venus and if it exist at all on Mars today, it exist as mere remnants of a planet that also had an earth like atmosphere. So can earth end up a desolate bone dry windswept lifeless body as its two closest neighbors? If life did evolve on these three planets, it died out first on Venus and the surface of Mars became lifeless about a billion or two years ago. That means that planets with life may not stay that way indefinitely.
All the idiots who claim global warming is a scam should take a close look at our nearest planetary neighbor. It would take millions of years for the Earth to get hot enough for all the oceans to boil off and the atmosphere to leach out all the carbon. But do we want to ignore the signs that we may be starting something we can’t stop?
Do we want to be responsible for the greatest extinction since the dinosaurs died out? Only a fool would ignore these possibilities and those who do it now are in denial and lazy.
For earth day, take a look at our sister planet and consider the possibilities.