Updated Model Puts Earth On the Edge of the Habitable Zone

cylonlover writes with news of an update to the model used for calculating the habitable zone around stars shifting things out a bit. From the article: "Researchers at Penn state have developed a new method for calculating the habitable zone (original paper, PDF) around stars. The computer model based on new greenhouse gas databases provides a tool to better estimate which extrasolar planets with sufficient atmospheric pressure might be able to maintain liquid water on their surface. The new model indicates that some of the nearly 300 possible Earth-like planets previously identified might be too close to their stars to to be habitable. It also places the Solar System's habitable zone between 0.99 AU (92 million mi, 148 million km) and 1.70 AU (158 million mi, 254 million km) from the Sun. Since the Earth orbits the Sun at an average distance of one AU, this puts us at the very edge of the habitable zone."

Comments

Wow

[Arancaytar]

The whole "Earth is fine-tuned for life" stuff has been debunked for ages (but still circulates thanks to creationists), but it's pretty amazing to consider our planet could be more than 1.5 times as far out as it is now, and still remain habitable.

Also, note that the Earth's perihelion places us at 0.983AU. If these numbers are correct, our orbit actually leaves the habitable zone for a brief period every year.

Re:GW solution

[girlintraining]

A few hundred well-placed nuclear bombs ought to do it.

If the goal is a nuclear winter, sure. If you're trying to move the planet... how can I put this as succinctly as possible: If we detonated every nuke we had on one side of the planet, we'd succeed only in leaving one side of the planet uninhabitable. It wouldn't move the planet by any appreciable amount. The subsequent earthquakes would probably do more, by affecting spin. People seem to forget in orbital mechanics, to move in one direction, you have to displace an equal amount of mass x energy in the opposite direction. All a nuke would do is move the air around and leave a hole in the ground. Nothing would be ejected into space, and therefore, no movement.

I know you're trying to be funny, but after awhile, I get tired of the "a nuke is powerful enough to do anything!" thinking. I blame Bruce Willis.