Updated Model Puts Earth On the Edge of the Habitable Zone 264
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."
Re:Well if a "scientist" makes a model then (Score:5, Insightful)
You're right, we shouldn't build models based on math. We shouldn't even try to understand the universe using such abstract tools. We should rely on thought experiments and push models around in sand. We can dress in togas and burn heretics.
Sure (Score:2, Insightful)
Every month or so astronomers find something that, according to their knowledge, should not exist.
I bet they'll soon find a planet outside this new defined zone that has liquid water on its surface.
Re:Well if a "scientist" makes a model then (Score:4, Insightful)
Clouds not only affect sunlight on the day side of the planet but also also radiative heat transfer from the surface on both the day and night sides. Ever notice how much warmer it can be on a cloudy night than on a clear night? Current research indicates that clouds overall probably have a slightly positive effect on global warming but much research still needs to be done.
So clouds have an effect but greenhouse gases still dominate the equations. That affects the accuracy of model he uses but it's likely not an order of magnitude off and so is useful as a starting point to further refine the science.
This binary thinking that something has to be 100% right or it's completely wrong is not how science works.
Re:GW solution (Score:4, Insightful)
"How about 1000 TW of power plants running mass drivers"
If we had a petawatt worth of power plants (presumably fusion)why would we need to worry about global warming - shut down all the fossil fuel burning power plants and use some of that power to pull the excess CO2 out of the atmosphere.
Re:GW solution (Score:4, Insightful)
The earth has been hit by countless enormous hunks of rock during its creation, each with power in the multitudes of times greater than our arsenal, and they didn't manage to move the world.
That's patently false. If any mass hits the earth, we move. How much? Depends on how much mass hit us, but we certainly move. There isn't a threshold where we start moving over a certain amount of mass, the question is how much we move based on the force that was exerted on the planet and the mass of the planet. If anything at all hits us, that number is never exactly 0.