by Chris Peterson » Wed Jun 26, 2013 7:43 pm
neufer wrote:I prefer to say that they orbit around a common barycenter roughly half way between them.
That's fine. Dynamically, the local group is basically a two-body system made up of the Milky Way and Andromeda, slightly perturbed by other members.
Man made global warming is caused by the Earth retaining slightly more solar energy than it radiates, due primarily to the annual dumping of 23 billion tons of carbon dioxide into the atmosphere. (But right after that I would blame Andromeda.)
The Earth radiates so little internal heat in comparison with solar re-radiation, that I think it's fair to say all global warming is caused by an imbalance between the solar radiation we receive and what gets re-radiated. The man-made component (which right now is virtually all of it) is, of course, caused primarily by the changes we ourselves are making to the atmosphere (which produces a cascade of secondary elements, too).
[quote="neufer"]I prefer to say that they orbit around a common barycenter roughly half way between them.[/quote]
That's fine. Dynamically, the local group is basically a two-body system made up of the Milky Way and Andromeda, slightly perturbed by other members.
[quote][u]Man made[/u] global warming is caused by the Earth retaining slightly more solar energy than it radiates, due [u]primarily[/u] to the annual dumping of 23 billion tons of carbon dioxide into the atmosphere. (But right after that I would blame Andromeda.)[/quote]
The Earth radiates so little internal heat in comparison with solar re-radiation, that I think it's fair to say all global warming is caused by an imbalance between the solar radiation we receive and what gets re-radiated. The man-made component (which right now is virtually all of it) is, of course, caused primarily by the changes we ourselves are making to the atmosphere (which produces a cascade of secondary elements, too).