by Ann » Wed Jun 08, 2016 7:06 am
Chris Peterson wrote:Ann wrote:Venus has been extremely neglected by human-made probes. Considering how close it is to us, and how similar it is to the Earth in size and mass, our lack of interest in our sister planet is even more remarkable. Rather than thinking of Venus as our sister planet, however, we seem to treat it as humanity's unpopular step sibling or step world, one we don't want to have much to do with.
It is very good that the Japanese probe Akastuki is studying it.
Of course, it's good to study anything. That said, Venus is much less a "sister planet" than Mars, despite being more physically similar in a very broad sense. And it's very difficult to study- so many modalities are ineffective from space, and landers or rovers are essentially impossible, outside of very brief, sacrificial missions. And dynamically, it's harder to get to the inner planets than the outer ones. So for all these reasons, it's pretty easy to see why the focus has been on Mars for understanding terrestrial planets, and of course on the gas giants for the rest.
The fact that it is harder to get to the inner planets than to the outer ones is an important point.
Nevertheless, it seems to me that we are interested in Mars because Mars is sufficiently Earth-like that we might just maybe, maybe find life there. Venus, on the other hand, has such a scorching and stifling atmosphere that we can be (almost) a hundred per cent certain that there is no life there. And that is the main reason why we couldn't care less.
Personally I think that Venus is interesting precisely because it is
so inhospitable. It is far hotter than it "should" be, for example. How did it get that way? And what are the chances that exoplanets that might otherwise be habitable may have exprerienced similar runaway greenhouse effects?
Finally, is there anything that Venus can teach us about climate change, anything that might have any bearing on the situation here on Earth?
My impression (and please contradict me if you you think I'm wrong) is that NASA would much rather spend money on a "success story" like Mars than on the grim reality of Venus, even though the study of Venus might just possibly teach us some hard lessons about the Earth.
Ann
[quote="Chris Peterson"][quote="Ann"]Venus has been extremely neglected by human-made probes. Considering how close it is to us, and how similar it is to the Earth in size and mass, our lack of interest in our sister planet is even more remarkable. Rather than thinking of Venus as our sister planet, however, we seem to treat it as humanity's unpopular step sibling or step world, one we don't want to have much to do with.
It is very good that the Japanese probe Akastuki is studying it.[/quote]
Of course, it's good to study anything. That said, Venus is much less a "sister planet" than Mars, despite being more physically similar in a very broad sense. And it's very difficult to study- so many modalities are ineffective from space, and landers or rovers are essentially impossible, outside of very brief, sacrificial missions. And dynamically, it's harder to get to the inner planets than the outer ones. So for all these reasons, it's pretty easy to see why the focus has been on Mars for understanding terrestrial planets, and of course on the gas giants for the rest.[/quote]
The fact that it is harder to get to the inner planets than to the outer ones is an important point.
Nevertheless, it seems to me that we are interested in Mars because Mars is sufficiently Earth-like that we might just maybe, maybe find life there. Venus, on the other hand, has such a scorching and stifling atmosphere that we can be (almost) a hundred per cent certain that there is no life there. And that is the main reason why we couldn't care less.
Personally I think that Venus is interesting precisely because it is [i][b]so[/b][/i] inhospitable. It is far hotter than it "should" be, for example. How did it get that way? And what are the chances that exoplanets that might otherwise be habitable may have exprerienced similar runaway greenhouse effects?
Finally, is there anything that Venus can teach us about climate change, anything that might have any bearing on the situation here on Earth?
My impression (and please contradict me if you you think I'm wrong) is that NASA would much rather spend money on a "success story" like Mars than on the grim reality of Venus, even though the study of Venus might just possibly teach us some hard lessons about the Earth.
Ann