Venus Probe Returns First Images 154
The BBC reports on the first images returned from Venus by the EU probe. From the article: "They show the hothouse planet's south pole from a distance of 206,452km. Mission scientists are already intrigued by a dark 'vortex' feature which can be clearly seen in one image. Venus Express will orbit the planet for about 500 Earth days to study its atmosphere, which is thought to have undergone runaway greenhouse warming." They're offering some high-rez images of the planet at the ESA website.
A few high-res images? Well, it's a start... (Score:5, Interesting)
Re:Whoa (Score:2, Interesting)
The image I link to is a smaller gif image yet still contains much more clarity and detail than these deformed images.
They say first impressions count and the person who considered putting up these images instead of clear lower resolution ones needs a talking to.
Re:A few high-res images? Well, it's a start... (Score:3, Interesting)
Now, some would regard this outreach work as a waste of money, but it ignores the fact that exploration and research requires trained motivated persons, person who have been exposed to the subject since childhood. Persons who have seen exploration and research as an exciting and compelling profession. This means making the subject accesible to average children and thier parents.
NASA used to be much better at this. There was a time when one could get a much closer unsanitized look at the operations. The profit motive and corruption has limited those opportunities, and now visitors are limited to Theme Park representation of the Space Admninistration, involving misrepresentation of science and 20 year old movies.
In spite of all this, I stil give NASA more points for not forcing a click wrap license before every picture.
Re:Has to be green house gases (Score:5, Interesting)
You've got to be a true red Republican to deny the greenhouse effect on Venus.
If you do the math, since temperature goes as the 1/4 power of the recieved radiation and the recieved radiation goes as the square of the distance, with all else being equal 25% closer gets you about 15% hotter. In other words without a greenhouse effect venus would be about 45C hotter than earth.
If you put the Earth at the location of Venus, the oceans wouldn't boil. Not immediately at least. What would happen is that the evaporation rate would increase which would put more water vapor in the air. Since water vapor is a greenhouse gas that would increase the temperature which would evaporate more water. That's an example of positive feedback. Eventually it would get hot enough for the oceans to boil.
Without the oceans to absorb CO2 and without the life forms in the ocean which take CO2 and turn it into rocks, the CO2 released in volcanos (not to mention the forests catching on fire) stays in the atmosphere where it adds further to the greenhouse effect.
The CO2 and all the water vapor combine to form carbonic acid which increases the weathering of carbonate rocks releasing still more CO2. Meanwhile UV radiation (sunlight) in the upper atmosphere dissociates the water vapor into oxygen and hydrogen. Because it is light, the hydrogen escapes into space. The oxygen oxidizes any unoxidized materials on the surface. If any of those materials contain accessable carbon, you've just released more CO2 and increased the greenhouse effect.
Plate tectonics continues on for a while releasing more CO2 until the point where the water bearing minerals that enable plate tectonics on the Earth have disappeared. Plate tectonics stops. At this point you've got... you guessed it... Venus. Not that you'd be caring. You died long before the oceans started boiling.
This is what would absolutely happen to the Earth if we were to raise its temperature by 45C. What we don't know is where the dividing line is. Maybe it's 25C. Maybe it's 5C. And so we've decided to raise the temperature by 3C in the next 100 years or so.
The main difference between the Earth and Venus isn't the temperature. It's where the CO2 is. In Venus, it's in the atmosphere. On Earth, it's in the rocks. Pour some vinegar on some limestone if you don't think it can come out again. The oceans are already becoming acidic enough to cause difficulties for some shell building organisms....