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Mars & The Teachable Moment
Gallenod writes "In this article at space.com, Edna DeVore, Director of Education and Public Outreach for SETI, states that people are being continually exposed to pseudo-science from watching television and reading tabloids. Her examples include the "face" on Mars (which she discusses in detail in the article), alien autopsies, Area 51 in the Nevada desert as alien storage quarters, the "non-landings" on the Moon, UFO's, and alien kidnappings. DeVore describes the current Mars missions as a "teachable moment," an opportunity to teach factual science and astronomy in the context of sensationalistic psuedo-science and the legion of money-grubbing opportunists who make their living churning it out."
There's a great book by Carl Sagan that talks about his perspective on Pseudo-Science and how it's affecting Science, as well as the dangers. It's a wonderful read. The book is called The Demon Haunted World: Science as a Candle in the Dark. I highly recommend it to anyone interested in this topic.
Life today. Uncertainty tomorrow.
There aren't any canals. The "belief" that there were canals on Mars, carrying water was an artifact of the relatively poor resolving power of the telescopes of the day, and the human mind's desire to find patterns. It's virtually the same process behind the claims of the "Mars face".
Current science says that it would be extremely unlikely that you would find liquid water, on the surface of Mars given it's current conditions (temperature, pressure).
Evidence found by the Rovers indicates that at some point in Mars past, there was likely a standing body of water, probably a highly saline "ocean".
These statements are not contradicting each other.
No. There is absolutely NO evidence for that, and it's not even physically possible for it to have happened.
badastronomy.com has an execelent debunking of that rediculous claim and many others.
Okay... I'll bite:
ask yourself how the shadow on the moon is produced while it goes through one "monthly" cycle and how the sun and the earth are involved.
Sun, Earth, and Moon are all, more or less, orbiting each other in nearly the same plane. The moon moves around the Earth roughly once every 28 days or so. When the moon moves to be furthest from the sun (instead of the Earth), the light reflects off of it and comes back to us on Earth, giving us Full Moon. When it moves closest to the sun, we can't see it because all the light from the sun hits the side away from us and thus isn't reflected to the Earth, and thus we get New Moon. What's so hard to understand about that?
ask yourself how the seasons come into being and what role the precession of the earth axis plays in combination with the sun
The Earth is tilted at an angle from its plane of orbit around the sun. This angle is what gives us seasons. Considered from the Northern Hemisphere, during the months of roughly June to August, it's summer. Summer means that the angle of the earth's rotation combined with its position in orbit about the Sun puts the Northern Hemisphere more directly under the sun at noon. The difference is only that of a couple hundred miles or so, compared to winter, but that's enough. The seasons get reversed in the southern hemisphere because it's on the opposite side, obviously.
Precession is the fact that, like a top, the Earth's rotation angle rotates around a circle, describing a cone if you consider the motion of the line along the axis of rotation. After a large amount of time (millions of years), the Earth will have precessed enough to, essentially, move the times in it's orbit that coincide with the seasons. And thus the seasons, slowly, gradually, move along the calendar year. After a long time, the seasons will have rotated and the southern hemisphere will get summer in June-August instead of from Dec-Feb like it does now.
Again, what's so hard to understand about that? Every schoolchild should have learned these things. I did, in like 2nd or 3rd grade.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
For the sake of argument, let's assume that it is possible to read license plates from space. The angular size of the numbers on a license plate (~1 inch) as viewed from low Earth orbit (~200 mi) is on the order of about 1e-7 radians.
The closest approch of Mars to Earth in the last fifty thousand years was about thirty-five million miles. Assuming the same angular resolution, that same telescope pointed at Mars should be able to resolve details about five miles across under absolutely ideal conditions.
In practice, the idea that satellites can read license plates is a myth. See here.
To actually read license plates, you'd need to put something like the Keck telescope in orbit--and ten-meter scopes don't generally fly well. Even then, you can't get great pictures of Mars. The only way to get high-resolution photographs of Mars is to send a probe there and take pictures from Mars orbit--which is exactly what NASA has been doing. So far, there hasn't been anything which suggests more than microbial life on Mars, and even that's still very much an open question. We do know there aren't obvious large-scale features of civilization--dams, highways, walls, skyscrapers.~Idarubicin