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Quadrillian
Decades ago, there was lively and valid speculation about the existence of other civilisations in space. Though this speculation had it's roots in the fiction of the day it was nevertheless a legitimate line of enquiry. However this speculation was handicapped by lack of data, and soon took a euphoric turn. Now that the data is in thanks to millions of years of computer time in SETI's search, and from the results of the Kepler mission, it has been found that the most elegant and beautifully simple explanation of the Fermi paradox is that life is confined to Earth. We are alone. One of the great challenges of our time is to fathom why people so desperately need to fantasise about space aliens, despite total lack of evidence for their existence. Like others, I seek the answers to these questions. Original and intelligent discussion and contrary opinion is welcome. YA policy will be enforced in all correspondence.
How many cosmic dust particles hit Voyager in a million years?
OK folks, inspired by a recent question here, can anyone estimate how many cosmic dust particles will hit a Voyager spacecraft in a million years.
My estimate is 200 billion, which is about 60,000 per square millimetre on the leading surface. Quite a sandblasting!
Based on the wiki article on cosmic dust, voyager moving at about 16,000 kmph and a diameter of a metre or so.
Any advances on that figure?
3 個解答Astronomy & Space3 年前Anyone here feel all optimistic about space technology suddenly taking off like a rocket?
Good reasons (apart from getting off on it):
1) Fundamental Science has hit a brick wall. We spent billions on the LHC and all it does is confirms the standard model and pops up a Higgs particle. This is typical of the trend. The cost of science has now exceeded benefits. Ironically science itself is constrained by thermodynamics and the complexity is constraining any further developments. Not that I expect this to be widely appreciated here in the land where cliches rule over reason, but the upshot is that there are no more "new fundamental sciences" to come. Hence no new
space technology.
8 個解答Astronomy & Space4 年前Is anyone here familiar with the ETP model of oil and it's consequences?
Here is a brief summary:
http://www.thehillsgroup.org/depletion2_022.htm
There is some heavy science and economics involved. The consequences are profound, but the difficulty of the theory means that it is not readily accessible. I see this as a very high risk, like an approaching cyclone that noone can see coming.
1 個解答Other - Environment4 年前Why is microsoft so desperate to get us on Windows 10?
Most times I switch on the computer I'm asked if I want to install it. No I don't. I'm perfectly happy with Windows 7. Why the constant urging to upgrade?
6 個解答Software6 年前Why can't Superman be "ethnic" for a more interesting movie?
The superman movies are still being ground out of the movie factories. Personaly I can't see much incentive to ever go see them. It's bound to be the same corny old stories with the same conservative middle-america superhero.
So I was thinking, why can't superman be "ethnic". Why can't we have a movie where he is Jewish, or Muslim, or Chinese for example.
Best of all he could be Irish. He would dress in orange and green instead of blue and white. He would also fly feet first so he can land directly on his feet without having to summersault.
I might then even be tempted to go see the movie.
Cheers!
5 個解答Movies8 年前Mars outcrops breccia instead of conglomerate? Water not needed?
NASA is claiming that it has found conglomerates on Mars based on some deposits that have been found by the new Curiosity Mars rover. They are using this claim to go on to assert that water must have flowed across the planet, despite the current atmospheric conditions precluding water.
Couldn't those outcrops be more plausibly consist of breccia whose exposed clasts have been rounded remove their original angular morphology so the exposed examples resemble pebbles?
The breccias could plausibly have been deposited during volcanic eruption or be due to impact shock from ancient asteroid strikes (Mars is close to the asteroid belt, and there is ample evidence of volcanism on Mars). Hence there is no need to claim a watery past for Mars.
See this article for example (including images):
2 個解答Earth Sciences & Geology9 年前Curiosity safely on Mars. How's that!?
Well done to NASA. Didn't think they'd get away with it, but they did. Whos' looking forward to the first images?
6 個解答Astronomy & Space9 年前Could it be that there was never water on Mars?
Take a look at the latest images from the Dawn mission at the asteroid Vesta:
http://dawn.jpl.nasa.gov/multimedia/imageoftheday/...
Look carefully into the Oppia crater. Notice the flow channels starting high in the crater then broadening out towards the base. Notice how they look identical to the same flow channels that we are shown in images from Mars.
The same channels on Mars are the primary evidence that Mars had/has running water. Yet these channels on Vesta could not possibly have been made by water. They are caused by dust and debris falling downhill.
Could it be that Mars is dry now and always was? Is "water on Mars" just another variant of the "canals on Mars" fiasco from over a century ago?
8 個解答Astronomy & Space9 年前Anyone want to share the good news regarding Fobos-Grunt?
Now for some REAL science. tentative contact has been established with Russia's Fobos-Grunt mission. Read about it here:
http://www.esa.int/SPECIALS/Operations/SEM4NEZW5VG...
http://www.universetoday.com/91239/contact-establi...
Lets hope this mission can be rescued.
2 個解答Astronomy & Space10 年前What are legitimate reasons to believe there may be life outside Earth's biosphere?
OK, I confess I am pretty conversant with this topic so I know all about the "all the stars", "size of the universe","we exist so they must", and Drake equation type arguments. I am hoping to find some truly original or deeply technical reasons why we might expect other biosystems to exist. Is there anything I have overlooked? Any thoughts?
4 個解答Biology1 十年前Why do people believe in space aliens?
Considering that there is no scientific evidence for their existence it is hard to understand why people would believe such a thing. Any thoughts?
15 個解答Psychology1 十年前