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Comment Re:Update on this story (Score 1) 377

Dear Lover of 1984-Style Government (aka, a liberal):

I'm always amazed how distorted the political name-calling has gotten. White means black and black means white. From

From Old French liberal < Latin liberalis ("befitting a freeman") < liber ("free").

1. (now rare except in phrases) Pertaining to those arts and sciences whose study was considered "worthy of a free man" (as opposed to servile, mechanical); worthy, befitting a gentleman.

2. Generous, bountiful.

3. Generous in quantity, abundant.

4. (obsolete) Unrestrained, licentious.

5. Free from prejudice or narrow-mindedness; open-minded, open to new ideas, willing to depart from established opinions, conventions etc.; permissive.

6. (politics) Open to political or social changes and reforms in favour of increased freedom or democracy.

Comment Re:Plane (Score 1) 97

Yes, but we also know exactly what's the probability of detecting a planet in our plane of sight. The point of the Kepler mission is to examine hundreds of thousands of stars and determine which ones have planets and what kind of planets they are. Then using probability we can then extrapolate how many such planets exist around other stars (not in our plane of sight). The sample size is what makes this extrapolation valid.

Comment Re:Excellent (Score 1) 224

The energy required would probably be higher than what you could get out of the nuclear fuel. Remember: shooting something into the Sun doesn't cost zero energy. The Earth's orbital speed is about 30 km/s and there's no atmosphere to loose that velocity.

Comment Re:Serious question here ... (Score 1) 351

But all rockets work that way: you accelerate until all of the fuel is used up. Ion engines are not special in any way, they just take longer to use the fuel. However, that has no effect on the final result. Conceptually, it's really easy to understand. All reaction engines (including conventional rockets and ion engines) work by "throwing" some mass. The momentum of the lost mass provides thrust in the other direction. Since the thrust is the result of the change in momentum it depends only on two things: the mass which is lost and the velocity at which it is "thrown".

Comment Re:Serious question here ... (Score 1) 351

Ion engines don't have this constant velocity problem.

I don't know what you're talking about. If you have an unimpeded path through vacuum you're going to have a constant velocity.

Any self-propulsion system has exactly the same problems due to the limits imposed by the rocket equation. Basically, an ion engine can reach a higher velocity only because its exhaust velocity is much higher, but it's still far from practical for interstellar travel. For that you need to get your rocket to about 0.1c, which is practical only if your exhaust velocity is at least something like 2% of c or 6,000,000 m/s. The exhaust velocity of ion engines is only about 30,000 m/s.

Comment Re:Thats cheating (Score 1) 246

(Otherwise, somewhere 'outside' the observable universe, there is an infinite amount of storage available for each number needed, and some sort of mechanism that handles those calculations in what looks like finite time to any point of view inside the universe - congratulations, you've just proved both the omnipresence and the omnipotence of God - probably not what you were aiming to do).

Dude, I want some of that shit you're smoking!

Submission + - Oldest Known Tetrapod Found (

qazsedcft writes: The oldest footprints ever made by four-legged creatures have been discovered by scientists, forcing them to reconsider a critical period in evolution: the point at which fish crawled out of the water onto land to evolve into reptiles, mammals and eventually humans. The "hand" and "foot" prints are 18m years older than the earliest, previously confirmed fossil remains of "tetrapods" or four-legged vertebrates and were left by lizard-like creatures up to 2.5 metres long. The discovery, reported in tomorrow's issue of the journal Nature, was made in a former quarry in the Holy Cross Mountains in south-eastern Poland. The fossil footprints can be reliably dated to the early Middle Devonian period, around 395 million years ago.

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