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Billions of Planets In Milky Way?
jeffsenter writes, "The Washington Post has the story: 'NASA scientists using the Hubble Space Telescope have discovered what they believe are 16 new planets deep in the Milky Way, leading them to conclude there are probably billions of planets spread throughout the galaxy.' What sets these potential planets apart is they are in the central bulge of the Milky Way where most stars are located. More planets in the galaxy means more chances for life." The 16 are planet candidates at this point, until verified by spectroscopic measurement of their parent stars' wobbles, which probably can't be done until the James Webb Space Telescope files in 2013.
This is a great example of a ground-based telescope that could easily rival any space telescope:
OWL Telescope
Yeah I used the life angle to get it posted, but there is a little bit of substance to this increased chance of life thinking. Even though the central bulge is not the best place to find life, finding plenty of planets in the central bulge, where large scale planet formation was somewhat in question, suggests that planets are formed around stars everywhere, not just in our galactic neighborhood. If planets are formed everywhere as opposed to just in select parts of the galaxy there are more planets generally and planets present in parts of the galaxy that are more hospitable to the formation of life.
It is not just the area of the galaxy around earth that has planets. Planets are probably helpful for the formation of life. More planets more chances for life.
The article said these findings were based on 7 days of observations, using the transit method. In this method, the planet passes in front of the star, causing a very small, but sudden and periodic drop in the brightness of the star. Presumably, they don't claim to have a candidate unless they see multiple dimming events. If so, the longest possible orbit they could have observed is 7 days, meaning the planets are extremely close to their stars. Even their moons would be inhospitable.
However, as another poster pointed out, these systems may also harbor smaller planets in more favorable orbits. In fact, some researchers believe that smaller rocky worlds can only form with the assistance of disturbances created by the gas giants.
In contrast, other researchers are skeptical that planets can form at all in the inner regions of the galaxy because of the high star density. Even if they did, they might not be able to harbor life because of all the radiation from said stars.
As another poster pointed out, however, we don't necessarily know the limits of conditions that life may form. This is getting a rather fanciful, but perhaps high-temperature silicon-based rock monsters are real, like Season 4, episode 7 where Kirk fought the lava man with the Abe Lincoln avatar (just kidding, I made that up...or did I?).
Assuming we don't kill ourselves before our sun fails catastrophically:
What remains to be determined are:
So from this, a good guess might be 1/1700 of the rocky planets out there are habitable. If our solar system is typical, we have 5 rocky planets, so there would be a (1 - (1699/1700)*(1699/1700)*(1699/1700)*(1699/1700)*(1 699/1700)) or chance of our solar system evolving any life at all, or about 0.29%. Multiply times the odds of a habitable planet having intelligent life at any given time (about 1/2), and we have about a 0.145% chance (only a little better than 1/1000) of finding intelligent life in a solar system with rocky planets.
Nowhere near the 1 in a million long shot speculated, but this assumes that Earth is typical, which is not necessarily a valid assumption.
Check out my sci-fi/humor trilogy at PatriotsBooks.
There's a theory that no lifeform will evolve to become significantly more intelligent or technologically advanced than humans, because at the level of intelligence we've reached an increase doesn't offer us an evolutionary advantage. We're already able to survive and breed, and indeed dominate the planet. And as a society gets more advanced in terms of technology, its members require less and less intelligence to survive and breed. This will eventually lead to a slow decay in intelligence which slows or stops the technological advance as well. The species will ultimately end up in some kind of a permanent, static equilibrium state if it survives long enough. We may be just a couple of centuries away from this ourselves.
Spinning liquids to form mirrors works on Earth because Earth's gravity acts perpendicular to the plane of spin. We would need some way of replicating those two forces in space. All the methods I know about would cost more than simply launching a solid mirror.
A method of putting cheap mirrors into space that I proposed to my physics mentor a few decades ago is to use inflatable mirrors. He brushed off the idea at the time. Now, though, NASA has research on the general concept:
NASA Tech: Parabolic Membrane-Thickness Variation for Inflatable Mirror
A Google search for inflatable mirrors turns up many more results.
Taking stuff apart since 1969 (TM)