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First Earth-Sized Exoplanet May Have Been Found
Adam Korbitz writes "New Scientist is reporting the extrasolar planet MOA-2007-BLG-192Lb — whose discovery was announced just last summer — may actually be the first truly Earth-sized exoplanet to be identified. A new analysis suggests the planet weighs less than half the original estimate of 3.3 Earth masses; the new estimate pegs the planet's size at 1.4 Earth masses. The planet orbits a small red dwarf star, some 3,000 light-years from here, at an orbital distance of 0.62 astronomical units, about the same distance as Venus from our sun. One significance of the planet's discovery is that it points to the probable ubiquity of smaller terrestrial planets in somewhat Earth-like orbits around red dwarf stars, the oldest and most numerous stars in the galaxy. Here is a video report from the discoverers."
MOA-2007-BLG-192Lb ain't LV-426. If you know what I mean...
Sig this!
Why don't we figure out how inhabit to Venus and Mars first, and then look for things farther away? At 3000 light years, it's a bit too far to think of starting a settlement there.
Just because it's an earth-sized planet doesn't mean it's Earth-like. Red dwarf stars are very small (no more than half the mass of the Sun). They don't put out much energy so the habitable zones are very small and very close to the planet. Being so close to the sun makes it likely that the planet would be tidally locked (same side always facing the sun) which isn't so good for life. Finally red dwarf stars often have high stellar variation (sometimes fry you, sometimes freeze you), also not so good for life.
So exciting, but keep looking.....
http://en.wikipedia.org/wiki/Habitability_of_red_dwarf_systems
If you are familiar with the work of Charlie Lineweaver's group in AU, you would be aware that not only should Earth-like planets exist but that a significant number of them are older, and potentially more advanced than we are. This might then lead you to explore whether or not Matrioshka Brains (forms of civilizations significantly more advanced that our own exist.) And indirectly to an understanding that extremely advanced stellar civilizations have very different heat signatures (or detection signatures) from our own. Thus the detection of an earth-like planet is not that significant. The detection of a star going dark, signaling a civilization making a Kardashev-Type-I to a Kardashev-Type-II transition -- now that would be interesting.
Since the strength of the gravitational field of a planet is a factor of its mass, and the gravitational pull on the surface is in direct relation to the distance from the center of the planet... could it not be possible to have a planet the size of say, Neptune, with a geological makeup similar to the Earth, that has a lower mass and therefore the acceleration at the surface is exactly 1g (as we understand it here on Earth). That is within the bounds of physics, is it not?
Or maybe the effective gravity is stronger, but the planet spins faster. Faster days as well?
The problem I guess would be the existence of a formation process that actually creates a planet with such a large surface but happens to be mostly rock instead of mostly gas (supposedly gas giants are "failed stars"). If it has a molten iron core, would it not collapse in on itself?
Interesting, imagine a planet with the surface composition and atmosphere of Earth (and supposedly biomass) but 10 or more times the surface. That would be amazing.
Make sure you put velcro on your tool bag - they've been known to float away.
I record my sleeptalking
I'm used to size meaning volume...
Otherwise you might say a bullet is the size of 100 feathers...
3000 light years means that we are seeing it as it was 3000 years ago. If you could get to the speed of light right now, it would be 3000 years until you got there (assuming that the relative distance between us is roughly constant). But you can't go that fast, you'd have to go a lot slower than that.
In the next 3000 years we are sure to develop much faster methods of travel, so will will overtake you (i'll wave as we pass) and when you get there all the hot alien babes will be taken.
I want to see video of the planet.
I want to delete my account but Slashdot doesn't allow it.
This got me thinking:
If inhabitants there invented faster-than-light space travel, and arrived on Earth thousands of years ago. Eventually their civilization was destroyed by some freak natural disasters and all techs were lost.
We are just their descendants, now looking at our home planet?
Virtual Betting on Facebook for non-geeks.
The problem isn't Earth - its humanity. And if we do get out there, we'll break that too.
No need for any new technologies. Just stop fucking with the existing systems, wind the population down to 10m and enjoy. This is Eden and to not get that is very sad. The very concept of "it needs improving" is why we are so fucked today. See http://www.kansascity.com/news/world/story/986910.html
Not necessarily. The problem is the "unthinking" masses of humanity. We have it really easy on Earth compared to the artificial environments that we would need to sustain ourselves in space. First we'll have to figure out a long-term approach for how to reliably protect our reproductive organs from ambient high-energy radiation once away from the Earth's magnetic field so that independent colonies don't get overwhelmed by birth defects. Eventually though, living in space would apply a whole new set of evolutionary pressures for survival and human space-farers would have to adapt. If we survive long enough to permanently colonize space, it would probably transform that part of humanity that would make it into space by making it much more aware of risk evaluation and risk taking, and general incompetence will get weeded out fairly quickly and ruthlessly by the ambient dangers of space.
It might take a few failed colonies at first, but eventually a society would evolve a way to ensure that happens. Perhaps mandatory civil service that involves external colony maintenance as a requirement for political office? Or maybe even the same for obtaining the voting franchise - a sort of Starship Troopers lite.
In fact, if you were a space-going race you probably wouldn't want to establish contact with a species that hadn't already gone through that winnowing out process. I would even go so far as to say that that difference might eventually lead to true divergence of humans into two species: the earth-bound and the space-faring.
If "we" get out there, the people that colonize another planet probably won't be the same "people" that are messing up Earth right now because those people wouldn't survive long enough to make it that far. Yeah, it's kind of an elitist view, but evolution is the ultimate meritocracy and, in very harsh environments, the people that forget that don't stay in the gene pool long.
Laissez lire, et laissez danser; ces deux amusements ne feront jamais de mal au monde. - Voltaire
On the flip side, the spin-off technologies from making a sustainable habitat off planet would probably do wonders for improving the quality of life on planet.
If the spin-off technologies are so valuable, why not fund the research, skip making the actual trip, and wind up with better technology without going anywhere? Do everything except build the final vehicle and we save lots money and get cool technology.