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Finding Twin Earths Is Harder Than We Thought
Matt_dk writes "Does a twin Earth exist somewhere in our galaxy? Astronomers are getting closer and closer to finding an Earth-sized planet in an Earth-like orbit. NASA's Kepler spacecraft just launched to find such worlds. Once the search succeeds, the next questions driving research will be: Is that planet habitable? Does it have an Earth-like atmosphere? Answering those questions will not be easy. 'We'll have to be really lucky to decipher an Earth-like planet's atmosphere during a transit event so that we can tell it is Earth-like,' said Kaltenegger. 'We will need to add up many transits to do so — hundreds of them, even for stars as close as 20 light-years away.'" The abstract of their paper offers a link to the complete paper as a 17-page PDF; here is a short description from 2007 of the same researchers' work, outlining the type of spectral signature that an Earth-like atmosphere would be expected to show.
Build in a FTL drive and have Starbuck magically... oh fuck it.. what a cop out. :\
that it will take hundreds of years to tell if they are truly Earth-like. And that is complete nonsense.
Once we find a sufficient collection of candidate planets using this instrument, we can devise a different device/experiment to narrow down whether they are Earth-like. That should take maybe a few years to ten years.
That is more-or-less the pattern we have been following, and it has been successful so far. I see no reason to change.
There's an important distinction between it being hard to find an earthlike planet, and there not being an earthlike planet to find at all.
Our mechanisms for finding planets are all in wobbles in the wavelengths from the light of stars. And because of that, we tend to only see the big wobbles, because small wobbles tend to get lost in the noise.
It would be nice if we could shine a flashlight and get a real look out there, but in most cases, we'd never see what we shone light upon in our lifetimes.
The universe is a HUGE freakin place, filled mostly with stuff we can't get a good clear look at yet.
Entire worlds like ours are are both all we know, but at the same time, are too small for us to even notice in the grandness just outside our atmospheric window.
Ryan Fenton
I'm fairly certain that the little green men, ticked off after years of being depicted as scrawny, bug-eyed, space-faring bobbleheads, will just come in rayguns blazing, but the machines, prizing efficiency and precision above our human failings, would probably arrive and play muzak with a pre-recorded voiceover telling us that our death is important, and would we please wait.
Is being blasted into your component molecules by unimaginably powerful energy beams really more distressing than being put on hold?
Blank until
Of course, it will only be possible to tell if it was Earth-like X number of years ago. Since there are only a few stars within 100 light years, X will usually be more than 100. In the meantime, there could have been a planet killing asteroid, or an advanced civilization could have nuked itself. So, we can only really find "twin Earths" from the past. We'll never actually know what it's like until we go there...
...actually, even that's not true, in the sense that "we" means everybody on Earth. Only the travelers will know it's true. Earthlings will have to wait for the return trip or signal, to tell them that it *was* true. Even then, for most stars it would be your great-great-great.... children receiving the signal.
Bottom line? The Universe's speed limit sucks. Where's the fuzzbuster?
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
I don't think the idea is to find a new place for us to live. Obviously, our ability to take advantage of such a planet is incredibly limited.
Rather, its to understand what the possibilities for life outside our planet are. Putting it in simplest terms, its working to get experimental data for some of the coefficients in the Drake equation.
We don't have the technology for any type of hibernation space travel now, which is why I think its so important to follow these types of research. Even if it takes 100000 years to travel to a new planet, that's pittance compared to what it took for current level sentient life to develop on Earth.
Second, even if they did, how in the world do you conclude that would be "less distressing"?? One does not follow from the other.
Well, duh. If they have advanced AI, they probably have internet as well. Which means we can view alien porn while we're being wiped out.
According to theories of what the earth's atmosphere was like before life flourished, the atmosphere was full of CO2 and nitrogen. There was no oxygen. According to our understanding of the earth 4 billion yrs ago, the earth would be a VERY different place today if there were no life here because oxygen is a byproduct of photosynthetic life. I theorize that the moment we find a planet like ours, we will have found life on another planet.
Bullets hurt people because of human blood circulation (loss of blood) and the size of our organs (heh). If robots were built differently or little green men evolved differently, bullets would most likely be ineffective. There is no reason that there is only one wire connecting processor to leg and opening one loop should not hurt the other parts of the circuit. Also, there is almost no reason why the processor needs to be 15 cm big, or the leg motor has to take up the whole length of the leg. There is also no reason why the robots or green guys have to be human size.
However, as long as they are still made of molecules, high amounts of energy should still be able to separate the molecules that they are composed of, and hopefully eliminate them.