To find life in space scientists look for planets with conditions similar to earth. New calculations made by Penn State researcher Ravi Kopparapu reveal that their may be more of these types of planets than we previously thought. If we just look at the 10 nearest small stars, we would find at least 4 potentially habitable planets. Scientist look at M-dwarf stars to try to find these planets because they are more common than stars like our sun. The new calculations predict there to be about 3 times as many potently habitable planets than previously thought. That's good news if you are searching for extraterrestrial life.
Link:
http://www.sciencedaily.com/releases/2013/03/130312152047.htm
Themes of NoS:
- Science is tentative; new calculations can be made when new data becomes available
- Science is collaborative; Kopparapu worked with many people to develop his model
The article said they were looking for planets the same size as Earth, but they didn't explain why. Wouldn't a larger or smaller planet be just as habitable as an Earth-sized one if it was the right distance from its star?
ReplyDeleteWith new possibly habitable planets being found, scientists need a good way to find out if life exists on them. using polarized light, i.e. light reflected from a planet is different from the light a star gives off, scientists can determine if the surface is land or water, how much, how cloudy it is, and it is even possible to detect the biosignature of chlorophyll.
ReplyDeleteIn response it Julia Robinson, Earth-sized planets are better then larger or smaller because gravity is a huge part in life, too much and they would die, too little and they would float around and lighter gases may escape the atmosphere. Also Earth-sized planets are the only known size of planets to contain life, so it will quicken the pace to find life, if it exists, to look for planets with similar conditions as Earth.
http://www.dvice.com/archives/2012/03/new-spectral-te.php
I always find it curious that scientists search specifically for planets similar to Earth in order to find planets that may potentially contain life. I can understand the logic in it. We are more likely to detect life that is similar to life on Earth. But we've already seen that even on Earth, there is a wide variation of environments where life can exist.
ReplyDeleteIn response to Julia's question, I also agree with Nick's gravity response. But again, after the hypothetical of discovering life on other planets, it seems likely that we may also discover life in all sorts of new extremes. Even the storms of Jupiter could potentially contain a microbe that doesn't need the same things that life on Earth does.