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View Full Version : SETI Has Already Tried Listening to TRAPPIST-1 for Aliens



Fraser
2017-Feb-25, 08:41 PM
Ever since the presence of exoplanets was announced in the TRAPPIST-1 system, SETI has been monitoring the system for signs of alien life.
The post SETI Has Already Tried Listening to TRAPPIST-1 for Aliens (http://www.universetoday.com/133782/seti-already-tried-listening-trappist-1-aliens/) appeared first on Universe Today (http://www.universetoday.com).


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bknight
2017-Feb-25, 09:21 PM
Our best spacecraft could take you to Mars in 6 months. To shuttle between neighboring Trappist planets would be a weekend junket.
LOL of course it will take ~500,000 years to reach any of them from Earth.

Spacedude
2017-Feb-26, 01:49 PM
Ever since the presence of exoplanets was announced in the TRAPPIST-1 system, SETI has been monitoring the system for signs of alien life.

The star is said to be young ("at least 500 million YO "), are they expecting to find colonizers from another system? Is there a better estimate of Trappist-1 age?

01101001
2017-Feb-26, 02:52 PM
Key words: "at least".

NASA: Earth-sized planets: The newest, weirdest generation (https://exoplanets.nasa.gov/news/1416/earth-sized-planets-the-newest-weirdest-generation/)


The exact age of the TRAPPIST-1 star is unknown, but scientists believe it is at least 500 million years old [...]

Where did you hear its age constrained to be "young"? And what does "young" mean for an ultracool dwarf?

Spacedude
2017-Feb-26, 04:31 PM
Where did you hear its age constrained to be "young"? And what does "young" mean for an ultracool dwarf?

"Young" is my interpretation of "at least 500 myo". I'd like to know if there's an "at most" age estimate. 500 myo is basically a newborn for an ultracool dwarf.

01101001
2017-Feb-26, 04:57 PM
OK. Yeah, it is young, in a sense.

Wikipedia: Ultra-cool dwarf (https://en.wikipedia.org/wiki/Ultra-cool_dwarf)


As the age of the universe is "only" 13.8 billion years, all cool dwarf stars are relatively young.

There's no reason to think it is still near its minimum age of half a billion years.

It could be much older than the Sun.

KaiYeves
2017-Feb-26, 05:25 PM
LOL of course it will take ~500,000 years to reach any of them from Earth.

They mean if one of those planets was our home and not Earth. It's a hypothetical.

Ross 54
2017-Feb-26, 05:38 PM
Yes, it's difficult to determine the age of M dwarf stars. The metallicity, which gives some indication of the star's age. is poorly constrained here. (Z=0.04 plus or minus 0.08).
Star systems with terrestrial planets have been forming in our galaxy for at least 11 billion years. If TRAPPIST-1 were only 500 million years old' it would be ~ 6 per cent of the possible age of such a system. Likely to be much older, which is obviously why it seemed a worthy SETI target.