Friday 24 February 2017

Exoplanet discovery: Five facts you need to know about Nasa’s new solar system | The Independent


Plenty of stories about the seven planets discovered around the nearby (40 light years) "super cool dwarf" star Trappist-1. Three of them may be habitable.
Google did a Doodle...
The story in The Independent is one of the best. Be sure to click on the internally-linked ESO video "what could the planets look like?".
According to the Cambridge University astronomer Amaury Triaud "The spectacle would be beautiful because every once in a while you would see another planet in the sky bigger than the moon".
The sky would be salmon-pinkish (my favorite!)
The dwarf star Trappist-1 is going to last trillions of years, 700 times longer than our own sun and "longer than the life of the universe" according to this article. (Though I don't quite get how that could be...).
I've often hoped we would find, in my lifetime, evidence of life elsewhere in the universe. In a poll at this article, 75% of people think we may do so in "our lifetime". We may just do it and soonish.
Should we send a probe to Trappist-1? After all, it's "only" 40 light years away.
I did the calculation. The fastest man-made object is the Juno Jupiter Explorer which was slingshot out of earth orbit in 2013, then accelerated by Jupiter's gravity to 210,000 km per hour. That's 1,839,600,000 km per year.
Trappist-1 is 378 Trillion km away. So it would take Juno 205,000 years to get there (round about...).
I guess we'd best just watch its dim-beautiful light for now. Apparently it would be like a salmon-pink sunset on earth, but with the sun much larger in the sky. And sister planets would look twice the size of our moon.
More exciting news may come next year when the James Webb telescope will take over from the venerable Hubble. It can look at the three likely planets, Trappist 1-e, 1-f and 1-g, the three in the habitable zone, and see if there are traces of nitrogen, carbon dioxide, ozone or methane, all markers of life.
Can't wait!
LATER: how nice that this comes as we learn that Churchill wondered about life in the universe outside our solar system, in a recently found essay. It receives much praise, for being clear headed and scientific.