Spotted on the BBC News website: A story about the discovery of an earth-like (or at least more Earth-like than Jupiter-like) planet in the “Goldilocks” zone of a star a mere 20 light years or so away!
The planet orbits the faint star Gliese 581, which is 20.5 light-years away in the constellation Libra.
Scientists made the discovery using the Eso 3.6m Telescope in Chile.
They say the benign temperatures on the planet mean any water there could exist in liquid form, and this raises the chances it could also harbour life.
“We have estimated that the mean temperature of this ’super-Earth’ lies between 0 and 40 degrees Celsius, and water would thus be liquid,” explained Stephane Udry of the Geneva Observatory, lead author of the scientific paper reporting the result.
“Moreover, its radius should be only 1.5 times the Earth’s radius, and models predict that the planet should be either rocky - like our Earth - or covered with oceans.”
Reading a bit further on:
The exoplanet - as astronomers call planets around a star other than the Sun - is the smallest yet found, and completes a full orbit of its parent star in just 13 days.
Indeed, it is 14 times closer to its star than the Earth is to our Sun.
However, given that the host star is smaller and colder than the Sun - and thus less luminous - the planet nevertheless lies in the “habitable zone”, the region around a star where water could be liquid.
To make their discovery, researchers used a very sensitive instrument that can measure tiny changes in the velocity of a star as it experiences the gravitational tug of a nearby planet.
This is quite exciting, although I do wish that they’d clarify the use of “life” to the more cautious “life as we know it”, or “as far as we understand”, but I always have that gripe about such articles.
Read more here on the BBC, and here on AP (via Yahoo).
-cvj
(Thanks Oliver!)
Some Related Asymptotia Posts (not exhaustive):
Lovely. Isn’t it odd how commonplace stories like this are which would have been the realm of the fantastic just a few years ago?
Personally, I’m still waiting for the detection of free oxygen in the atmosphere of a planet orbiting another star. I’m thinking it will happen sooner than we dare think.
Someone’s updated the wikipedia already!
The star is a red dwarf, which is the most common form of star.
Standing under alien trees, feeling rather heavy. I look up at a swollen red orb in the sky, full of gloomy spots. A few days makes a year here so not long ’til my 1,320 birthday, how nice!
Maybe tho, I should wait for some spectroscopic oxygen first
Ha! If their year is 13 of our days, I wonder how long a day there is? What would it be like to be a civilization growing up in a place where the day and the year were almost the same amount of time? The seasons would sure seem a lot less important…
Uh oh… wait a minute! If their day were really long, like 12 Earth days, that could be trouble. I’d hate to live on a planet that got beaten by the sun 169 (?) Earth days in a row. There is such a thing as too much sunshine!
Someone at Bad Astronomy asked how long it would take to get there, so I ran through the relativistic rocket calculations. At 1g shipboard acceleration, unless I made an arithmetic mistake, you’d spend 3.6 years ship time getting there (if you didn’t bother to slow down to visit) and about 20.5 years Earth time.
Another planet to move to, once our sun becomes a red giant?
At 1g shipboard acceleration, unless I made an arithmetic mistake, you’d spend 3.6 years ship time getting there (if you didn’t bother to slow down to visit) and about 20.5 years Earth time.
Hmmm… I’m not the adventurous type, and unfortunately your numbers don’t look so good for an automated mission. 40 years to get there plus 20 years to get the postcards back is kind of a long time… most of the people who worked on the project would be dead before any interesting signals made it back. Not to mention the enormous energy needed to maintain a 1g acceleration for 20 light years, and the difficulty of programming a robot to fly 20 light years and then explore an uncharted solar system without any human guidance!!! Oh well… there’s always our own solar system…
Ugh! The energy problem is worse than I thought… naively calculating the work required to accelerate a (constant-mass) 2000 kg spacecraft at 1 g over 20 light years by just multiplying gives around 4*10^21 joules, or about 40,000 kg of fuel converted entirely to energy! Even if that number is an order of magnitude too high, it’s still completely ridiculous for a 2000 kg ship.
But maybe the relativistic calculation is much different…
Oh, come on, there must be all sorts of humanoids walking around who really are aliens from that planet; because, well you know, they have advanced technologies and have been ‘watching” and “among” us for a long time. All we need to do is just ask, right?
Is life not as we know it really life? According to whom?
Professor Johnson or anyone else who is good at this,
if the space ship traveled very fast and experienced time contraction, would it still be 20 years of their time to take the trip?
-Andy
Andy — according to Blake Stacey, above, anyone aboard the ship would enjoy a short, 3.6-year trip.
So do we beam messages that way? We could get a reply in 41 years. I might live that long.
The paper mentions missions to the star. They’re talking about near space telescopes to study it.
Current tech is Voyager I. At that speed, it’s about 370,000 years, one way. We could do better if we tried harder. Perhaps solar photon or electric sails, better Juptier assist, etc.
According to the Mayan calendar, which dates back thousands of years and predicted all previous major changes in societal mindsets, we will meet our ancestral neighbours in 2011-can’t wait!
Great! This is just after (according to Bladerunner) everyone will have flying cars in LA, which I’m also looking forward to a lot!
-cvj
Flying cars! Where’s my Jetpack? C’mon, physicists, let’s get going with these avionic ideas; I’ve got places to go….
it would bw nice if we could know the much more information than we have right now. i cant wait to get more surprised.:-)
its really foolish we (human being)should not be commit to surprised