Most Earthlike Planet Yet Found May Have Liquid Oceans

Astronomers discover an Earth-like planet

Wednesday, 22 April , 2009 18:38:00
Reporter: Richard Lindell
LISA MILLAR: The Holy Grail of astronomy is to find a planet capable of supporting life.

European researchers have taken a big step forward in that quest, discovering a planet just twice the size of the Earth.

And while this planet is too hot to sustain life, astronomers speculate that another larger one orbiting around the same star could contain water and perhaps even some form of alien life.

Richard Lindell reports.

RICHARD LINDELL: At 21 light years away, the discovery of a planet almost as small as the Earth is a big deal.

Stephane Udry is one of the astronomers at Geneva University that made the discovery.

STEPHANE UDRY: It's a huge step forward. The lightest planet before was more than four Earth masses, now we are below two Earth masses. It demonstrates that we can find Earth mass planets.

RICHARD LINDELL: On a more fundamental level, it also demonstrates that Earth-like planets actually exist outside the solar system.

But Gliese 581e orbits too close to its star to support life.

It's a different story for another much larger planet orbiting around the same star.

Professor Fred Watson is the astronomer-in-charge of the Anglo-Australian Observatory near Coonabarabran in New South Wales.

FRED WATSON: Gliese 581d, which was found about two years ago, is probably within the star's habitable zone, which some of us call the 'Goldilocks zone' because it's that region around a star where the temperature is not too hot and it's not too cold but it's just right for liquid water to exist.

So, it is possible that if Gliese 581d has rocky surface, that there may be liquid water on that surface and that would make it, as we understand it today, that would make it habitable.

RICHARD LINDELL: But it's not universally agreed that a rocky surface is needed to support life.

Professor Paul Francis at the Australian National University.

PAUL FRANCIS: Some people think it might be a liquid planet entirely covered in ocean many hundreds of kilometres deep. And so in principal it might be quite a pleasant place with liquid water and waves and maybe even some sort of marine life forms.

RICHARD LINDELL: Associate Professor Peter Tuthill at the University of Sydney says the discovery is remarkable but falls short of the Holy Grail.

PETER TUTHILL: They've found one planet that fits the mass criteria and around the same star, quite remarkably, they've found a second planet which is at the right radius, but to win the big prize you would want both of these things to happen at same time.

RICHARD LINDELL: But the planet hunters have come a long way in a short space of time.

The first planet outside the solar system was discovered just 15 years ago.

More: http://www.abc.net.au/pm/content/2008/s2549990.htm

---

Near Neighbor

Gliese 581, a red dwarf star in the constellation Libra, lies around 20.5 light-years from Earth.

"In astronomical terms it is one of our near neighbors, the 87th closest known star system to the sun," said Carole Haswell, an astronomer at the Open University in Milton Keynes, U.K.

Since planets orbiting Gliese 581 are too far away to be seen directly, Mayor and colleagues originally spotted Gliese 581d by searching for tiny wobbles in the host star's motion using the European Southern Observatory (ESO) telescope at La Silla in Chile.

Weighing in at around seven Earth masses, Gliese 581d is unlikely to be made of rocks alone, the team believes.

"We can only speculate at this stage, but it may have a rocky core, encased in an icy layer, with a liquid ocean at the surface and an atmosphere," Mayor said.

Meanwhile, the much smaller and lighter Gliese 581e "probably doesn't look too different to Earth, except that it will be very hot, because it is so close to its host star," said Andrew Norton, an astronomer also at the Open University.

Norton's colleague Haswell added: "It is very exciting that such a promising candidate for an Earthlike planet has been found so close to us. It means there are likely to be many more when we search further."

And the more Earthlike planets there are, the greater the chance of discovering one that harbors life.

"I think it is only a matter of time," Norton said. "If life really does exist elsewhere in the universe, then within the next 10 to 15 years I expect we may see the first signs of life, via spectroscopic signals from exoplanets."

More: http://news.nationalgeographic.com/news/2009/04/090421-most-earthlike-planet....

Category:

Education

Tags:

• Gliese
• 581d
• Most
• Earthlike
• Planet
• Yet
• Found
• May
• Have
• Liquid
• Oceans

[EyesOnTheSkies]

It's definitely a possibility thanks for the comment.

[bangNL94]

It would be funny if there were people on that other planet watching us, and thinking the same about us :P

[duteen]

I really dun wanna find life I wanna find another planet that we can also live on so that if anything may happen to earth we can send people to the other planet befor the disater arises

[bangNL94]

@ThePooper3000 Funny, how I said that two years ago, and it's still in the top rated comments. Though now I think that the word "funny" is totally out place here.

It's fascinating to think that there could be other species out there on other planets, some may be much more civilized than ours, but others who would look a lot like we did 100,000 years ago. Any of those could be looking up to the sky and think: "What if there is other life out there?".

[ThePooper3000]

@duteen Or we could bring another Earth-like planet to our solar system and have 'em right beside us just like neighbours

[ThePooper3000]

@bangNL94 I say that to self every day

[GardenHillislandlake]

@MrFarhanAhmed79 lmao, highly unlikely, the government would just try and assimulate them

[MrFarhanAhmed79]

what if we may have peacful relationships with other planet people...

[Gabe69Velasquez]

I refer to Wikipedia only because of limited space here, I don't trust Wikipedia myself, BUT their articles are made using REFERENCES, published papers written by scientists and teams of scientists. Wikipedia is not my maid sources. ALSO, I can do the MATH myself, I know from the facts Gl 581 c gets MORE heat than VENUS.

[bangNL94]

I'm not trying to argue with you about that, but Wikipedia should not be your main source of information.

^^

[lizwilder123]

ha ha yes it would be real funny. i always think that.

[lizwilder123]

we should make mars better for life before zooming off to a planet so many light years away... at least then we can save our butts before earth goes kaboom. Mars will get better... it HAS to. it's like... the most possible place for life, even if it's -40 degrees celcius, but then... the north pole is.