Astronomers discover an Earth-like planet
Wednesday, 22 April , 2009 18:38:00
Reporter: Richard Lindell interviewing with Ms. Lisa Millar
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. 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: 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. Now more than 350 have been found and today’s discovery of a planet around the earth’s size 21 light years away is pushing the limits of technology.
For that reason Professor Fred Watson is both excited and cautious about this latest find.
FRED WATSON: You have to remember that observations like these are extremely difficult to make and in particular when you’re pushing your equipment down to the level of trying to find things that are about the mass of the earth, then you really are looking almost in the noise of the information that’s coming back to you. So, it’s something that we have to at least remain, not sceptical about, but remain in some level of doubt.
RICHARD LINDELL: It’s hoped new discoveries will be much easier to make with the Kepler space telescope launched by NASA last year. Its mission is to find 20 such planets over the next five years.
LISA MILLAR: Richard Lindell.
Me: Wow, I truly didn’t think I’d see the day where we might have actually found a earth like planet witin my own lifetime. Yet here we are, it truly is a remarkable world we live in despite the problems we still currently face on a daily basis.
Here is the 2nd Related Video to LaMB by Simple Plan.