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Trio of Super-Earths Discovered
FiReaNGeL writes "A group of astronomers have now discovered a system of three super-Earths around a rather normal star, which is slightly less massive than our Sun, and is located 42 light-years away towards the southern Doradus and Pictor constellations. 'We have made very precise measurements of the velocity of the star HD 40307 over the last five years, which clearly reveal the presence of three planets.' The planets, having 4.2, 6.7, and 9.4 times the mass of the Earth, orbit the star with periods of 4.3, 9.6, and 20.4 days, respectively. 'The perturbations induced by the planets are really tiny — the mass of the smallest planets is one hundred thousand times smaller than that of the star — and only the high sensitivity of HARPS made it possible to detect them' says co-author François Bouchy, from the Institut d'Astrophysique de Paris, France. Clearly these planets are only the tip of the iceberg."
a super-earth? It is a bigger planet with Earth-like atmosphere, or it this just a bad translation?
A short orbital period and a higher mass mean a greater possibility we can see the star shifting back and forth as the planet revolves around it. As our instrumentation and measurements get more accurate and precise we should be able to reliably infer the presence of smaller planets with longer orbital periods.
With how many large planets we're finding, it's pretty likely there are plenty of smaller earth like planets to be found when we gain the ability to do so.
Even people that believe in pre-destiny look both ways before crossing the street.
Every time there's news of earth or super-earth sized planets, we always find that they're orbital period is like 5 days, which would mean the planet is completely scorched and incapable of supporting life or bearing liquid water. Such a downer....it doesn't matter what sized planet you have if its orbit places it so close to the star. Is this because the whole eclipse-detection method requires the planet to be close to its star so we can't actually detect planets further out from the star? I'm actually kind of tired hearing about "exciting" new of another planet being discover 5-30 million km from its star...that is not even close to being in the habitable zone people.
What exactly makes these Earth-like? From the data it appears that their masses are several times greater than Earth and their orbital periods are much much shorter than Earth. Is it because the star they orbit is similar to Sol? Is there any indication of water or an atmosphere on any of them? Not that this isn't a cool find, but it seems that the use of the word "Earth" is just sensationalism. I would've been just as happy if they had simply said "three planets."
God, schmod. I want my monkey man!
Oil is NOT a fossil fuel, it is ABIOTIC
Not really, since it depends on your point of view. For the inhabitants of the planet with a orbital period of 20.4 days, Sol is about 750 lightyears away, and the third rock has an orbital period of nearly 18 years.
Whose suprised? The first few planets last decade were suprises, because there was a real debate as to how rare planetary systems were. Now that we know they are common, its long expected that we will find Earth mass planets - the only question is when. The real suprises are coming when we look at overall systems (no one expected to find Jupiter+ massed planets in close orbits), or when we look at the atmospheres.