From “Rocky exoplanet milestone in hunt for Earth-like worlds” (Jason Palmer, BBC News, 10 January 11), we learn,
Astronomers have discovered the smallest planet outside our Solar System, and the first that is undoubtedly rocky like Earth.
Measurements of unprecedented precision have shown that the planet, Kepler 10b, has a diameter 1.4 times that of Earth, and a mass 4.6 times higher.
However, because it orbits its host star so closely, the planet could not harbour life.
The discovery has been hailed as “among the most profound in human history”.
One can’t help wondering why, actually. Well, because
“We want to know if we’re alone in the galaxy, simply put – and this is one link in the chain toward getting to that objective.
“First we need to know if planets that could potentially harbour life are common, and we don’t know if that’s true – that’s what Kepler is aiming to do.”
Okay, but can we please leave the “most profounds” (the phrase is used twice in a short report) out for now?
Otherwise, what phrases will we haveleft when we find an extrasolar planet that can host life?
While we are at it, the phrase “a planetary missing link”, used in the story, doesn’t really work. If the conv-
|NASA artist’s conception of Kepler 10b|
entional explanation of planet formation is correct, Kepler 10b isn’t a long-sought link between one planet and another. And if we do find a planet that harbours life, it won’t be a link either – any more than Earth is a “link” between Venus and Mars.
A friend parses it all as follows,
We had total failure at finding Earth-like planets that might support our Darwinian assumption (and massive expenditure) that we are not unique in the universe. But now we’ve found something other than a giant-gas planet so we are less discouraged than before. But it turned out to be a solid chunk of iron at 1300 degrees orbiting a few solar radii above the star, so it isn’t what we were looking for, which is discouraging again. But we’ll call it “rocky” anyway and maybe our luck will return.
One hopes so. A summer planet would be nice. But not that one.