Universe Today again
Posted on April 11th, 2008 by blue collar scientistThis is a little disheartening. Universe Today has repeated erroneous reports that the smallest exoplanet so far has recently been found. Citing a Reuters story - not the best place to learn astronomy facts - the same UT contributor who posted the bizarre story about the Sumerian Aten asteroid “impact” reports:
The planet has a mass five times the size of Earth, which makes it the smallest extrasolar planet among the roughly 300 identified so far….
As far as I can determine, from a quick look through the Interactive Extra-solar Planets Catalog, the smallest exoplanets found to date orbit PSR B1257+12, a pulsar 980 light years away in the spring constellation Virgo, and they were discovered eighteen years ago. The planets orbiting that star have masses of 0.02, 3.9, and 4.3 Earth masses. The Reuters story talks about how Spanish astronomers found an exoplanet of 5 Earth masses. Which is two hundred fifty times bigger than the smallest pulsar planet!
It must be time for the funding cycle at CSIC Research Institute, where the PI announcing the discovery is based.
I don’t mean to pick on Universe Today. I read them religiously, and they rarely do this kind of stuff. This is an aberration, a statistical anomaly, an edge case. They usually get it right. Don’t hate them.
Tags: exoplanet, exoplanets, not the smallest
April 13th, 2008 at 3:44 pm
I think most readers understood that they were talking about the smallest planet of a sun-like star, which a 5 Earth-mass body may or may not be (some others announced in recent years came close); those weird pulsar planets are in a different ballpark and quite usually ignored in ‘classical exoplanetology’.
The real error here is that this news isn’t news at all: The actual paper had been on the preprint server since January which nowadays constitutes a publication.
April 14th, 2008 at 2:24 am
In light of these new discoveries, the smallest planet of a sun-like star would be Mercury, wouldn’t it? Call me old-fashioned, but I always thought that if someone meant “smallest exoplanet of a sun-like star,” the phrase “sun-like star” could be used to alleviate the confusion that would otherwise result from just saying “smallest exoplanet.” The claims being promoted are simply false.
And I’m not certain it is true that the pulsar planets are “usually ignored” in “classical exoplanetology,” if there is such a thing, given how widely the initial papers on them are cited according to ADS - in papers about orbital dynamics, proplyds, planetary formation, exoplanet transits, and other topics I know little about.