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Hubble Snaps Photo of Extrasolar Planet
iamlucky13 writes "Space.com has reported that a Hubble Space Telescope photo supports with a very high degree of confidence that a picture taken by the European Space Observatory does indeed show an extrasolar planet. As many readers know, planets outside our solar system are typically found by watching for wobbles in a star's orbit or for dimming caused by the planet crossing in front of its star. The ESO and Hubble images would represent the 1st and 2nd times that planets outside our solar system have been directly detected. The planet is about 5 times as massive as Jupiter and orbits a brown dwarf a little farther out than Pluto orbits our own sun."
The ESO is the European Southern Observatory, not Space Observatory.
NASA is developing the Terrestrial Planet Finder which should discover and image even smaller extrasolar planets when it is launched in a few years. Sooner than that, the Kepler Mission "will survey the extended solar neighborhood to detect and characterize hundreds of terrestrial and larger planets in or near the "habitable zone," defined by scientists as the distance from a star where liquid water can exist on a planet's surface."
The MSNBC cites the space.com article as its source, and the space.com article states:
"It orbits the brown dwarf star at about 30 percent farther than Pluto is from our Sun."
It was easier to see BECAUSE it goes around a brown dwarf. A brown dwarf has the mass to be a sun but not enough "feul" to create the fission reaction to light up. So essentially it is easier to see because there is not as much light around it. That and the fact that it is such a large planet. While 5 time Jupiter's size seems large, there are suns that are as big as the entire ORBIT of Jupiter in diameter. So as planets go, yes its big, but not sun-like in size.
This is the kind of silliness that results when astronomers talk to the press.
Among ourselves, astronomers will talk about how many "sigma" a detection is, referring to how far above the Gaussian noise the signal is. A 1-sigma detection is real 68% of the time. 2-sigma detections are real 95% of the time, 3-sigma data are 99.7% sure, etc. So, Glenn is just saying that the hypothesis that the brown dwarf and its candidate companion are actually moving together in space is supported by the data above the errors by about 2.5 sigma or so. With further observations, the errors will shrink, and it will then be above three sigma (assuming the hypothesis is correct).
But, Glenn can't talk about "sigmas" to the press, because, sadly, not everyone knows the wonders of the Gaussian normal distribution. So he does a quick conversion to probabilities for the press release. BTW, it is indeed possible to characterize errors to the tenth of a percent, especially when you are close to 100% confidence.
Get ready for more astronomy-related news this week; our annual society meeting (AAS) is taking place in San Diego.
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
"2 butted 2048 × 4096, 15 m/pixel CCD detectors"
So it is 16MP for the wide field camera, less for others.
With our current technology, the largest extra-solar planets are the only ones we can reliably detect, let alone photograph.
It helped significantly in this case that the planet was so far away from a dim star, because most of the difficulty comes when searching for a dim speck in the glare of a bright star. The December National Geographic had a great article on the search for extra-solar planets and compared it to finding a firefly in the glare of a lighthouse from several miles away.
Thus, astronomers have not ruled out the possibility of planets in nearby systems. In fact there are already a few hundred that have been found, but only by detecting the "wobble" of the sun as others here have pointed out. This is the first to be directly imaged.
As technology and methods continue to improve we will be able to detect smaller and smaller planets, closer and closer to their suns. The smallest currently detected is around 14 times the size of Earth (roughly the size of Neptune, I believe).
Once we can regularly detect Earth-sized planets in life-sustaining orbits, astronomers hope to be able to detect hints of the planets' compositions using the spectrums of light emitted (can't remember the exact terminology off-hand).
Anyway, for those of us familiar with astronomy and astrobiology, this is very exciting. And to put it into perspective, this image is of even better resolution than we had of Pluto until just a few years ago.
Yes, IAAAA (I am an amateur astronomer).
If I may say so, life is a game, and there's so much to do and so few turns.
-Reiner Knizia
We're bouncing bloody lasers off the stuff they left there. What kind of proof people really need to believe we've landed?