Today, Spitzer Space Telescope announced the first direct detection of a planetary object. Go infrared astronomy 
!
http://www.spitzer.caltech.edu/Media/releases/ssc2005-09/release.shtml
Here is an “image” of the planets:
This is cool for a couple of reasons (although not the huge breakthrough news media are making it out to be). Until now extrasolar planets have been primarily detected by two methods. The first is by measuring the radial velocity of the parent star’s orbit, due to the gravitational tug of the planet. The second is by measuring the dimming of the light of the star, due to the planet’s movement in front of the star.
The technique used in this case is to actually detect the dimming of the star as the planet moves behind it and so directly be able to infer the planet’s brightness.
I have the bad feeling however, (and reading the Slashdot comments on this story gave me confirmation), that many people still get confused what we mean by “detecting” the planets. I fear that in people’s heads there are pretty pictures floating around with planets orbiting stars. In reality we cannot actually resolve the orbits of the planets and will not be able to for quite some time. Oh and on a last note, Spitzer didn’t actually discover these planets, they were previously discovered by transits.
And now some really geeky links:
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