First Direct Photo of Exoplanet Confirmed

An anonymous reader noted a report confirming the first ever exoplanet actually photographed from telescopes on earth. Every other exoplanet so far 'observed' has been done by measuring wobbles of stars pulled by planetary gravity. But this one is a photograph. And that's just plain cool.

Re:Adaptic optics FTW

[eldavojohn]

I see this as a big triumph of adaptic optics. This picture was not made by a space telescope, but by an earth-based one!

Indeed, hope the liquid mirror option becomes practical and viable [slashdot.org] so we can achieve more amazing photographs and data like this. Although I have to wonder why they didn't use an orbiting satellite like Hubble to avoid Earth's atmosphere when photographing such an amazing thing. Have terrestrial adaptive optic solutions already caught up with orbiting satellites?

Re:Because we can't see Venus at night....

[Buggz]

Is there some weird definition of "Alien" that I dont know of?

Usually it means extra-terrestrial, but in this case they mean extra-solar (a word also used in the article). I'll assume the guy who came up with the headline is not the guy who wrote the article.

Re:Because we can't see Venus at night....

[Anonymous Coward]

"Extra-solar" planet is implied, dj smiley. I have been observing other planets with the naked eye for decades now...

Re:Aint the first

[yakumo.unr]

From TFA "first ever directly photographed by telescopes on Earth" Formalhaut_b was imaged from Hubble.

Other Direct Images of Exoplanets Exist

[rwllama]

There are several direct images of exoplanets available. Hubble took one of a planet around Fomalhaut, which was announced the same day that Keck announced three planets around HR 8799 (Nov 13, 2008). The next week, ESO announced a possible planet around Beta Pictoris, which has recently been confirmed. What these folks at Gemini are saying is that they announced a possible direct image earlier in 2008, which they have now confirmed, so theirs was really the first. It is a game of "who got the first direct image of a planet around another star?". It doesn't really matter, but it is very cool that we can now directly see not only the 8 planets in our solar system, but also at least 6 more in other solar systems. At some pivotal point in the near future we will have more pictures of planets outside our solar system than within it!

Who writes this stuff?

[joeyblades]

> first ever alien planet actually photographed...

Well, technically this is not the first alien planet photographed. That honor would probably go to Venus. However, this is the first exoplanet ever photographed, but it's old news since the first photographs of Fomalhaut's planet were taken in 2008...

Slow news day or something???

Re:Adaptic optics FTW

[rwllama]

Adaptive optics works great at infrared wavelengths. It does not (yet) do well at visible wavelengths. Even the 2.5 meter mirror of Hubble has better resolution at visible wavelengths than the 10 meter Keck mirror due to atmospheric blurring. Further, adaptive optics is only effective over small fields of view (such as a single star and planet). One can not take a wide field view of a nebula or a galaxy and get a high resolution adaptive optics view over the whole field.

Re:How big a telescope do we need to see cities?

[rwllama]

OK - Here's the math ...

100 light-years = 1 quadrillion kilometers -- You want a 1 meter resolution at that distance, so you need an angular resolution alpha, where tan(alpha) = 1 / 10^18 --> alpha = 5.7 x 10^-17 degrees

Let's use Hubble as a scaling proxy. It has a 2.5 meter mirror and 1/20th of an arc second resolution. Converting units, that resolution is 1 / (20*60*60) = 1.4 x 10^-5 degrees. Now, simply scale to get the desired resolution and you have the diameter of the mirror = 2.5 * 1.4 x 10^-5 / 5.7 x 10^-17

The diameter you want is 614 million kilometers, or more than 4 times the distance between Earth and the Sun. Good luck building that.

This submission is inaccurate

[The Bad Astronomer]

OK folks, this submission is pretty misleading about a lot of stuff. Here's the real poop (get the details on my blog [discovermagazine.com]):

In 2005, a planet was directly imaged orbiting a brown dwarf. That's not a sun-like star, but it was the first direct image of an exoplanet.

In 2008, it was announced that Hubble spotted a planet orbiting Fomalhaut. That's a star hotter and more massive than the Sun, but still sun-like. The images were taken in 2004 and 2006 and it took a while to make sure they were right.

However, those were taken from space. Also in 2008 images were taken of planets orbiting the sun-like star HR8799 using the ground-based Gemini telescope in Hawaii.

With me so far? The news today is from observations also taken in 2008, also taken by the Gemini 'scope (and a few months before the ones I just mentioned of HR8799). At the time, the planet was not confirmed. New observations indicate it is, in fact, a planet.

So to be completely accurate: the image from 2008 of a now-confirmed planet was the first direct image of a planet orbiting a sun-like star taken using a ground-based telescope. This is still very cool, but has been reported inaccurately (the space.com headline, for example, is wrong or at best incomplete).

Also, going back to the submitted text here to slashdot, planets have been found by three methods: the gravitation tug-of-war Doppler method, the transit method, and by gravitational lensing. I'll leave it up to you to look all that up; I'm exhausted. :)