First suspected in 1993, now confirmed: There's about 2.3 Jupiter mass planet orbiting the orange giant star Pollux (Beta Geminorum). The planet orbits the star at a distance of 1.64 AU in a circular orbit.

It is the first known planet around a first magnitude star.

See the Extrasolar Planets Encyclopaedia entry.

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Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

There's a dirty joke in this somewhere, but I just can't see it.

Is the link right? Shouldn't the star be named Pollux, not given a directory name?

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Wikipedia: A MMORPG for self-denialists.

It's gotten to the point where careful investigation is needed just to tell parody from reality. I think that means reality is broken.- Noclevername.

HD 62509 = Beta Geminorum = Pollux

Astronomers don't usually use proper names of the star, often not even Bayer designations.

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Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

Well that's pretty darn cool. Question for the experts:

Does being of Jupiter mass mean that it has to be a gas giant?

Are there reasons a Jupiter size planet could not be like Earth?

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Don of Borg - Cool, Calm, Collective.

"Within the next generation I believe that the world's leaders will discover that infant conditioning and narco-hypnosis are more efficient, as instruments of government, than clubs and prisons, and that the lust for power can be just as completely satisfied by suggesting people into loving their servitude as by flogging them and kicking them into obedience." -- Aldous Huxley

Yes. When a protoplanet is massive enough, hydrogen and helium cannot escape from it. It is nearly impossible that the planet doesn't accrete surrounding hydrogen and helium into it. Even the "hot Jupiters" that orbit very close their stars have thick hydrogen atmospheres. If gas giants can form from disk instabilities, there may be planets that don't even have solid cores of heavier elements.

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Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

That is awesome. Gives me a nice nostalgic thrill thinking of all those sci-fi stories and novels set around prominent bright stars. I never expected to see something like this, at least not so soon.

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"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

--The State

Next time I set up I'll have to give it a look instead of just using it for an alignment star.

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You're a coward and a liar and a thOOF - Bart Sibrel

Maybe they should name the planet Hallux.

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"What you think you thought you saw you did not see." Agent J, MiB - Manhatten Bureau

Following the links I just discovered that Arcturus is also known as Alpha Boo.

I think if I get a puppy I'm going to call it Beta Boo.

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Wikipedia: A MMORPG for self-denialists.

It's gotten to the point where careful investigation is needed just to tell parody from reality. I think that means reality is broken.- Noclevername.

Yes, from "Alpha Bootis" (or "Alpha Boötis", the two o's are spelled the latin way).

Ah! I'm getting inspired...I'm going to catch up with the infamous Star Registry, and have my friends, Dick & Jane, buy a star and name it SPOT.
Pete.

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A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

Would it be possible for a Jovian moon to be in captured rotation on the dark side of the planet--some distance away--so that the gas giant always appears as an occultor and blocks some of the light--so that the gas giant is always between the moon and that big star?

In other words, can a moon's orbital period exactly equal the planet's orbital period?

Possible, but it would have to be a truly mind-bending coincidence. Unlike tide-locked rotation, there is no process that would force a moon into such configuration. And even by some miracle it did happen, it would not last very long. A very small perturbation would make the moon's orbit slightly longer or shorter -- and instead of spending all its time in the shadow, it would spend months or years in the light followed by months or years in the shadow.

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Fiction has to be plausible. Reality is under no such constraint.

Well, our sun and moon appear nearly the same size--and we have found planets which orbit in different directions--so it might not be such a stretch that an object might be shielded--be in a perpetual eclipse--and perhaps have life--otherwise it would be too hot for a life-giving Jovian moon of the more usual sort described elsewhere here, correct?

Could it be a binary Jovian?

I see the home page shows 194 exoplanets. 200 is coming fast. :clap"

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

A hypothetical moon of Pollux b could not stay permanently in its shadow. Pollux b (a.k.a. HD 62509 b) has an orbital period of 589 days around Pollux;

in order to remain in the shadow of this planet, a moon would need to have an orbital period of 589 days around HD 62509 b also. But this would make the orbit of the moon so wide that it would be outside the planet's Hill sphere; the moon would not be in a stable orbit but would wander away to become a planet in its own right.

Alternately the moon could orbit the Lagrange 2 point, behind the planet- but in this case the moon would not be close enough to remain in shadow all the time, and anyway the l2 point isn't stable in the long term.

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