Hat-p-1

[bg1256]

Hat-p-1

linky

I found this pretty interesting. It might be old news, but it's news to me.

HAT-P-1 is too far away to be imaged directly, but scientists know it is there because of the way light from its parent star dims as the planet passes in front.

This part intrigued me. I know squat about astronomy...does anyone know how they can know anything with confidence, when they can't even view it directly?

 

[Sokar Rostau]

Take a lightbulb and sweep your hand across it. See that shadow? That's how it works.

New planets aren't even news anymore. There's about 50 of them, all bigger than Saturn and most bigger than Jupiter. It's easy to find a planet that's 15 times the size of Jupiter...

 

[bg1256]

Take a lightbulb and sweep your hand across it. See that shadow? That's how it works.

New planets aren't even news anymore. There's about 50 of them, all bigger than Saturn and most bigger than Jupiter. It's easy to find a planet that's 15 times the size of Jupiter...

I was referring more to the density, etc. How do they know its density if they can't even see it? And they seem so confident too.

 

[Merick]

Well, to figure the density you need mass and size. I guess they can get the size by measuring the dimming of the star as it passes by. The mass I think can be derived from how far away it is from the sun, so they should be able to find that too by finding an how the light output of the star varies as it passes by.
Or so seems to make sense to me.

 

[Dondrei]

It's all pretty hazy guesswork. We really need to extend our baseline to get some more convincing data. Or better yet send actual probes.