New planet discovered in Milky Way

CNET ^ | Wed Jan 25 | Stefanie Olsen

[lmr]

Astronomers usually detect them by watching how they make their parent star wiggle, a technique known as the Doppler method.

These planets aren't actually seen, they are 'detected' by the gravitational forces that are present in a system. These planets are hence 'inferred' to be there. Could there be other things causing the 'wobble" like other stars or black holes or something?

[El Gato]

How is this "more Earth-like" than anyone discovered before?

The others have all been much larger planets. Many a lot larger than Jupiter. If they were a little bigger, they'd be stars in their own right. Most of the discoveries of extra solar planets have relied on techniques which measure the effect of the planet on it's parent star. Since it takes a big planet to move a star in a measurable way, only large planets have been discovered.

Most of those planets have been quite close to the parent star as well, also due to the one of the techniques for detecting them, so they've been HOT as well as HUGE.

[El Gato]

These planets are hence 'inferred' to be there. Could there be other things causing the 'wobble" like other stars or black holes or something?

"Or something" perhaps. Black holes, unless truly tiny, would make their presence known in other ways, although there cases of multiple star systems where one of the "stars" is actually a black hole. Other stars would also be "visible", or at least their spectrum would be.

Basically, if it's considerably lighter than a star, and isn't glowing, then it's a planet, almost by definition.

[sheik yerbouty]

Metaluna?