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Giant Planet Nine Times the Mass of Jupiter Found
cremeglace writes "In the late 1990s, astronomers noticed a distinct warp in the disk of dust and gas orbiting a young star some 60 light-years from Earth. Now, using new analytical tools, researchers have discovered a giant planet lurking within the dusty haze. About nine times as massive as Jupiter and composed mainly of gas, the planet is only a few million years old, proving that such enormous planetary bodies can form rapidly."
What's amazing about this is that the images taken of the star clearly show the planet first on one side of the star, and then the other, several years later.
FWIW, mass isn't the story here; we know of hundreds of planets in that mass range. I would say the story is that two images taken a few years apart show the planet's motion, and that Beta Pic, the parent star, was the first to have a disk seen around it back in the 1980s. This planet explains the warp and other features in the disk, too, that have been known for years! I wrote about this on my Bad Astronomy blog.
*** Phil Plait, aka The Bad Astronomer http://www.badastronomy.com
What's amazing isn't that the planet is orbiting it's parent star, it's the technology to take a picture of the planet and be able to see it moving over time. Most extrasolar planets aren't detected this way, they usually use either Doppler shift or reduction in brightness to detect the existence of a planet and extrapolate from there. There's only a handful of examples of optically sighted extrasolar planets, and this is the first I've heard of having two pictures of the same system, both with the planet visible.
Not only is that 'cool' but it allows us to start cataloging planets that orbit their stars on a plane perpendicular to the direction we are viewing them. Previously, a planet had to conveniently be orbiting such that we were looking into the system edge on. The real excitement will come when we can view terrestrial planets this way with enough resolution to perform spectrographic analysis on the atmosphere and search for, among other things, sings of life.
The universe is a pretty big place, or so I have been told. Undoubtedly if you look long enough you will find entities that challenge your preconceived label or definition of what something "IS". In a universal sense, everything is in flux, so all we are really doing is classification of temporal slices that we can deal with in our limited capacity. At exactly what point does a X become a Y? Considering the time frame being measured is so long, and our perspective so short, it becomes a point of debate, depending on what you call one thing in terms of the other.
So to summarize:
If it shines it's a star.
Else if the mass is greater than the theoretical minimum for fusion (13 Jupiter masses), it is a brown dwarf.
Else if the mass orbits a star or stellar remnant it is a planet
Else it is a 'sub-brown dwarf'