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NASA's Kepler Discovers Multiple Planets Orbiting a Pair of Stars
DevotedSkeptic writes "Kepler has continued its stellar (pun intended) discovery spree, this time locating multiple planets orbiting a binary star system. This is especially interesting because it proves that more than one planet can form under the stresses of a binary star system. The system is known as a circumbinary planetary system, a mechanism where a planet orbits two stars. Prior to this discovery, having multiple planets in a circumbinary system was unproven. Named Kepler-47, the system consists of a pair of orbiting stars that eclipse each other every 7.5 days. One star is similar in size to our Sol, however it only provides approximately 84% of Sol's light, the other is smaller, measuring one third of the size of Sol and emits less than 1% of Sol's light. Kepler-47b is the closer planet to its two suns, orbiting in 50 Earth days. Kepler-47c is further out and orbits every 303 days, within the Goldilocks zone. 'Unlike our sun, many stars are part of multiple-star systems where two or more stars orbit one another. The question always has been — do they have planets and planetary systems? This Kepler discovery proves that they do,' said William Borucki, Kepler mission principal investigator at NASA's Ames Research Center in Moffett Field, Calif. 'In our search for habitable planets, we have found more opportunities for life to exist.'"
I just wanted to have the first Tattoine reference
"Pun Intended". Either people get it, or they don't. It's not clever if you have to point it out.
The Kruger Dunning explains most post on
"this time locating a multiple planets orbiting a Binary Stars"
w.t.f.?
-SaNo
Finds like this and the expansion of human knowledge continues to amaze me. Every. Single. Time.
More funding for science!
From TFA:
"The outer planet, Kepler-47c, orbits its host pair every 303 days, placing it in the so-called "habitable zone," the region in a planetary system where liquid water might exist on the surface of a planet. While not a world hospitable for life, Kepler-47c is thought to be a gaseous giant slightly larger than Neptune, where an atmosphere of thick bright water-vapor clouds might exist."
Wouldn't this cause some bizarre tidal forces too? IANAP, but seems that the relative masses of these bodies might lead to a excentric orbit that would push Kepler-47c into and out of the habitable zone.
a [sic] multiple planets orbiting a [sic] B[sic]inary S[sic]tars.
Really? I'll give the submitter the benefit of the doubt because English may not be their first language, but isn't this what we have editors for?
Kepler-47b is closer to its two suns orbiting in 50 Earth days.
Err, closer than what? Kepler-47a, I'm going to assume. No, I'm not going to RTFA. We are Slashdotters!
systemd is Roko's Basilisk.
If you read this headline, the brighter star contributes 84% of the light, the dimmer star 1%. 84 + 1 = 85%, not the total 100.
If you read the linked through article, it says the brighter star is 84% as bright AS our Sun, and the dimmer star 1% as bright As our Sun.
Sigh
That would make for some interesting tides and seasons.
Ok, this writer clearly isn't a scientist. They say that 84% of the light of the system comes from the brighter star, and 1% from the dimmer. That's all the light, right?...84 + 1 != 100 If you read the original NASA article, they said the brighter star is 84% as bright as our Sun and the dimmer one 1% as bright as our Sun. *sigh*
Seems like a bit of a degenerate case to me. The two stars orbit each other each 7.5 days. I wouldn't be surprised if their atmospheres practically overlapped with that kind of distance. The planets essentially would be orbiting the center of mass of the two stars as a result. I wonder if they'd eventually merge, and what would happen then.
I think that this situation is likely to be a lot more stable than having another star orbiting further out than the planets.
With a period of just 7 days, you have to wonder how fast the little bugger is moving. Could be a significant fraction of C...?
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
binary star is not a proper noun unless you're talking about the old school hip hop group http://www.youtube.com/watch?v=okcRjRwFVLU
insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
... on Kleper-47c? 47c maybe is a gas giant, but may have many rocky or ocean moons.
Religion: The greatest weapon of mass destruction of all time
We only have one known planet where life has occurred and is sustained. There is no prof, yet, that life ever occurred on Mars or any other planet in our system. At this point with what we actually know about life I think the "habitable zone" graphics on some of these press releases are overly optimistic. I hope we can find evidence of life on Mars so we can actually expand our "known" habitable zone.
It all starts at 0
Unlike our sun, many stars are part of multiple-star systems
IIRC from my star fighter days, most stars, the vast majority of them, are part of multiple-star systems. Sol is very weird and a rare counter-example in that regard.
The Admin and the Engineer
Time to start looking for Smoke Rings http://en.wikipedia.org/wiki/The_Smoke_Ring_(novel)
>Prior to this discovery, having multiple planets in a circumbinary system was unproven
Ok when movies like Star Wars come out with visible advanced knowledge that such things do exist, either it leads me to believe that many humans on this earth are really aliens mascarading as us and enjoying lives of financial freedom due to the use of knowledge that no one else would know... George....I know u r really an alien and actually just brought your story from another galaxy where you came from as a regular story of what your life was like back there...
OR
That the probability that all things no matter how far fetched do exist, and at some point we might be run over by an army of goblins and ogres like in Lord of the rings...Gandalf might need to be brought out of his deep cryogenic freeze once again.... or wait was that Demolition Man...?
I always get them mixed up.... :(
NASA's Kepler Discovers Multiple Patents Orbiting a Pair of Stars?
ironic captcha: projects
This is the simplest case, but its conceivable to have stability with a star orbiting farther out as well. In the case like this one, you could maintain accretion disk formation with much larger star separations as long as the separations weren't so large that they cleared all the material, or introduced significant eddies / disturbances in the disk. To a point, simulations have actually shown that a little bit of this stirring helps. Solar orbit distances are also often vast compared to planetary orbit distances, so the other extreme can occur, where there can be an extensive internal band of stability between two distant companions; thereby allowing inner planets to form around each star. Hierarchical star systems of 3, 4, 5, ect.. stars would also potentially produce stable planets as long as they had large gaps between the centers of mass and outer orbit paths of each sub-system. http://en.wikipedia.org/wiki/Multiple_star#Hierarchical_systems for visualization of the hierarchical relationships.
A sparse multiple system with planets orbiting at least two of the stars. That would make for some good scifi for it would allow practical interstellar travel between the planets.
Just sayin'
Sounds like the Seefra system - I wonder if one of the suns is artificial?
Wake me up when they find habitable planets with six suns.
/ The Arrow
"How lovely you are. So lovely in my straightjacket..." - Nny
Instead of writing "Sol" all the time, how about . . . the sun? Do we really need to be so ashamed of the Germanic heritage of the English language that we won't even call the sun "the sun" in a scientific context? I can understand using the word "solar," since we have no other common adjectival version of the word "sun" . . . but "Sol"?