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Two Planets Found Sharing One Orbit
dweezil-n0xad writes "Buried in the flood of data from the Kepler telescope is a planetary system unlike any seen before. Two of its apparent planets share the same orbit around their star. If the discovery is confirmed, it would bolster a theory that Earth once shared its orbit with a Mars-sized body that later crashed into it, resulting in the moon's formation."
Quick, we need to redefine the meaning of "planet" yet again.
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If the discovery is confirmed, it would bolster a theory that Earth once shared its orbit with a Mars-sized body ....'
To say nothing of confirming John Norman and the Tarnsman of Gor!
Great minds think alike; fools seldom differ.
That there's a duplicate Earth on the exact opposite side of the Sun!
First rule in government spending: why build one when you can have two at twice the price?
This is more liberal lies. Bill O'Reilly told me that you can't explain that!
What a fool believes, he sees, no wise man has the power to reason away.
I always assumed that Dantooine and Tatooine were twin planets like this. Or did that mean something else?
I swear to God...I swear to God! That is NOT how you treat your human!
That there's a duplicate Earth on the exact opposite side of the Sun!
OK, just for the fun of it: what would be the most efficient method to check this hypothesis?
By checking how its gravity would effect other planets in the same star system. For background: Counter-Earth on Wikipedia, Lagrangian point L3 on Wikipedia, and Counter-Earth on TV Tropes. Executive summary: We don't have one, and we know this because if we did, we'd be able to detect its pull. Furthermore, such an orbit would be unstable.
how is this amazing. there are an infinite amount of things in the skies... I wouldn't be surprised to see a new Galaxy that had an outline shaped like a Penis
Is there another Earth on the far side of the Sun orbiting every 365 days?, anyone check?
It's not clear that this is anything new. A number of astronomers have suggested that we should treat the Earth/Luna and Pluto/Charon pairs as "double planets" sharing an orbit. And there's a pair of Saturn's moons that share an orbit. Of course, whether these are counterexamples depends on the picky, legalistic details of how you define the term "planet", which we've discussed to death here on /. already. Fun as such pseudo-arguments may be, the fact is that they're not terribly significant.
Thus, for the Pluto/Charon pair, reclassifying Pluto as a "dwarf planet" make it especially an edge case, since it still includes the term "planet" in its classification. But they're both large, spherical bodies in a single orbit around the sun, while also orbiting each other.
The Earth/Luna pair is a bit of a mathematical curiosity. One of the arguments supporting calling our moon a "planet" orbiting the sun is that its orbit is everywhere convex with respect to the sun. You'd expect a "moon" to have a much more wiggly orbit, parts of which are curved away from the sun, and this is true of the other objects in the solar system that we call moons. OTOH, the barycenter of the Earth/Luna pair is (slightly) inside the Earth, which can be used with some definitions to say that it's really a satellite of the Earth.
And, of course, Saturn's two moons in a single orbit can be disqualified because they're obviously not "planets". They're not even big enough to be spheroidal, which is required by most definitions of a planet.
But the fact remains that our solar system contains at least three example of paired bodies sharing an orbit about their primary, and periodically exchanging the lead position. The mechanics of such orbits have been long understood, and astrophysicists can tell you when such orbits are stable. So while this may be "news" in the sense that it's about such orbits around another star, it's hardly news in the astrophysics sense.
What'll be interesting news is the discovery of three astronomical bodies in a "Scottish reel" orbit, which was proved possible several years ago, but to my knowledge hasn't actually been observed yet. Possible places to find them are in the asteroid belt, in Jupiter's "Trojan" asteroid clumps, and in the Kuiper Belt.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
something SO unnatural, uniform, coated with finely grained sand in general, being produced out of a random collision (the results of which are statistically unlikely to produce something like that in the first place), without any atmospheric or natural conditions acting on its surface ...
the moon is quite unnatural as it is. there is no object flying in solar system that is even remotely similar, even asteroids. there is no need to try to invent far out theories in order to make its statistical absurdity more absurd.
Read radical news here
Is this analysis really just based on 4.5 months of data from May to September 2009? What's taking so long?
The problem with the planet detection methods used by the Kepler team is that it is all calculated based on occultations; the slight dimming of the star's light as a planet passes between that star and the Kepler satellite. This only works if the planet in question is 1) HUGE or 2) very close to the star or 3) the Earth just HAPPENS to be in the plane of the planet's orbit around the star. That's why we're discovering so many enormous planets with orbital periods in the range of only a few days. But the nice thing about the Kepler data seems to be that it's eliminating many of the "it could NEVER have happened that way!" explanations. With upwards of 500 billion stars in the Milky Way galaxy and we've looked only at a few thousand, it looks more and more that ANYTHING is possible when it comes to planetary formation.
Oh, sorry, typed it wrong...
What two consenting planets do doesn't affect other planets' orbits.
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Captain Kirk beams down there, takes his shirt off, and gets the chick. Wait, two planets? Wait a second, we'll have to fly in a second, evil, Captain Kirk from a parallel universe. And how about a Spock with a beard? Does Ryanair fly there? Can we get a discount rate for two? Well, knowing them, they'll charge an extra exorbitant fee for Spock's beard. And the plane won't even land in the parallel universe, but in another universe, "Really close by!"
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Simple! There are many satellites that have left the orbit of earth and now in a solar orbit. Example: the Mars probes (although these might more accurately be Martian orbits). These satellites could easily view the location and send back reports.
Our orbit isn't perfect. So maybe the counter earth would be visible in the sky just beside the sun. But would go behind it and reappear out the other side each time one of the planets passed perihelion. Is our orbit eccentric enough for this?
...may have very well been Mars itself that collided with Earth and got knocked into it's current orbital path. It didn't share an orbit with Earth, but in a crossing orbit before the collision. Mars once had large oceans, which were knocked away in the collision, and the resulting water froze into space ice and was eventually captured by Earth's gravity and is now in our oceans.
Kepler has identified 1200 planet candidates in its first four months of data operations, 19 which had been confirmed as of last week. Graphing the planets by various attributes starts to give a respectable idea of size, year, star-type, density and perhaps other attributes in solar systems. Kepler could find ten times as many planets as these in its 3.5 year nominal, 10-year extended, mission.
These planets are at the stable lagrange points, not in orbit with each other.
Which, by the way, is perfectly fine with regards to the IAU's definition. These planets have cleared their orbit nicely, and are gravitationally bound to each other.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
...is filing a few billion John Doe lawsuits against "Any and all current or potential occupants of said potentially planetary bodies..." for sharing an orbit.
Sharing is bad
How come Slashdot never gets Slashdotted?
Both are to be considered "dwarf planets"
We prefer the term "little planets"... (you insensitive clod!)
There is another hypothesis about a planet "crossing" the earth's orbit. Earth wasn't in it's current orbit, according to this hypothesis, when the collision occured, and Mars was not involved (the refutation of Mars being involved relies on the apparent lack of tectonic activity on Mars), but water knocked into space is involved.
Zecharia Sitchin again. And by all means, ignore his linguistic conclusions (not supported) and his anthropological musings (off-topic). Just stick to the astronomy and cosmology arguements (jaw-dropping). Oh, and he first wrote his stuff in the mid '70s. Before we'd even been to the outer planets. Before we had any evidence of extra-solar planets, -oids, -ismals, etc.
i just found a nickel. i can touch, spend, and more importantly COVER UP YOUR PLANET with it. ha.
There were 12 planets all sharing orbits, orbiting in some stars habitable zone.
But then again there were angels with awesome tits running around too.
Two planets enter, one planet leaves!
Two planets orbiting the same star is arguably only possible with horseshoe orbits. If two objects are of similar size so on cannot say one orbits the other, it is described a a double body rather than primary and satellite.
A Lagrangian moon will likely develop into a horseshoe orbit over time.
don't cut it off www.mgmbill.org
Planet...or space station?
DUNH DUNH DUNH!
Yes, the Earth and the Moon share the same orbit too.
Please mod me 1 or troll. It's where the truth is these days, even on Slashdot. Beware the power of moderators everywh
In theory, matter in a disc of material around a newborn star could coalesce into so-called "co-orbiting" planets, but no one had spotted evidence of this before.
Off course not. Even star turtles like a little privacy.
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
The ads keep getting larger and larger and the article keeps getting smaller.
The derivation of Lagrange's result linked from the NASA page you just linked is probably about as good as any explanation you'll find outside a $100+ textbook, and better than some of those as well.
"I can't imagine how things could get any worse!" (some guy) "That could just be failure of imaginatioÂn on your p
Finally, somebody has discovered a counter Earth!
Okay, they had to look in another solar system so it's not really a counter "Earth," but still. The real question is whether this will inspire John Norman to publish a new installment in his Gor series.
Nine for Mortal Men doomed to die...
Doppelgänger (Journey To The Far Side Of The Sun).
Isn't an orbit determined by the center of the rotation? The Earth is in orbit around the Sun and the moon is in orbit around the Earth.
Why isn't moon capitalized? Because it's not a planet! Now go to your room!
The Moon is capitalized because its a proper noun in this usage. In general usage we call the moon that is orbiting the Earth simply "the Moon". And since there is only one moon orbiting the Earth and it is referred to as the Moon, it is correct to capitalize it.
In the solar system there are many moons but there is only one Moon.
No, not belts. You know. Like, rings, dude. You know that's what Kepler's *really* for, right?
These are my friends, See how they glisten. See this one shine, how he smiles in the light.