Evidence is Mounting That a World the Size of Neptune Could be Orbiting a Giant Planet Far, Far Away (nationalgeographic.com) 66
About 8,000 light-years away, a giant planet circles an aging star, marching once around its sun in a single Earth-year. But that planet, called Kepler 1625b, might not be traveling completely alone. From a report: Scientists now suspect the planet's skies are filled by an orbiting mega-moon, a stunningly large world the size of Neptune that may be the first moon spotted outside our solar system. Early hints of its existence surfaced in July 2017, when scientists tentatively announced that they'd found some evidence of an orbital companion for Kepler 1625b. But it wasn't until the Hubble Space Telescope aimed its eye at the faraway star a year ago that scientists were able to gather enough data to build the case for the so-called exomoon's presence. Now, the two scientists behind the discovery are hoping for independent confirmation of their finding to really shore up the extraordinary claim.
"I'm confident that we've done a thorough job vetting this thing, but I also anticipate there will be things other folks come up with that we might not have considered," says Columbia University's Alex Teachey, who reports the purported alien moon this week in the journal Science Advances. "Whether those other ideas are fatal to the moon hypothesis or not, that remains to be seen." For now, MIT's Sara Seager says she's reserving judgment. "Exomoons are one of the key items remaining on exoplanet researchers' wish list," Seager says. "It's exciting to see the hunt for the first exomoon continue ... and with what would be a shockingly large moon, about the size and mass of Neptune."
"I'm confident that we've done a thorough job vetting this thing, but I also anticipate there will be things other folks come up with that we might not have considered," says Columbia University's Alex Teachey, who reports the purported alien moon this week in the journal Science Advances. "Whether those other ideas are fatal to the moon hypothesis or not, that remains to be seen." For now, MIT's Sara Seager says she's reserving judgment. "Exomoons are one of the key items remaining on exoplanet researchers' wish list," Seager says. "It's exciting to see the hunt for the first exomoon continue ... and with what would be a shockingly large moon, about the size and mass of Neptune."
Getting there (Score:1)
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There is no "arrive", only "flyby"
No spacecraft we have launched so far has any way of "coming to rest" (relatively speaking) after getting up to that sort of speed.
Other than direct impact, of course.
Indeed. Those dumbasses at NASA and other space agencies are much too stupid to think of this. They would never, ever think to add anything like long duration retro rockets. Nope, you're the very first to consider that. How clever you must be!
not with that additude! (Score:2)
Where are we going?
Planet Ten!
When?
Real soon!
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You insensitive clod! you beat me to it :)
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Right, everyone "knew" this to be the case, but the point is that we can now (sorta) detect them, which opens the door to other interesting kinds of observations and collection of science data.
It isn't about being surprised by exomoons, it's about being able to detect exomoons.
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And like there's an entire universe in your fingers. Right there man. It's galaxies within galaxies. That where they come from. The blue people and why they're so short. Where's the pizza?
That's no Moon (Score:1)
That's no Moon....
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That's no Moon....
Is it? It certainly confronts whoever is supposed to decide how to define the term 'moon' with some very interesting questions. As far as I could discover in a 60 second web search, a moon is simply defined to be a celestial body that makes an orbit around a planet including dwarf planets, and minor planets. There are no size restrictions. It does undeniably seem a bit odd that this thing, which is something like 4 times bigger than earth, qualifies as a mere 'moon'.
Re:That's no Moon (Score:5, Insightful)
Oh man.
What is our youth coming to?
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What is our youth coming to?
Porn, mostly.
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Oh man.
What is our youth coming to?
Maybe they grew up a bit and started watching Star Trek instead?
*Runs for cover*
That's no moon.... (Score:3)
It's a space station.
Moon, no moon, that's not the important thing here (Score:5, Interesting)
The important thing here is THIS IS HOW SCIENCE IS SUPPOSED TO WORK. "Hey, we think we found this thing. We're pretty sure, but we're not going to say anything definite until it's independently confirmed by other people. Here's the data we used, here's how we got it, and here's how we used it, now please someone else check this out and see if we're right."
Planet X (Score:1)
Because PLUTO is still planet 9 and a giant mystery planet must be name “PLANET X.”
And because X means 10.
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Planet 9? Planet 9? Planet 9?
(Backward masked...)
Turn me on, Uranus. Turn me on, Uranus. Turn me on, Uranus.
(Sorry, best I can come up with while baked.)
No, Planet XIII or higher (Score:2)
Because PLUTO is still planet 9 and a giant mystery planet must be name “PLANET X.”
The problem with that is that if Pluto is classed as a planet then we already have planets 10 [wikipedia.org], 11 [wikipedia.org] and 12 [wikipedia.org] and possibly more.
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Re: No, Planet XIII or higher (Score:2)
Why?
Are you assuming some specific definition of planet? Because it's not going to be one planetary scientists recognize. If it were, you'd not be so sure.
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They're structurally different, have different composition and formed differently at a different time.
So every intrinsic property differs.
I don't need an arbitrary definition, just one by scientists.
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They're structurally different, have different composition and formed differently at a different time.
So are the current planets so if you are going to suddenly start differentiating based on this you are clearly going to be using arbitrary constraints that are purely designed to let the current planets pass plus Pluto and reject anything else. This sorts of constraints are going to then be tied specifically to our solar system and will not work for any other. You are effectively classifying something by how you feel about it and then coming up with criteria to give you that result: that's nothing to do w
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No, all existing planets are stratified, have a single solid or liquid core, formed at high energy and have heavy elements. No asteroid or comet can claim all of these. Indeed, no asteroid or comet can claim any of them.
I cannot believe I have to post something so mindboggingly obvious.
I cannot believe that you would post something so mindboggingly wrong.
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And we shall name this planet (Score:1)
Once in a Blue Moon (Score:2)
If it looks anything like Neptune, then it's a blue moon.
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I guess it's a smurf planet.
Inevitable (Score:2)
Probably a capture. But it's the density of the host planet - ten times Jupiter's - that is really interesting and being largely ignored.
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Probably a capture. But it's the density of the host planet - ten times Jupiter's - that is really interesting and being largely ignored.
Larger gas giants have greater densities so appear smaller than their mass would suggest.
Capture requires a significant third body [stackexchange.com].
Gassy (Score:2)
If it is a gassy planet as they say, it should be called Taco Bell.
Moon? (Score:2)
I suppose this is where definitions start getting a bit muddy due to scale.
However are they certain there aren't binary planets? I mean if you can have binary stars that orbit each other around a central pivot, why not planets as well? Again didn't rtfa so I don't know how massive the planet is to it's "moon", which I assume is how this might be defined at least for orbitary (word?) purposes...
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I suppose this is where definitions start getting a bit muddy due to scale.
However are they certain there aren't binary planets? I mean if you can have binary stars that orbit each other around a central pivot, why not planets as well? Again didn't rtfa so I don't know how massive the planet is to it's "moon", which I assume is how this might be defined at least for orbitary (word?) purposes...
There is no agreed upon definition for binary planets. Under some definitions [wikipedia.org], the Earth-Moon system counts because the Sun exerts a greater force on the Moon than the Earth does. If the barycenter definition is used, then the Earth-Moon system will become a double planet in a few hundred million years.