Let me see if I can illustrate this. Take the Earth, a planet approximately 8000 miles in diameter. Put that at the scale of one inch. On the same scale, the distance from the Earth to the Sun is 978 feet.
Now, draw a circle with a radius of 978 feet. Your one-inch planet is somewhere in the circumference of that circle.
Okay? Multiply that original distance by about 200 times. Draw THAT circle. Bring a lunch.
Personally, I’m always excited about news like this. But in all fairness I view this as a very succesful case of how to frame and spin to get attention. As mentioned, Pluto lost its planet status, partly because of its anomalous trajectory and partly because if Pluto was included, we’d have to include a whole lot of other ‘trans Neptunian objects’ as they’re now called. So far I have heard little more than that it’s huge and far away and nothing about trajectory.
So let’s face it: if the press release stated that there *might *be a hitherto unknown trans Neptunian object, I doubt we’d be discussing it at all.
Good news, though - the planet you’re looking for is probably a bit bigger than Earth, so you’re looking for a baseball, not a ping-pong ball.
Attention, Astronomers: I don’t care whether you decide it’s the ninth planet or the tenth – but when its existence is confirmed, please, please, you have to name it “Yuggoth”!
And don’t be givin’ me no blank looks! You all know exactly what I’m talking about, ya nerds!
Well, we would, if the release said the TNO might be ten times the size of Earth.
I understand that. I understand that the nearest galaxy from the milky way is 2 million light years way. I know how fast light travels. My point was that there are known planets many light years away outside of the milky way that have obviously never been seen but we know they are there because of their gravitational pull. How can an object the size of Neptune be in our own solar system and never be detected before now.
I meant outside the solar system.
Red October, shtanding by… your mother’sh front door, Trebek!
Right now, the best evidence of Nibiru… uh… Planet X is a clustering of space debris beyond Neptune which has a 0.007% probability of happening by chance. Since scientists don’t draw to inside straights, they came up with a more plausible explanation: Their orbits are being influenced by something big enough to be a planet (ten times the mass of Earth) with an extremely long orbit.
How do you think we see objects which are not themselves glowing? By the light they reflect, the light they block, or by how they affect the behavior of what we can already see.
Jupiter is the second most massive thing in the solar system. The Sun and Jupiter between them have the majority of mass in the entire solar system, in fact. On a clear night, Jupiter is a bright-ish speck of light in the night sky. You can figure out it’s not a star because it moves relative to the stars, but you need multiple nights’ worth of observing just to get that much information. We didn’t even know Jupiter had rings until 1979, and they’re huge. (Not like Saturn’s, but, objectively, they’re an order of magnitude bigger around than the Earth at the smallest point.) You certainly can’t see any of the moons without help.
My point is, Jupiter, in all its mass, and for all that it’s literally a reflective ball of gas orbiting a star, barely registers in our visual field. You have to be told where to find the second-biggest thing in the entire Solar System. Now, make the planet an order of magnitude less massive and put it way the Hell out there, beyond Neptune. It isn’t going to be directly visible to anything less than a massive telescope pointed in precisely the right direction at precisely the right time.
It could occult a star, in theory, but that’s even touchier: Everything would have to align to within tiny fractions of a degree and then you’d probably only get a fractional dimming of the star, which you could only detect if you knew it was coming and got real generous about picking signal out of error bars. It’s hard enough to use that method to see a planet occulting the star it’s orbiting.
So we have a third method: See what effect it has on stuff we can see reliably. That’s what we’ve done, but it isn’t enough to prove the planet exists, because other mechanisms could have the same effect. (It could even just be chance. Unlikely things happen.) That’s why we’ll have to get a big telescope to try to verify the hypothesis.
And don’t even get him started on how far it is to the chemist’s.
All the exoplanets astronomers have identified are ~much~ closer to their suns than the postulated Planet Nine is to ours.
Also, some of the methods used to spot them don’t work for observers who are themselves inside the orbit of the target planet.
I have placed a baseball at least 35, but no more than 200 miles from you. Let me know when you find it.
Dude, far out.
I think it should be called Diana, because Artemis is my favorite goddess, and there’s only Venus.
Isn’t this how Neptune was eventually found - irregularities in Uranus’ orbit explained by another large planet further away?
[QUOTE=Peremensoe]
I have placed a baseball at least 35, but no more than 200 miles from you. Let me know when you find it.
[/QUOTE]
Did you also paint it black and only allow him to look at night? 
Challenge: I hid a baseball and I had it painted black.
Conditions: No vision anymore, you have to use a bat.
Be sure you don’t mistake it for a stone rolling around.
We have never detected any evidence for a planet in another galaxy, and such a feat is insanely beyond our technological capabilities. We have detected evidence for many planets around other stars, but those stars have all been not only within our Galaxy, but within a very small region of our Galaxy.
The Sun all by itself has over 99% of the Solar System’s mass, so your statement is trivially true. What you might have meant to say is that Jupiter is the majority of the Solar System’s non-star mass.
And Jupiter is not hard to notice at all. If you take someone who knows nothing of astronomy out on a clear night when Jupiter is up, they’ll point to it and say “What’s that really bright star?”. Unless Venus is up, too, in which case they’ll first point to it and say “Is that really bright thing a star or an airplane?”, and then after that they’ll point to Jupiter and say “And what about that other really bright star?”.
Given the constraints of where the planet’s orbit must be to shepherd the various trans-neptunian objects the paper talks about is there enough information to go back into old plates/data archives to look for an incredibly slow moving point of light?
If I heard right and remember correctly* Mike Brown in the radio interview I heard said the orbit would be about 10,000 years.
Again, if I heard right and remember correctly, Mike said there’s only a couple of existing telescopes capable of testing the hypothesis.
*I listen to the radio while I work so most times I’m only half-listening.
This is likely true but has not been demonstrated as unequivocal fact. As recently as 1994(Bailey) the Oort cloud was estimated to mass more than Jupiter, though more recent estimates put it much less than that.