Hey LORI!

[The Mad Monk]

The suggested planet X has a near circular orbit of 20,000 years, IIRC.

What would it look like if it were a highly elliptical orbit of 20,000 years, that passed within, oh, say, 1 AU of Earth's orbit?

Bonus question: how much havoc would this wreak, and what is the likelihood of ejection by Jupiter?

Bonus Bonus question: how stupid is Nibiru, anyway? I think it's pretty stupid, but I'm looking for confirmation.

[Lorizael]

Well, Kepler's third law applies. Circular or elliptical, the semi-major axis of a planet with a period of 20,000 years is 20,000^(2/3) ~ 700 AU. (I'm rounding a lot.) But if the planet has a perihelion of ~1 AU, then its eccentricity is 0.999 and its aphelion is ~1400 AU.

Ejection during passes through the solar system start to look increasingly likely. If the planet is perturbed by another planet and gains energy in the process, this may bump its eccentricity to >=1, which means (more or less) that it's not coming back. I couldn't give you exact probabilities because that would involve a lot of math and/or simulation. As far as how much damage it would wreak, maybe not much. Its extreme orbital eccentricity means that it's not spending a lot of time in the inner solar system (Kepler's second law: equal areas swept out in equal times).

Nibiru is pretty stupid, although my understanding is that there are many different versions of what Nibiru means, so quantifying the stupidity precisely is hard.

[Egbert]

I hadn't heard of this conspiracy theory. So I looked it up and I learnt that this Niburu planet will destroy us all in AD 2012.

https://sservi.nasa.gov/articles/scientists-reject-impending-nibiru-earth-collision/

[Sava]

can you calculate the circumference of uranus

[Ben Kenobi]

I'm not so sure about that, Lori. 1400 AU is a long way out. Eris is the only thing we've found so far at about 100 AU. WISE says that they could find anything out to the size of Neptune out to about 700 AU. I'd guess then about Saturnian mass out to 1400 would be the constraint. That's still a pretty large nemesis.

[Uncle Sparky]

can you calculate the circumference of uranus

Today is taco Tuesday, so no...

[Dinner]

Hmm, two for one TJ style street tacos today as my favorite local taco joint. They even have been stocking some craft beers from down in TJ though I have been abstaining for a while now. I have been surprised at the quality and number of craft breweries down there lately. Apparently, a bunch of Mexicans have been working in 120 or so craft breweries here in San Diego and several of them have returned home to open their own breweries fown south. It is always nice to have additional options and styles.

[pchang]

What is Nibiru's mass supposed to be? I doubt it would do much to Earth directly, but it might bump a few asteroids/comets around. If we were really unlucky, one of them might hit the Earth.

[Sava]

lori you should start a business

the math you do for your classes is tougher than anything you'll ever do

[Lorizael]

I'm not so sure about that, Lori. 1400 AU is a long way out. Eris is the only thing we've found so far at about 100 AU. WISE says that they could find anything out to the size of Neptune out to about 700 AU. I'd guess then about Saturnian mass out to 1400 would be the constraint. That's still a pretty large nemesis.

You have misread my post.

[Lorizael]

lori you should start a business

the math you do for your classes is tougher than anything you'll ever do

Possibly, but the math I've done in this thread is arithmetic...

[pchang]

If Lori could just solve the 3 body problem he'd really be on to something.

[The Mad Monk]

Well, Kepler's third law applies. Circular or elliptical, the semi-major axis of a planet with a period of 20,000 years is 20,000^(2/3) ~ 700 AU. (I'm rounding a lot.) But if the planet has a perihelion of ~1 AU, then its eccentricity is 0.999 and its aphelion is ~1400 AU.

Ejection during passes through the solar system start to look increasingly likely. If the planet is perturbed by another planet and gains energy in the process, this may bump its eccentricity to >=1, which means (more or less) that it's not coming back. I couldn't give you exact probabilities because that would involve a lot of math and/or simulation. As far as how much damage it would wreak, maybe not much. Its extreme orbital eccentricity means that it's not spending a lot of time in the inner solar system (Kepler's second law: equal areas swept out in equal times).

Nibiru is pretty stupid, although my understanding is that there are many different versions of what Nibiru means, so quantifying the stupidity precisely is hard.

That's what I thought. Thanks.

[Lorizael]

If Lori could just solve the 3 body problem he'd really be on to something.

Lori needs to work on the 2-body problem first...

[Ben Kenobi]

How so? Weren't you discussing the constraints around Niberu? Sorry if I misunderstood. I realize the idea that it's a red dwarf is nonsensical, but a gas giant as far as I know would still be possible.