New evidence found for Planet 9 | Hacker News Reader

New evidence found for Planet 9

phys.org

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We used to have a perfectly adequate Planet 9, until it was declared unworthy of planethood.

Those devils!

Remember Pluto!

Planet 9 should be Neptune.

Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Orcus, Haumea, Makemake, Eris, etc.

If you want Pluto back you have to take Charon as well! Don't discriminate, accept all the astronomical bodies in hydrostatic equilibrium orbiting the Sun!

What about Luna?

The plutonic discourse aside, Earth-Moon is often described as a double-planet system.

The barycenter of the Earth-Luna system is (currently) entirely within the Earth. So Luna is a moon. Once it's outside the radius of Earth, then it'd be a double-planet system (or a double dwarf-planet system if that nomenclature lasts).

Wait until you open the arxiv paper and find that one of the authors is Michael E Brown, the self-proclaimed “guy who killed Pluto”

Suits him well. Now he's looking for a replacement for the planet he killed.

Poor Ceres.

If you live in Arizona, you still do!

Why will this stupid meme not die?

A ton of us grew up reciting

    Mercury
    Venus
    Earth
    Mars
    Jupiter
    Saturn
    Uranus
    Neptune
    PLUTO

But, the meme doesn’t die because the deplanetization of Pluto was a weird occurrence that doesn’t usually happen. The biggest association I have with Pluto is that it used to be a planet, so why wouldn’t I joke about that every time I see it mentioned?

It's boring? It's like when an old person makes a joke they make every time you see them. It's utterly boring and devoid of joy.

You do you but indifference turns to resentment.

It's boring? It's like when an old person makes a joke they make every time you see them. It's utterly boring and devoid of joy.

Whenever I see this situation, there's the one person who is joyous, and the other one who is resentful. It makes more sense that the emotional energy is much more the function of the negativity of the resentful party, than it is any fault of the joyous one.

Don't forget that Ceres, Pallas, Juno, and Vesta were once considered planets as well. Generations of schoolchildren memorized their names right alongside the others.

I’m not THAT old

I didn't say that you were. I said that you should put yourself in the shoes of those older generations of students who memorized the names of the 11 planets. Or the 13, or 17, or dozens or however many had been discovered the year that their textbook was printed. Eventually they just gave up and started calling them all “the Asteroid Belt”.

If we had repeated history more closely, students would have memorized the names of the first few Kuiper Belt and Oort Cloud objects to be discovered. Repeat after me: Pluto, Albion (aka 1994 QB₁), 1993 SB, 1993 SC, 1994 GV₉, Arawn (aka 1994 JR₁), 1994 TB…

Or if you prefer to order them by size: Pluto, Eris, Haumea, Makemake, Gonggong, Quaoar, Ceres, Orcus, Sedna, Salacia, 2002 MS₄, 2002 AW₁₉₇, Varda, etc, etc.

Sorry, was a joke, I didn't realize there were people taking this thread so seriously!

Mary visits every monday, just stays until noon period.

Neptune is still fully imbued of planet-hood, regardless if you prefer to call Ceres a planet or dwarf-planet.

Has Ceres ever been classified as a planet ? Inquiring minds want to know.

Yes. In the early decades of the 1800s, the asteroids Ceres, Pallas, Juno, and Vesta were commonly included in the list of planets. The number of known asteroids exploded in the 1840s and 50s with the 100th being discovered in 1868. I'm not actually sure when schoolchildren stopped memorizing their names.

It's still considered a dwarf planet fwiw

Check the size of the Planet 9 on the Wikipedia.

Check the size of the Earth's Moon.

...

A small team of planetary scientists from the California Institute of Technology, Université Côte d'Azur and Southwest Research Institute reports possible new evidence of Planet 9. They have published their paper on the arXiv preprint server, and it has been accepted for publication in The Astrophysical Journal Letters.

"The solar system's distant reaches exhibit a wealth of anomalous dynamical structure, hinting at the presence of a yet-undetected, massive trans-Neptunian body - Planet 9. Previous analyses have shown how orbital evolution induced by this object can explain the origins of a broad assortment of exotic orbits, ranging from those characterized by high perihelia to those with extreme inclinations. In this work, we shift the focus toward a more conventional class of TNOs, and consider the observed census of long-period, nearly planar, Neptune-crossing objects as a hitherto-unexplored probe of the Planet 9 hypothesis. To this end, we carry out comprehensive N−body simulations that self-consistently model gravitational perturbations from all giant planets, the Galactic tide, as well as passing stars, stemming from initial conditions that account for the primordial giant planet migration and sun's early evolution within a star cluster. Accounting for observational biases, our results reveal that the orbital architecture of this group of objects aligns closely with the predictions of the P9-inclusive model. In stark contrast, the P9-free scenario is statistically rejected at a ∼5σ confidence-level. Accordingly, this work introduces a new line of evidence supporting the existence of Planet 9 and further delineates a series of observational predictions poised for near-term resolution."

https://arxiv.org/abs/2404.11594

How long after LSST comes online untill we are sure to discover it or rule it out?

Forgive my ignorance. If it's so relatively close, why wouldn't it be observed optically hiding some known objects? Mostly stars.

If it's so relatively close

Relatively close is still frightfully far away.

why wouldn't it be observed optically hiding some known objects? Mostly stars.

It's angle subtended is still awfully teeny.

One of the options is that it's a primordial black hole, which leads to my favourite "actual size" caption on a diagram, page 5:

https://arxiv.org/pdf/1909.11090

I don't know why but that's... disconcerting. So small, but so powerful...

Honestly finding such an object so close by would be incredible.

Nothing would be more exciting for theoretical physicists than a small black hole in the solar system. It would allow “immediate” access to direct experimental evidence of quantum gravitational phenomena that would otherwise require a round trip journey measured in tens of millennia.

Think about the funding this would unlock: long-duration deep space missions, particle accelerators in space, etc…

It would be a new renaissance for science.

This is getting silly. JWST can image galaxies but can't find Planet 9?

Galaxies have the advantage of emitting their own light. Planets reflect only a tiny fraction of their host star’s light, and the inverse square law hits twice.

> theorized

Sorry, how is this evidence?

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