New details about planet 2007 OR10, third largest dwarf planet in solar system | Hacker News Reader

New details about planet 2007 OR10, third largest dwarf planet in solar system

gizmodo.com

67 pointscurtis39 comments

Its orbit in relation to other far out planets: https://upload.wikimedia.org/wikipedia/commons/b/bc/2007OR10...

Thanks, that's the context that we need. It seems rather odd that someone could write a whole article without going into where "in Our Solar System" this body orbits.

Obviously it's not going to be in the inner solar system, but it seems odd not to even mention the basic comparisons to e.g. the orbits of Pluto or Eris.

Summary: It is out past Neptune, has a similar kind of orbit to Eris.

Odd but not too rare, unfortunately. I've seen countless articles about the contents of a photograph or piece of art that did not include an image of any type. Puzzling.

> about the contents of a photograph or piece of art

That often happens because of copyrights.

How can that be? That sounds like the most uncontroversial example of fair use.

You start by searching for an image that has been released in the public domain or made available under a permissive license. If you can't find one, you can create your own. In this case, the orbit information itself isn't going to be copywritten, so of course you can scribble one out on your own. It's another thing entirely to just google for an existing image and use it without consent.

Fair use doesn't apply everywhere in the world.

>Fair use is a legal doctrine only in the United States.[0]

In the UK, for example, their fair dealing exception is only for "non-commercial research or study, criticism or review". [1]

[0] https://en.wikipedia.org/wiki/Fair_use

[1] https://en.wikipedia.org/wiki/Fair_dealing_in_United_Kingdom...

The term "fair use" seems to only exist in the United States, but the same concept exists in more places. Such as Sweden, for instance, where it's called "skäligt bruk".

https://sv.wikipedia.org/wiki/Fair_use

I was wondering the same. Can only guess that was not mentioned since location was known since 2007. Only new information is size.

Huh. I wonder how close Eris and this new one could potentially come to Pluto.

Wiki says it's in a resonance with Neptune (Pluto is as well, and Eris might be), so probably "not that close".

Yep, I assumed something like that. In general, if substantial bodies are still around in the solar system after all this time, it is because they have come to an arrangement with their neighbours.

Yes. When it's that far out, it's easy to hide. :-) But still very exciting!

I am baffled by the article's frequent use of the word Kepler. The first mention is correct: "New planets are uncovered all the time, thanks to Kepler. In fact, the mission just unearthed a stash of more than 1,200 new exoplanets, bringing its total haul to over 3,200."

This refers to the Kepler Mission[1] which points to a fixed spot in interstellar space and finds exoplanets. But that mission has NOTHING to do with our solar system. It isn't pointed anywhere near the solar ecliptic and couldn't see a local planet if it was.

So when it says "That lack of reflective light made it hard for Kepler to even spot the planet" it is being ignorantly misleading, and when it says "although Kepler managed to catch brief glimpse in 2014" it is just wrong. "the Konkoly researchers hadn’t thought to pair NASA Kepler data with ESA Herschel data" -- for very good reason, Kepler data would be completely irrelevant. "information about the amount of light the planet was reflecting from Kepler..." again, completely impossible and wrong.

The byline is Ria Misra, clearly a person who should not be allowed to write about astronomy anytime soon.

[1] http://kepler.nasa.gov/

The abstract of the paper[0] clearly says

> We combined optical light curves provided by the Kepler Space Telescope–K2 extended mission and thermal infrared data provided by the Herschel Space Observatory.

Kepler hasn't been staring at the same patch of stars for a while now[1]

[0] http://iopscience.iop.org/article/10.3847/0004-6256/151/5/11... [1] https://en.wikipedia.org/wiki/Kepler_(spacecraft)#Second_Lig...

Thank you. It appears I was wrong.

This was discovered in 2007 and thought to be a dwarf planet even then. The new information here is a more accurate estimate of it's size that moves it from 5th largest to 3rd largest dwarf planet. The title is click bait.

Ok, we changed the title to a representative phrase from the article.

It's original discoverer, Mike Brown, wrote a few blog posts about this object back in 2011 that are worth reading: http://www.mikebrownsplanets.com/2011/08/redemption-of-snow-...

Here's the actual paper: http://arxiv.org/abs/1603.03090

Sigh, not Planet X: http://www.sciencemag.org/news/2016/01/feature-astronomers-s...

I'm hoping for planet McPlanetface myself...

Not dwarfy mcdwarfface?

Perhaps one of the more interesting things in this article was the depiction of Haumea [0]. I had no clue planets could have an elliptical shape. Pretty cool. Apparently it hasn't been directly observed, but it's shape has been calculated from its "light curve".

[0](https://en.wikipedia.org/wiki/Haumea)

>> I had no clue planets could have an elliptical shape.

They can't, as one of the defining characteristics of a planet is having enough mass to be rounded under it's own gravity. Dwarf planets have no such restriction.

Earth is elliptical - an oblate spheroid - so I would say they can.

Yes, the Earth is an oblate spheroid rounded by its own gravity. Despite your tone, you seem to be agreeing.

Almost, if they spin they will bulge in the center.

The reality is we still don't have good definitions for these objects.

> They can't, as one of the defining characteristics of a planet is having enough mass to be rounded under it's own gravity.

The problem here is that "rounded" simply means "roughly spheroid". It's an imprecise term with no rules governing how far from a sphere the objects can deviate and still be considered planets or dwarf planets.

> Dwarf planets have no such restriction.

It is that restriction that separates dwarf planets from large asteroids.

The distinction between planet and dwarf planet has to do with whether or not the object has cleared its orbit of other debris.

That's incorrect. The dwarf planet designation only removes the "must have cleared its orbit" restriction that planets have. They must still be in hydrostatic equilibrium.

Non-spherical objects can still be in hydrostatic equilibrium due to centrifugal forces being anisotropic.

https://en.wikipedia.org/wiki/Dwarf_planet#History_of_the_co...

The massive distances between celestial objects is somewhat beyond human comprehension. The scale of these objects and their orbits is so very different from the scales we encounter on a daily basis. The fact that these bodies can still be discovered proves we know so little about our own cosmic backyard, let alone the intricacies of spacetime.

Although I agree with you that it's in some ways amazing that we can, e.g. spot planets in solar systems hundreds of light-years away and still have discoveries like this one in our own 'backyard', I'd say that the intricacies of spacetime is a rather different issue which is not correlated with our lack of understanding of our own cosmic backyard, except for the fact that both are 'astrophysical' phenomena (spacetime is more GR, but bear with me).

What I mean is that the intricacies of spacetime is something that can be mathematically formulated, tested, and 'known' in a whole different way than how many objects reside in our solar system. It's kind of analogous to saying that not knowing how many species there are on earth means we don't understand how natural selection works.

"A dwarf planet", not "An". Also, too many commas and no need to capitalize every word.

Grammar, FTW.

Re: the commas, see the Free Modifier example from https://en.wikipedia.org/wiki/Comma#Parenthetical_phrases

The commas are not ideal, but neither are they ungrammatical.

Capitalising all words in a headline is an acceptable grammatical style - you'll find it in US newspapers, for example. It does look a bit weird in some cases, however.

That's an pretty surprising finding.

If the naming gets crowdsourced we all know how that ends. Ladies and Gentlemen, I would like to present Rocky McPlanetFace.

Planetey McPlanetFace you pleb. ;)

Oh please. Thingy McThingFace was so 2015:

http://crooksandliars.com/2016/05/zimmerman-gun-sale-hijacke...

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