Author Topic: Dwarf planet discovery hints at a hidden Super Earth in solar system  (Read 90845 times)

Offline Star One

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Interview with Mike Brown on his hunt for planet nine.

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Still, not everyone is confident that Planet 9 will be found any time soon—or at all. A new study from a team of scientists at Queen’s University in Belfast asserts that the discovery of a minor planet called 2013 SY99—which is, at its closest, 50 AU—might dash our hopes of ever discovering the world. After running computer models of the solar system, the researchers concluded that if Planet 9 did exist, it likely would have altered SY99's orbit so much we would not be able to view it.

“Computer models do show that a Planet Nine would be an unfriendly neighbor to tiny worlds like SY99: its gravitational influence would starkly change its orbit – throwing it from the solar system entirely, or poking it into an orbit so highly inclined and distant that we wouldn’t be able to see it,” Michele Bannister, an author on the study, wrote in The Conversation. “SY99 would have to be one of an utterly vast throng of small worlds, continuously being sucked in and cast out by the planet.”

Bannister told Gizmodo that while her team’s findings don’t entirely disprove the idea of Planet 9, it calls the hypothetical world’s legitimacy into question.

“The planet 9 idea is a fun idea, it’s exciting, but it’s taking a bit of the oxygen at the moment,” she told Gizmodo. “We have this interesting problem…and the very shiny solution at the moment is called planet 9.”

Brown, on the other hand, read Bannister’s paper and said he and Batgyin had predicted that astronomers would discover objects just like SY99. He said that finding these objects actually reinforces the idea that Planet 9 is out there.

“The reason that we initially thought Planet 9 existed—there are a lot more reasons now—but the initial reasons were that the most distant Kuiper Belt objects were on these very eccentric orbits that are all pointing off in the same direction,” he told Gizmodo. “One of the things we said when we first announced this a year ago was that, ‘We predict that as you continue to find more and more distant Kuiper Belt objects, they too will be pushed off in this one direction. So we’ve been waiting for all these discoveries to come in—this one is exactly where it’s predicted.”

http://gizmodo.com/when-the-hell-will-we-find-planet-nine-1794681137

Offline Star One

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Offline KelvinZero

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Scientists need your help to find the mysterious planet they suspect is lurking in our solar system

http://mashable.com/2017/02/16/planet-nine-database-hunt
Have they considered walking backwards slowly? That always works in horror movies  :)

Offline Star One

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New paper incoming from Mike Brown.

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Mike Brown @plutokiller

Replying to @DesslerAlex
Why the clustering of distant eccentric KBOs is not an observational bias (I'll show you Thursday!)

https://mobile.twitter.com/plutokiller/status/863907009258692608

Offline Star One

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Hubble spots moon around third largest dwarf planet

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The combined power of three space observatories, including NASA’s Hubble Space Telescope, has helped astronomers uncover a moon orbiting the third largest dwarf planet, catalogued as 2007 OR10. The pair resides in the frigid outskirts of our solar system called the Kuiper Belt, a realm of icy debris left over from our solar system’s formation 4.6 billion years ago.

https://astronomynow.com/2017/05/18/hubble-spots-moon-around-third-largest-dwarf-planet/

Offline Star One

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Mike Brown @plutokiller

tomorrow's paper will answer the age old question: does observational bias explain the clustering of distant KBOs? (spoiler: no)

https://mobile.twitter.com/plutokiller/status/874685485930602496

Offline CuddlyRocket

The promised paper:

Observational bias and the clustering of distant eccentric Kuiper belt objects (arXiv pdf)

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(Abstract)
The hypothesis that a massive Planet Nine exists in the outer solar system on a distant eccentric orbit was inspired by observations showing that the objects with the most distant eccentric orbits in the Kuiper belt have orbits which are physically aligned, that is, they are clustered in longitude of perihelion and have similar orbital planes. Questions have remained, however, about the effects of observational bias on these observations, particularly on the longitudes of perihelion. Specifically, distant eccentric Kuiper belt objects tend to be faint and only observable near their perihelia, suggesting that the longitudes of perihelion of the known distant objects could be strongly biased by the limited number of locations in the sky where deep surveys have been carried out. We have developed a method to rigorously estimate the longitude of perihelion bias for Kuiper belt observations. We find that the probability that the 10 known Kuiper belt objects with semimajor axis beyond 230 AU are drawn from a population with uniform longitude of perihelion is 1.2%. Combined with the observation that the orbital poles of these object are also clustered, the overall probability of detecting these two independent clusterings in a randomly distributed sample is 0.025%. While observational bias is clearly present in these observations, it is unlikely to explain the observed alignment of the distant eccentric Kuiper belt objects.

Offline Star One

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So the experts amongst you what do you think of his paper as it seems to attempt to address one of the major criticisms of his hypothesis?

Offline Bynaus

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And the "complement", the OSSOS team identifying strong biases towards detection of objects with aligned orbits (within that survey).

https://arxiv.org/abs/1706.05348

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OSSOS VI. Striking Biases in the detection of large semimajor axis Trans-Neptunian Objects

The accumulating, but small, set of large semi-major axis trans-Neptunian objects (TNOs) shows an apparent clustering in the orientations of their orbits. This clustering must either be representative of the intrinsic distribution of these TNOs, or else arise as a result of observation biases and/or statistically expected variations for such a small set of detected objects. The clustered TNOs were detected across different and independent surveys, which has led to claims that the detections are therefore free of observational bias. This apparent clustering has led to the so-called "Planet 9" hypothesis that a super-Earth currently resides in the distant solar system and causes this clustering. The Outer Solar System Origins Survey (OSSOS) is a large program that ran on the Canada-France-Hawaii Telescope from 2013--2017, discovering more than 800 new TNOs. One of the primary design goals of OSSOS was the careful determination of observational biases that would manifest within the detected sample. We demonstrate the striking and non-intuitive biases that exist for the detection of TNOs with large semi-major axes. The eight large semi-major axis OSSOS detections are an independent dataset, of comparable size to the conglomerate samples used in previous studies. We conclude that the orbital distribution of the OSSOS sample is consistent with being detected from a uniform underlying angular distribution.

Offline CuddlyRocket

Mike Brown has been tweeting on the OSSOS paper:

Mike Brown‏ @plutokiller  12h12 hours ago
Planet Nine fans! OK, so I'm on vacation but I haven't quite left for the airport yet, so a quick take on the new OSSOS paper.

Mike Brown‏ @plutokiller
they demonstrate nicely that their survey is strongly biased. I would 100% agree; they look in limited places in the sky, that makes biases.

Mike Brown‏ @plutokiller  12h12 hours ago
the take home message is that, sadly, OSSOS is not so good for understanding perihelion clustering. which makes sense.

Mike Brown‏ @plutokiller  12h12 hours ago
they then make the leap to say that therefore it is probably true that NO survey is good for understanding perihelion clustering.

Mike Brown‏ @plutokiller  12h12 hours ago
Luckily, just last week I posted that paper showing, in fact, that the combination of previous surveys does a great job w/perihelion cluster

Mike Brown‏ @plutokiller  12h12 hours ago
so I'd say the OSSOS paper is relatively neutral for Planet Nine. Which is too bad. A different survey strategy could have been definite.

Mike Brown‏ @plutokiller  12h12 hours ago
But no one was thinking about P9 back when their survey was designed.

Offline Star One

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Planet ten or nine depending on which way you count all these proposed planets we seem to have missed. Though whether this is another planet gets caught up in how we define planets now.

The curious case of the warped Kuiper Belt

https://astronomynow.com/2017/06/22/the-curious-case-of-the-warped-kuiper-belt/

Here's the original press release.

https://uanews.arizona.edu/story/ua-scientists-and-curious-case-warped-kuiper-belt

I suppose there's no chance New Horizons might spot this?
« Last Edit: 06/23/2017 07:19 AM by Star One »

Offline CuddlyRocket

Though whether this is another planet gets caught up in how we define planets now.

I will cross-post this to the Pluto-Planet debate discussion thread to deal with that aspect!

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I suppose there's no chance New Horizons got spot this?

Very slim - space is big and Mars-sized objects are small!

Offline kevin-rf

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I suppose there's no chance New Horizons might spot this?

More fun would be it having enough hydrazine for a flyby.
« Last Edit: 06/24/2017 03:58 PM by kevin-rf »
Sharknado 5: Global Swarming
Make America Bait Again!

Offline Star One

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Is there anyway from the way objects in the Kuiper belt are being twisted of trying to estimate where this body might be lurking?
« Last Edit: 06/24/2017 04:01 PM by Star One »

Offline ugordan

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Is there anyway from the way objects in the Kuiper belt are being twisted of trying to estimate where this body might be lurking?

Mike Brown already addressed that at one point, it's not possible because you need to have a long tracking arc to pick up perturbations to Keplerian orbits. Kuiper belt objects, by the very fact they're so far out, move in their orbits glacially slowly.

Interestingly enough, they did try using Cassini's precision measurements of Saturn's location over the last decade or so to see if any large object noticeably perturbed it. Inconclusive results IIRC.
« Last Edit: 06/24/2017 04:06 PM by ugordan »

Offline Star One

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Is there anyway from the way objects in the Kuiper belt are being twisted of trying to estimate where this body might be lurking?

Mike Brown already addressed that at one point, it's not possible because you need to have a long tracking arc to pick up perturbations to Keplerian orbits. Kuiper belt objects, by the very fact they're so far out, move in their orbits glacially slowly.

Interestingly enough, they did try using Cassini's precision measurements of Saturn's location over the last decade or so to see if any large object noticeably perturbed it. Inconclusive results IIRC.

Wasn't that in reference to planet 9 rather than this object?

Offline ugordan

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Doesn't change the argument any.

Offline gospacex

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Interestingly enough, they did try using Cassini's precision measurements of Saturn's location over the last decade or so to see if any large object noticeably perturbed it. Inconclusive results IIRC.

Actually, analysis of Cassini data does have a hint at a perturbation is a specific direction. It's just quite close to noise floor, so they can't with confidence say that "something is definitely there". Also, the precision of that direction is quite low, so it's not really helping astronomers to limit the search area.

Offline Star One

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Interestingly enough, they did try using Cassini's precision measurements of Saturn's location over the last decade or so to see if any large object noticeably perturbed it. Inconclusive results IIRC.

Actually, analysis of Cassini data does have a hint at a perturbation is a specific direction. It's just quite close to noise floor, so they can't with confidence say that "something is definitely there". Also, the precision of that direction is quite low, so it's not really helping astronomers to limit the search area.

Did it indicate this body might be the galactic plane?

Offline gospacex

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Galactic plane pulls all bodies in Solar System equally, Saturn and Earth including. Timing of Cassini signals wouldn't detect that.

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