Planet 9 from Outer Space

[Winston]

Planet Nine

https://en.wikipedia.org/wiki/Planet_Nine

"Planet Nine is a hypothetical large planet in the far outer Solar System, the gravitational effects of which would explain the improbable orbital configuration of a group of trans-Neptunian objects (TNOs) that orbit mostly beyond the Kuiper belt.

The predicted planet would be a super-Earth, with an estimated mass of 10 Earths (approximately 5,000 times the mass of Pluto), a diameter two to four times that of Earth, and a highly elliptical orbit with an orbital period of approximately 15,000 years."

Theft behind Planet 9 in our solar system

https://phys.org/news/2016-05-theft-planet-solar.html

Through a computer-simulated study, astronomers at Lund University in Sweden show that it is highly likely that the so-called Planet 9 is an exoplanet. This would make it the first exoplanet to be discovered inside our own solar system. The theory is that our sun, in its youth some 4.5 billion years ago, stole Planet 9 from its original star.

An extrasolar planet, or exoplanet, is by definition a planet located outside our solar system. Now it appears that this definition is no longer viable. According to astronomers in Lund, there is a lot to indicate that Planet 9 was captured by the young sun and has been a part of our solar system completely undetected ever since.

"It is almost ironic that while astronomers often find exoplanets hundreds of light years away in other solar systems, there's probably one hiding in our own backyard", says Alexander Mustill, astronomer at Lund University.

Planet Nine is still hypothetical. However:

Gravitational Perturbations and the Prediction of New Planets

In 1846, the planet Neptune was discovered after its existence was predicted because of discrepancies between calculations and data for the planet Uranus. Astronomers found the new planet almost exactly at the position predicted by the calculations of Leverrier (Adams had also calculated the position independently).

Later, similar calculations on supposed perturbations of the orbits of Uranus and Neptune suggested the presence of yet another planet beyond the orbit of Neptune. Eventually, in 1930, a new planet Pluto was discovered, but we now know that the calculations in this case were also in error because of an incorrect assumption about the mass of the new planet. It is now believed that the supposed deviations in the orbits of Neptune and Uranus were errors in measurement because the actual properties of Pluto would not have accounted for the supposed perturbations. Thus, the discovery of Pluto was a kind of accident.

Researcher links mass extinctions to 'Planet X'
March 30, 2016

https://phys.org/news/2016-03-links-mass-extinctions-planet.html

Planet X being Planet Nine. One of the previous theories was that the periodic comet storms that must have taken place to explain the periodic mass extinction impacts, "storms" since the odds of Earth impacts from small numbers are extremely low, were caused by the orbit of the solar system in the galaxy taking it through dust arms which disturbed the Oort Cloud. It looks like the actual cause might be much closer.

 

[Winston]

A New World’s Extraordinary Orbit Points to Planet Nine
15 May 2018

https://www.quantamagazine.org/a-new-worlds-extraordinary-orbit-points-to-planet-nine-20180515/

In early 2016, two planetary scientists declared that a ghost planet is hiding in the depths of the solar system, well beyond the orbit of Pluto. Their claim, which they made based on the curious orbits of distant icy worlds, quickly sparked a race to find this so-called Planet Nine — a planet that is estimated to be about 10 times the mass of Earth. “It has a real magnetism to it,” said Gregory Laughlin, an astronomer at Yale University. “I mean, finding a 10-Earth-mass planet in our own solar system would be a discovery of unrivaled scientific magnitude.”

Now, astronomers are reporting that they have spotted another distant world — perhaps as large as a dwarf planet — whose orbit is so odd that it is likely to have been shepherded by Planet Nine. The object confirms a specific prediction made by Konstantin Batygin and Michael Brown, the astronomers at the California Institute of Technology who first argued for Planet Nine’s existence. “It’s not proof that Planet Nine exists,” said David Gerdes, an astronomer at the University of Michigan and a co-author on the new paper. “But I would say the presence of an object like this in our solar system bolsters the case for Planet Nine.”

Planet Nine, Show Thyself
Astronomers have found tantalizing new evidence that strengthens the case for a ninth planet beyond Neptune—but some still doubt its existence

https://www.theatlantic.com/science/archive/2018/05/planet-nine-show-thyself/560885/

 

[Winston]

The Growing Case for an Elusive Ninth Planet
Astronomers have found another quirky object that suggests a giant body lurks at the fringes of the solar system.
OCT 2, 2018

https://www.theatlantic.com/science/archive/2018/10/search-planet-nine-solar-system/571831/

The object in question is 2015 TG387, and it sits right in the middle of the mysterious, strange-orbited cluster astronomers have observed in the solar system. When the celestial body was first discovered in 2015, it was about two and a half times farther away from the sun than Pluto is right now. It took astronomers three more years and many more follow-up observations with powerful instruments like the Hubble Space Telescope to track the object and calculate its dramatic orbit:

2015 TG387 takes a whopping 40,000 years to circle the sun. It never actually comes close enough to the solar system’s giant planets—Jupiter, Saturn, Uranus, and Neptune—to feel their gravitational pull. This makes 2015 TG387, as well as other far-flung objects, such as 2012 VP113 and Sedna (also pictured), great candidates for studying the outer solar system.
“It never interacts with anything that we know of in the solar system,” says Scott Sheppard, an astronomer at the Carnegie Institution for Science and a co-discoverer of 2015 TG387. “Somehow, it had to get on this elongated orbit in the past, and that’s the big question: What did it interact with to get [there]?”

To figure that out, Sheppard and his colleagues ran computer simulations of a space environment that included a hypothetical ninth planet. They used calculations proposed by Michael Brown and Konstantin Batygin, a pair of California Institute of Technology astronomers who are also searching for this mystery body, which they call Planet Nine. It was a success: The simulations showed that a distant planet had shepherded 2015 TG387 into its funky orbit.

“This fits in perfectly with what we would predict for Planet Nine, so I’m happy to see it discovered,” says Brown, the Caltech astronomer. (Brown, coincidentally, is among those responsible for Pluto’s reclassification; he discovered many large objects beyond Neptune that made scientists rethink their definition of planets.)

Batygin was also excited. “I’m running code as we speak that evaluates how the inferred orbit and mass of [the hypothetical planet] are affected by this new object,” he said, when I contacted him the day before the discovery was announced.
Aside from its elongated orbit, little is known about 2015 TG387. The object is too far for astronomers to determine its composition or color. “It’s a point of light, it’s clear, it’s there, but it’s very faint,” Sheppard said.
Based on the little light they can see, Sheppard and his team estimate the object is about 300 kilometers (186 miles) across, which would make it a smallish dwarf planet.

The researchers think there could be thousands of small bodies like 2015 TG387 at the edge of the solar system. But finding them isn’t easy. For about 99 percent of its orbit, 2015 TG387 is too faint for our most powerful telescopes to detect. Astronomers only caught it when it made its closest approach to the sun.

And even then: “At the closest point in its orbit, this object is still more than two times farther from the sun than Neptune, which is pretty remarkable,” says Juliette Becker, an astronomer at the University of Michigan and a fellow hypothetical-planet hunter who was not involved in the study. “Objects at this distance are extremely hard to discover.”

Astronomers need to find more of these objects to sharpen their search for a new neighbor in our solar system. Their strange orbits reveal clues about the gravitational forces acting on them, which in turn provide information about the location of the hypothetical planet.

Or maybe not. The hypothetical-planet theory has its critics. They chalk it up to observational bias, the human tendency to see things that we expect or want to see. They suggest that one of the arguments for this mystery planet, the strange clustering of objects beyond Neptune, may not be that strange at all. Astronomers have only surveyed a fraction of the sky in their search; perhaps the pattern they’ve spotted in one slice of the solar system only looks like a pattern because they can’t see the rest, and these objects might actually be evenly distributed.

 

[Bat-mite]

Crazy stuff! Batygin ... that's a cool name. I wonder if there is a Supyvodka and a Spidyrum?

I wonder how many years/decades it will take to really know if this things are there or what they are.

 

[jd2cylman]

Planet 9 already has a name. Pluto... Thbttt...

 

[Winston]

Why astronomers now doubt there is an undiscovered 9th planet in our solar system
26 May 2020

https://phys.org/news/2020-05-astronomers-undiscovered-9th-planet-solar.html
Mathematical calculations and detailed computer simulations have shown that the orbits we see in the Kuiper Belt can only have been created if Neptune originally formed a few AU closer to the sun, and migrated outward to its present orbit. Neptune's migration explains the pervasiveness of highly elliptical orbits in the Kuiper Belt, and can explain all the KBO orbits we've observed, except for a handful of KBOs on extreme orbits that always stay at least 10 AU beyond Neptune.

All of the extreme KBOs that had been discovered prior to OSSOS and DES were from surveys that did not fully report their directional biases. So we do not know if all these KBOs were discovered in the same quadrant of the solar system because they are actually confined, or because no surveys searched deep enough in the other quadrants. We performed additional simulations that showed that if observations are made only in one season from one telescope, extreme KBOs will naturally only be discovered in one quadrant of the solar system.

Further testing the Planet Nine theory, we looked in detail at the orbits of all known "extreme" KBOs and found that all but the two highest pericentre KBOs can be explained by known physical effects. These two KBOs are outliers, but our previous detailed computer simulations of the Kuiper Belt, which included gravitational effects from Planet Nine, produced a set of "extreme" KBOs with pericentres smoothly ranging from 40 to over 100 AU.

These simulations predict that there should be many KBOs with pericentres as large as the two outliers, but also many KBOs with smaller pericentres, which should be much easier to detect. Why don't the orbit discoveries match the predictions? The answer may be that the Planet Nine theory does not hold up to detailed observations.

 

[Funkworks]

Once I get my Level 642 certification, I'm going up there in person to sort this out once and for all.