Collective gravity, not Planet Nine, may explain the orbits of 'detached objects'

June 4, 2018, University of Colorado at Boulder
Credit: CC0 Public Domain

Bumper car-like interactions at the edges of our solar system—and not a mysterious ninth planet—may explain the dynamics of strange bodies called "detached objects," according to a new study.

CU Boulder Assistant Professor Ann-Marie Madigan and a team of researchers have offered up a new theory for the existence of planetary oddities like Sedna. This minor planet orbits Earth's sun at a distance of 8 billion miles but appears separated from the rest of the solar system.

One theory for its unusual dynamics is that an as-of-yet-unseen ninth planet beyond Neptune may have disturbed the orbits of Sedna and other detached objects. But Madigan and her colleagues calculated that the orbits of Sedna and its ilk may result from these bodies jostling against each other and space debris in the outer solar system.

"There are so many of these bodies out there. What does their collective gravity do?" said Madigan of the Department of Astrophysical and Planetary Sciences (APS) and JILA. "We can solve a lot of these problems by just taking into account that question."

The researchers will present their findings on June 4 at a press briefing at the 232nd meeting of the American Astronomical Society, which runs from June 3-7 in Denver.

Detached objects like Sedna get their name because they complete humongous, that bring them nowhere close to big planets like Jupiter or Neptune. How they got to the outer solar system on their own is an ongoing mystery.

Using computer simulations, Madigan's team came up with one possible answer. Jacob Fleisig, an undergraduate studying astrophysics at CU Boulder, calculated that these icy objects the sun like the hands of a clock. The orbits of smaller objects, such as asteroids, however, move faster than the larger ones, such as Sedna.

"You see a pileup of the orbits of smaller objects to one side of the sun," said Fleisig, who is the lead author of the new research. "These orbits crash into the bigger body, and what happens is those interactions will change its orbit from an oval shape to a more circular shape."

In other words, Sedna's orbit goes from normal to detached entirely because of those small-scale interactions. The team's observations also fall in line with research from 2012, which observed that the bigger a detached gets, the farther away its orbit becomes from the sun. Alexander Zderic, a graduate student in APS at CU Boulder, also co-authored the new research.

The findings may also provide clues around another phenomenon: the extinction of the dinosaurs. As interacts in the outer solar system, the orbits of these objects tighten and widen in a repeating cycle. This cycle could wind up shooting comets toward the inner solar system—including in the direction of Earth—on a predictable timescale.

"While we're not able to say that this pattern killed the dinosaurs," Fleisig said, "it's tantalizing."

Explore further: How we discovered 840 minor planets beyond Neptune – and what they can tell us

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rrwillsj
1 / 5 (2) Jun 04, 2018
Interesting conjectures from analyzing new evidence.

I wonder if visualized from a distance. Above the plane of planetary rotation. If there would be a slow-motion wave visible, rotating around the Solar System?
JamesG
2.2 / 5 (5) Jun 04, 2018
We won't know until we get an observatory out there. Scientists need to stop chasing little green men and start giving more support to space travel so they can get out there themselves. It's to their benefit to stop complaining every time some money gets moved from their favorite project to space travel. Support something that will get the rest of the world excited (not little green men or microbes on Europa) and it will speed up the time before they get to look from a much better vantage point.
baudrunner
1 / 5 (7) Jun 04, 2018
Computer simulations based on a paradigm. What is observed are what are being called perturbations of the orbits of the outer planets that we presume can only be caused by a large planetary body about four times the mass of Earth, because the paths of these planets defy the predicted trajectories based on what is understood about gravitation. What perhaps we are not realizing is that massive bodies like the planets have inertia, and notwithstanding the fact that gravity acts instantaneously, it will still take thousands of years for the effects of the close encounters of Planet 9 through our solar system to subside so that we realize a state of equilibrium among the orbiting planets. It is my considered opinion that Planet 9 finally collided with Sol, and that this happened after Joshua's long day, when Planet 9 passed through our orbit and temporarily suspended our rotation in sync with the sun's apparent position in the sky. I think it got pulled, no spiraled, in.

Or not.
24volts
1 / 5 (7) Jun 04, 2018
I'm really surprised that none of them are trying to say it's caused by 'dark matter'. That seems to be the preferred explanation for anything they don't know the answer to these days.
Mimath224
5 / 5 (3) Jun 04, 2018
@JamesG
We won't know until we get an observatory out there. Scientists need to stop chasing little green men and start giving more support to space travel so they can get out there themselves. It's to their benefit to stop complaining every time some money gets moved from their favorite project to space travel. Support...excited (not little green men or microbes on Europa) and it will speed up the time before they get to look from a much better vantage point.

Ha, Maybe it is 'little green men' playing marbles with the solar system. Seriously though, I would have thought (I don't actually know) that the increases in military budgets the world over overshadows the budgets used for the search for life. Rather a campaign for less military spending would be more productive. But before you say so, I know THAT isn't going to happen. The country in which I spend the majority of my time has much poverty yet the government wants to spend billions on a security satellite.
rrwillsj
2 / 5 (4) Jun 04, 2018
James, I do not believe that human space travel is either safe or economical or worth the resources and funding to pursue. If we wanted to really get sirius about space exploration. Robots constructing automated facilities on Luna to produce and launch fleets of reconnaissance drones. would not only be a lot more economical. But collect a lot more data than even a thousand astronauts could accomplish.

bawd, the Sumerians are calling. Demanding that you return their mythology that you have plagiarized. Badly...

24v, Please, oh please! Suggest some other names for the almost incoherent terms: Dark Matter, Black Hole. Big Bang. You'd be my hero if you could sell the new terms to becoming popularly accepted memes! Just remember, "Hope springs infernal!"

Zorcon
3 / 5 (2) Jun 04, 2018
I'm really surprised that none of them are trying to say it's caused by 'dark matter'. That seems to be the preferred explanation for anything they don't know the answer to these days.

It is caused by 'dark matter.' But in this case they are able to narrow the dark matter down to large baryonic bodies such as minor planets and/or planet nine. So nobody is going to use the more general term 'dark matter.'

Dark matter = any matter which has so far been detected only by its gravitational effects. Unfortunately there don't seem to be enough undiscovered planet-like objects (such as MACHOs) to account for all of it.

Dark matter is not meant to be an explanation for anything. It's more like a placeholder for things we haven't found yet.
Zorcon
3 / 5 (2) Jun 04, 2018
We won't know until we get an observatory out there. Scientists need to stop chasing little green men and start giving more support to space travel so they can get out there themselves. It's to their benefit to stop complaining every time some money gets moved from their favorite project to space travel. Support something that will get the rest of the world excited (not little green men or microbes on Europa) and it will speed up the time before they get to look from a much better vantage point.


One star for "Scientists need to stop chasing little green men..." (we should keep looking, it doesn't cost much and the results - either way - will be invaluable and awe inspiring).

Five stars for "start giving more support to space travel!"
rrwillsj
1 / 5 (3) Jun 05, 2018
Z, you use the term "space travel". It sounds like you meant it as a euphemism for "human space travel"?

If so, aside from limited space transportation publicly subsidized by taxpayers. Or stockholder subsidies for corporate promotional stunt extravaganzas.

The only probable space travel will be very costly, ego-tripping into orbit for the wealthy playing at spaceman boasting.

Come to think of it though, if we could convince all the plutocracy to journey to the Moon? They could prove useful as feedstock for the cannibal-zombie-robots.

Yeah, finally found a use for the useless creatures!
yaridanjo
1 / 5 (2) Jun 30, 2018
Here is the mass and orbital parameter of a Jovian sized body in our outer solar system. It's period has been verified in several ways and some of its otherorbital parameters are close to what astronomer Forbes found in 1880. We called in Ulsan when we found it in the 2002-2004 time frame:
http://barry.warm...led.html
VULCAN REVEALED
A Dangerous New Jovian Sized Body In Our Solar System

yaridanjo
1 / 5 (2) Jun 30, 2018
Here is the mass and orbital parameter of a Jovian sized body in our outer solar system. It's period has been verified in several ways and some of its otherorbital parameters are close to what astronomer Forbes found in 1880. We called in Vulcan when we found it in the 2002-2004 time frame:
http://barry.warm...led.html
VULCAN REVEALED
A Dangerous New Jovian Sized Body In Our Solar System
yaridanjo
1 / 5 (2) Jun 30, 2018
Here is the mass and orbital parameter of a Jovian sized body in our outer solar system. It's period has been verified in several ways and some of its otherorbital parameters are close to what astronomer Forbes found in 1880. We called it Vulcan when we found it in the 2002-2004 time frame:
http://barry.warm...led.html
VULCAN REVEALED
A Dangerous New Jovian Sized Body In Our Solar System

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