Alien Planet Discovery a Puzzle --Accepted Theory Says "It Can't Exist"
Follow the Daily Galaxy
Add Daily Galaxy to igoogle page AddThis Feed Button Join The Daily Galaxy Group on Facebook Follow The Daily Galaxy Group on twitter
 

« A Moment of Zen (!) --Lewis Black on Google Glass, Robots & Immortality | Main | "The Great Attractor" --Is Something is Pulling Our Region of the Universe Towards a Colossal Unseen Mass? »

June 18, 2013

Alien Planet Discovery a Puzzle --Accepted Theory Says "It Can't Exist"

 

          Twhy_ill_1

A team of researchers has discovered evidence that an extrasolar planet may be forming quite far from its star—- about twice the distance Pluto is from our Sun. Planet formation far away from a small parent star is at odds with the conventional planet-making dogma. Under the most accepted scenario, planets form over tens of millions of years from the slow accretion of dust, rocks, and gas. That happens most easily close to the central star, where orbital timescales are short. Even under a disk instability scenario, in which planets can collapse quickly from the disk, it's not clear such a low mass planet could form. Carnegie Institute astrophysicist Alan Boss, who works on disk instability models, said "If the mass of this suspected planet is as low as it seems to be, this presents a real puzzle. Theory would say that it cannot exist!"

The planet lies inside a dusty, gaseous disk around a small red dwarf TW Hydrae, which is only about 55 percent of the mass of the Sun. The discovery adds to the ever-increasing variety of planetary systems in the Milky Way. This dusty protoplanetary disk is the closest one to us, some 176 light-years away in the constellation Hydra.

The astronomers made Hubble Space Telescope observations over a wide range of wavelengths from visible to near infrared and modeled the color and structure of the disk in a way that has not been done before. They found a deficit of disk material, or partial gap, at about 80 astronomical units (AU) (1 AU is the Earth/Sun distance). Their models indicate that the depression is about 20 AUs wide, just slightly wider than necessary for a planet-opening gap and consistent with a planet of between 6 and 28 Earth masses. The feature is seen at all wavelengths indicating it is structural and not a local compositional difference. The team believes the evidence is strong for planet formation causing the gap.

 

            Tw_hya

 

"TW Hydrae is between 5 and 10 million years old, and should be in the final throes of planet formation before its disk dissipates," remarked coauthor Alycia Weinberger of the Carnegie Institution and principal investigator of the observations. "It is surprising to find a planet only 5 to 10% of Jupiter's mass forming so far out since planets should form faster closer in. In all planet formation scenarios, it's difficult to make a low-mass planet far away from a low mass star."

The goal of these observations was to understand not only whether planets have formed, but also what conditions can result in planet formation and what chemical constituents are available for new planets. Models by coauthor Hannah Jang-Condell, a former Carnegie postdoctoral researcher, showed that the disk was brighter than expected, which indicates that very small dust grains are being lifted high above the midplane. This is surprising because observations with radio telescopes have previously shown that the disk contains dust that has conglomerated into pebbles.

Weinberger designed the observations to be able to detect large water ice grains in the surface layer of the disk. These grains weren't seen, which probably means that they have grown and sunk to the midplane of the disk where they can aggregate into water-rich planets.

Lead author of the study, John Debes of the Space Science Telescope Institute and also a former Carnegie postdoctoral researcher remarked, "Typically, you need pebbles before you can form a planet. So, if there is a planet in the gap and there is no dust larger than a grain of sand farther out, we have provided a challenge for traditional planet formation models."

The Chandra Observatory illustration at the top of the page depicts matter accreting onto TW Hydrae from a circumstellar disk. X-rays are produced as matter from the disk is guided by the star's magnetic field onto one or more hot spots on the surface of the star. On the right, the illustration shows a binary star system's brightest star producing X-rays much as the Sun does, from a hot upper atmosphere or corona. This indicates that any disk around these stars has been greatly diminished or destroyed in ten million years, perhaps by the ongoing formation of planets or by its companion stars.

The research is published in the Astrophysical Journal.

The Daily Galaxy via Carnegie Institute

Image Credit: NASA, ESA, J. Debes (STScI), H. Jang-Condell (University of Wyoming), A. Weinberger (Carnegie Institution of Washington), A. Roberge (Goddard Space Flight Center), and G. Schneider (University of Arizona/Steward Observatory)

Comments

aliens are forming it through manipulation of dark matter?

Trans-Neptunian objects or Oort cloud objects anyone?

Surprised that they are surprised.

There was an interesting article in Scientific American a few years back hypothesizing that planets formed comparatively farther out in the disk and then migrated inward. This would explain hot Jupiters and leave this less of a puzzle. I'm assuming the main reason for the surprise is more for the dynamics expected around low mass stars than the distance of the discovered planet(?) from its primary. (I insert the question mark because this is still tentative, not confirmed.)

Why do scientists who spend theyre lives looking at the unexplainable or unknown always feel they have the right to say somethings impossible.
It's idiotic behavior like that that holds us back.
Open your eyes, soak up some more data, and come back with another theory (theory not being fact!)

Humans can be so dumb at times.

Yeah well this isn't the first time the 'accepted theory' failed... Question is when will the truth be accepted?

Our solar system theory is probably correct just not complete. The reason why this is an odd planet is because the system theory states when a nebula collapses to a sun and proto plane it has a max radius of 100 AU and this is way beyond that.

Well, if theory is to be substantiated this far-out planet is actually forming next to a neutron star we can't see. Probably the next 'discovery' to shock the community.

It's the best thing that can happen (unexpected event or observation supposedly violating theories) - It's the beautiful unexpected that keeps science changing for the better.....and testing theories and either adding to them or demolishing them is the crux of the scientific method, no?
I love the way we're seeing further into the macrocosm and the microcosm every day - "What a glorious time to be free" indeed!

https://www.youtube.com/watch?v=0PfBYsII_Jw

Ha those xweetok beings...


Post a comment

« A Moment of Zen (!) --Lewis Black on Google Glass, Robots & Immortality | Main | "The Great Attractor" --Is Something is Pulling Our Region of the Universe Towards a Colossal Unseen Mass? »




1


2


3


4


5


6


7


8





9


11


12


13


14


15

Our Partners

technology partners

A


19


B

About Us/Privacy Policy

For more information on The Daily Galaxy and to contact us please visit this page.



E