Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New NASA supercomputer model shows planet making waves in nearby debris disk

26.06.2015

A new NASA supercomputer simulation of the planet and debris disk around the nearby star Beta Pictoris reveals that the planet's motion drives spiral waves throughout the disk, a phenomenon that causes collisions among the orbiting debris. Patterns in the collisions and the resulting dust appear to account for many observed features that previous research has been unable to fully explain.

"We essentially created a virtual Beta Pictoris in the computer and watched it evolve over millions of years," said Erika Nesvold, an astrophysicist at the University of Maryland, Baltimore County, who co-developed the simulation. "This is the first full 3-D model of a debris disk where we can watch the development of asymmetric features formed by planets, like warps and eccentric rings, and also track collisions among the particles at the same time."


Erika Nesvold and Marc Kuchner discuss how their new supercomputer simulation helps astronomers understand Beta Pictoris.

Courtesy of NASA's Goddard Space Flight Center

In 1984, Beta Pictoris became the second star known to be surrounded by a bright disk of dust and debris. Located only 63 light-years away, Beta Pictoris is an estimated 21 million years old, or less than 1 percent the age of our solar system. It offers astronomers a front-row seat to the evolution of a young planetary system and it remains one of the closest, youngest and best-studied examples today.

The disk, which we see edge on, contains rock and ice fragments ranging in size from objects larger than houses to grains as small as smoke particles. It's a younger version of the Kuiper belt at the fringes of our own planetary system.

Nesvold and her colleague Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Md., presented the findings Thursday during the "In the Spirit of Lyot 2015" conference in Montreal, which focuses on the direct detection of planets and disks around distant stars. A paper describing the research has been submitted to The Astrophysical Journal.

In 2009, astronomers confirmed the existence of Beta Pictoris b, a planet with an estimated mass of about nine times Jupiter's, in the debris disk around Beta Pictoris. Traveling along a tilted and slightly elongated 20-year orbit, the planet stays about as far away from its star as Saturn does from our sun.

Astronomers have struggled to explain various features seen in the disk, including a warp apparent at submillimeter wavelengths, an X-shaped pattern visible in scattered light, and vast clumps of carbon monoxide gas.

A common ingredient in comets, carbon monoxide molecules are destroyed by ultraviolet starlight in a few hundred years. To explain why the gas is clumped, previous researchers suggested the clumps could be evidence of icy debris being corralled by a second as-yet-unseen planet, resulting in an unusually high number of collisions that produce carbon monoxide. Or perhaps the gas was the aftermath of an extraordinary crash of icy worlds as large as Mars.

"Our simulation suggests many of these features can be readily explained by a pair of colliding spiral waves excited in the disk by the motion and gravity of Beta Pictoris b," Kuchner said. "Much like someone doing a cannonball in a swimming pool, the planet drove huge changes in the debris disk once it reached its present orbit."

Keeping tabs on thousands of fragmenting particles over millions of years is a computationally difficult task. Existing models either weren't stable over a sufficiently long time or contained approximations that could mask some of the structure Nesvold and Kuchner were looking for.

Working with Margaret Pan and Hanno Rein, both now at the University of Toronto, they developed a method where each particle in the simulation represents a cluster of bodies with a range of sizes and similar motions.

By tracking how these "superparticles" interact, they could see how collisions among trillions of fragments produce dust and, combined with other forces in the disk, shape it into the kinds of patterns seen by telescopes. The technique, called the Superparticle-Method Algorithm for Collisions in Kuiper belts (SMACK), also greatly reduces the time required to run such a complex computation.

Using the Discover supercomputer operated by the NASA Center for Climate Simulation at Goddard, the SMACK-driven Beta Pictoris model ran for 11 days and tracked the evolution of 100,000 superparticles over the lifetime of the disk.

As the planet moves along its tilted path, it passes vertically through the disk twice each orbit. Its gravity excites a vertical spiral wave in the disk. Debris concentrates in the crests and troughs of the waves and collides most often there, which explains the X-shaped pattern seen in the dust and may help explain the carbon monoxide clumps.

The planet's orbit also is slightly eccentric, which means its distance from the star varies a little every orbit. This motion stirs up the debris and drives a second spiral wave across the face of the disk. This wave increases collisions in the inner regions of the disk, which removes larger fragments by grinding them away. In the real disk, astronomers report a similar clearing out of large debris close to the star.

"One of the nagging questions about Beta Pictoris is how the planet ended up in such an odd orbit," Nesvold explained. "Our simulation suggests it arrived there about 10 million years ago, possibly after interacting with other planets orbiting the star that we haven't detected yet."

Francis Reddy | EurekAlert!

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>