Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rocks twirl in remote two-step

18.04.2002


This pair of asteroids is locked in a mutual orbit.
© Nature


One lump of rock is revealed as two in the distant Kuiper belt.

The stand-offish dance of two asteroids at the outer reaches of the Solar System is captivating astronomers. The two rocky objects, discovered locked in mutual orbit, could tell us about the properties of the far-flung Kuiper belt.

Christian Veillet and his team1 studied an object called 1998 WW31 in the Kuiper belt, a sparsely populated region of space beyond the orbit of Neptune. The object was previously thought to be a single rock.



One is in fact two, the team found, using images obtained by the Canada-France-Hawaii Telescope in Hawaii. And the pair follow an unusual elongated, ellipse-shaped orbit which keeps them 20-40,000 km apart. This is considered a very distant partnership for a ’binary object’.

The circling pair, which complete a rotation every 570 days, might offer some vital clues to the composition of rocks in the Kuiper belt. Its extreme distance makes resident objects difficult to study.

If one of the circling bodies eclipses the other, the pair’s size could be estimated and hence their density. Understanding the composition of material in the Kuiper belt - which is thought to contain rubble left over from planet formation - might help to discriminate between different explanations for the formation of the Solar System.

Kuiper-belt binaries are hard to spot, because two small bodies can appear as a single fuzzy blob of reflected sunlight at such long distances. Even if two spots are seen, several images are needed to rule out the possibility that they are two adjacent stars along our line of sight. Veillet and his team carried out such careful analyses before they could confidently claim that 1998 WW31 is indeed a binary.

The elliptical orbit is very different from that of the best known partnership in the Kuiper belt: the outermost planet Pluto and its moon Charon. The binary systems known in the asteroid belt between Mars and Jupiter also stick closer together than 1998 WW31.

The new discovery challenges existing theories of how two asteroid-like bodies can become bound together by their gravitational pull. Researchers are not yet clear why the two rocks have not been ripped apart by interactions with other bodies in the Kuiper belt.

References
  1. Veillet, C. et al The binary Kuiper-belt object 1998 WW31. Nature, 416, 711 - 713, (2002).

PHILIP BALL | © Nature News Service

More articles from Physics and Astronomy:

nachricht Mars 2020 mission to use smart methods to seek signs of past life
17.08.2017 | Goldschmidt Conference

nachricht Gold shines through properties of nano biosensors
17.08.2017 | American Institute of Physics

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

Gold shines through properties of nano biosensors

17.08.2017 | Physics and Astronomy

Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter

17.08.2017 | Earth Sciences

Mars 2020 mission to use smart methods to seek signs of past life

17.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>