Sentences with phrase «sized planetesimals»

Debris disks contain the solid remnants of planet formation that are in collisional cascade, with particles ranging from kilometre - sized planetesimals down to micron - sized dust grains.

City - size planetesimals — rocky microworlds that clumped together in the solar nebula — smashed into our planet's surface at incredible velocities and seeped down to Earth's iron core, depositing yet more iron.

On January 15, 2010, a team of astronomers released the results of computer simulations indicating that kilometer - size planetesimals can form and accrete into rocky Earth - size planets around Alpha Centauri B despite gravitational perturbations from Alpha Centauri A.

Not exact matches

The dust grains in the disk collide and aggregate to form pebbles, which grow into boulders, and so on increasing in size through planetesimals, planetary embryos, and finally rocky terrestrial planets.

The gravitational forces of these spiral arms could scatter outward the problematic boulder - sized bodies, allowing them to accumulate rapidly to form planetesimals large enough that gas drag is no longer a problem.

The second idea argues that swarms of centimeter - sized pebbles almost instantaneously collapsed under their collective weight to create planetesimals hundreds of kilometers across.

The fact that none were just a few kilometers across undercuts the any - size - goes theory of gradual planetesimal formation, Walsh and colleagues argue.

If too many particles in this size range were lost, there wouldn't be enough remaining to collide with each other and accumulate into planetesimals and, eventually, planets.

By aggregating the sizes of the modern dark asteroids, researchers suggest the original dark planetesimals formed about 4 billion years ago, making this one of the oldest asteroid families in the main belt; most asteroid families are thought to have formed about 1 billion years ago.

In contrast to earlier observations the team did not observe dust that will later form into planets, but dust created in collisions between small planets of a few kilometres in size — objects called planetesimals that are similar to the asteroids and comets of the Solar System.

At that point gravity takes over, pulling in other planetesimals and vacuuming up dust and gas until planet - sized bodies take shape.

Dr Michele Bannister said: «We've discovered that this is a planetesimal with a well - baked crust that looks a lot like the tiniest worlds in the outer regions of our solar system, has a greyish / red surface and is highly elongated, probably about the size and shape of the Gherkin skyscraper in London.

The processes that convert these tiny grains, each a few millionths of a metre (a micron) across, into aggregates a few centimetres in size, and the mechanism for making kilometre - sized «planetesimals» into planetary cores, are both well understood.

The Kuiper Belt hosts a swarm of distant, icy objects ranging in size from small, primordial planetesimals to much larger, highly evolved objects, representing a whole new class of previously unexplored cryogenic worlds.

Swarms of boulder - size objects called planetesimals slowly accreted to form the rocky planets — Mercury, Venus, Earth, and Mars — and their various and sundry satellites.

The traps then allow the pebbles to aggregate to form planetesimals, and eventually planet - sized worlds.

I study the early stages of planet formation, where microscopic dust particles coagulate to form planetesimal - size bodies.

But until then we have a handful of roughly Pluto - sized objects residing in the Kuiper belt that stand out amongst the sea of the planetesimals residing beyond Neptune.

That's why a number of ideas have been proposed recently for speeding up core formation, by efficient accretion of either cm - or mm - sized «pebbles» early on, or small fragments and debris resulting from planetesimal collisions at later stages.