Sentences with phrase «leoville chondrite»

A recent analysis of chondrites by Carnegie's Myriam Telus was concerned with iron - 60, a short - lived radioactive isotope that decays into nickel - 60.

Measuring the amount of these daughter isotopes can tell scientists when, and possibly how, the chondrites formed.

But carbonaceous chondrites are known to have formed later than other meteorites — so it was possible that their peculiar isotopic chemistry reflected changes over time in the disk, rather than a distinct place of origin.

Like a chemical fingerprint, the isotopic ratio between Earth's samples and the carbonaceous chondrites» samples matched.

Some of that water was contained as ice in primitive meteorites called carbonaceous chondrites.

Using a new analytical technique, the team looked at different kinds of chondrite meteorites, a type of primitive meteorite approximately 4.6 billion years old.

The cores of the worlds studied by Bouquet and his co-authors are thought to have chondrite - like compositions.

Radioactive isotopes of elements such as uranium, potassium, and thorium are found in a class of rocky meteorites known as chondrites.

These results show also that Mercury likely formed with enstatite chondrites.

The characterization of Annama indicates that this is an ordinary H5 chondrite, a group of meteorites with high strength that constitutes 31 % of meteorite falls.

The vast majority are chondrites, pieces of asteroids filled with little glassy beads called chondrules.

The stone's noble gas content supports an extraterrestrial origin, while the presence of tiny diamonds — larger than nanodiamonds found in a common kind of meteorite called chondrites, but similar in size to diamond aggregates known to be formed by impacts — supports a cometary origin.

Water and other volatile elements arrived on Earth via meteorites called carbonaceous chondrites.

McCord's grad students set to work on the data and came up with some preliminary findings: Ceres was a carbonaceous chondrite (a type of asteroid composed of water locked in minerals and carbon - based materials), and it had not been thermally altered.

Almost on a whim, Piatek paid $ 6000 for the stone — cheap in the meteorite world — thinking it was nothing more than a regular chondrite.

Though the cometary region is now ruled out, the exact birthplace of the carbonaceous chondrites is far from certain, says Fred Ciesla, a researcher at the University of Chicago.

It didn't have the heft of a chondrite, which are typically rich in dense metals.

Microscopic analyses of chondrites, the oldest rocks in the solar system, are filling in details of what our neighborhood in space was like shortly before the planets formed

Or, the proto - moon and proto - Earth were showered by the same family of carbonaceous chondrites soon after they separated, said James Van Orman, professor of earth, environmental and planetary sciences at Case Western Reserve, and a co-author.

The investigators found that the deuterium / hydrogen ratio in the melt inclusions was relatively low and matched the ratio found in carbonaceous chondrites.

In total, the effects proved to be small for the melt inclusions, and the ratios remained consistent with the those of the chondrites.

This abundance is lower than model estimates of ultraviolet (UV) degradation of accreted interplanetary dust particles (IDP's) or carbonaceous chondrite material.

Stony meteorites, or chondrites — such as this fragment of the Axtell meteorite, found in Texas in 1943 — are among the most common larger pieces.

Most knowledge about the first solid bodies in the solar system comes from meteorites called carbonaceous chondrites, thought to be chunks of the first asteroids.

On his desk at ASU are some polished slices of NWA 6991, a speckled, black stone known as a carbonaceous chondrite: the most primitive type of meteorite containing some of the first material from the solar system's youth.

Early accretion of water in the inner solar system from a carbonaceous chondrite - like source.

Edwin Thompson holds a large slice of enstatite chondrite meteorite that fell in Alberta, Canada, in 1952.

The meteorite's composition matches that of an LL chondrite, — the LL stands for Low iron, Low metals.

«The carbonaceous chondrites don't really work.»

This suggests that the value of K / U ≈ 1 X 104 is characteristic of terrestrial materials and is distinct from the value of 8 X 104 found in chondrites.

They moreover show that the light signature emitted by Phobos and Deimos is incompatible with that of the primordial matter that formed Mars (meteorites such as ordinary chondrite, enstatite chondrite and / or angrite).

There is one other LL chondrite whose orbit is known: the asteroid Itokawa, which the Japanese Hayabusa spacecraft visited in 2005.

For one, the new data throw a wrench in the conventional story that carbonaceous chondrites — a water - rich variety of asteroid — delivered water to an initially dry Earth after its formation.

One thing was odd about Chelyabinsk compared to other LL chondrites: it was shot through with cracks that had filled in with molten metal.

This will permit the average terrestrial concentrations of uranium and thorium to be 2 to 4.7 times higher than that observed in chondrites.

But the chondrite signatures are too heavy to explain the deep Earth samples, Hallis says.

Deimos is composed of rock rich in carbonaceous material, much like C - type asteroids and carbonaceous chondrite meteorites.

He might ask, «What's the range of iron content in the ordinary chondrites?»

The 1,100 - pound (500 kilogram) meteorite is an ordinary H5 chondrite, a type of stony meteorite responsible for 31 percent of Earth's impacts.

It appears similar to a group of asteroids known as carbonaceous chondrites.

Scientists have speculated that a rain of carbonaceous chondrites may have seeded early Earth with the raw material for biology here.

Based on data obtained with the Gamma Ray and Neutron Detector aboard the Dawn spacecraft, Prettyman et al. (p. 242, published online 20 September) show that Vesta's reputed volatile - poor regolith contains substantial amounts of hydrogen delivered by carbonaceous chondrite impactors.

Physicist John Remo holds a slice of the Leoville chondrite, a meteorite billions of years old.

They found the closest match to be an enstatite chondrite, an extremely rare form of meteorite that is thought to make up only about 2 percent of the meteorites that fall to Earth.

Meteorites such as these carbonaceous chondrites are thought to have delivered water to the Earth — but an outstanding question is when.

«We now know something like an enstatite chondrite was the starting material for Mercury, which is surprising, because they are about 10 standard deviations away from all other chondrites,» Grove says.

They also determined, based on this rapid cooling rate and the composition of lava deposits on Mercury's surface, that the planet likely has the composition of an enstatite chondrite — a type of meteorite that is extremely rare here on Earth.

The study's authors knew the ratio for carbonaceous chondrites and reasoned that if they could compare that to an object that was known to crystallize while Earth was actively accreting then they could gauge when water appeared on Earth.

Two possible ways that the inner solar system received water are: water molecules sticking to dust grains inside the «snow line» (as shown in the inset) and carbonaceous chondrite material flung into the inner solar system by the effect of gravity from protoJupiter.

That, combined with nitrogen isotope data, points to carbonaceous chondrites as the most likely common source of water.