Tag Archives: vesta. asteroid

This perspective view of Marcia crater on the giant asteroid Vesta shows the most spectacularly preserved example of "pitted terrain," an unexpected discovery in data returned by NASA's Dawn mission. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/JHUAPL

Hints of water found on the giant space rock Vesta

Two studies conducted by scientists at NASA based on data gathered by the Dawn spacecraft, which orbited around the Vesta asteroid, showed that the giant space rock holds tantalizing signs of water on its surface – albeit in very small amounts, in the form of hydrated minerals.

This perspective view of Marcia crater on the giant asteroid Vesta shows the most spectacularly preserved example of "pitted terrain," an unexpected discovery in data returned by NASA's Dawn mission. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/JHUAPL

This perspective view of Marcia crater on the giant asteroid Vesta shows the most spectacularly preserved example of “pitted terrain,” an unexpected discovery in data returned by NASA’s Dawn mission. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/JHUAPL

These conclusions were drawn after scientists found that volatile, or easily evaporated materials, have colored Vesta’s surface in a broad swath around its equator. Again, concerning its geometry,  peculiar pothole-like features mark some of the asteroid’s surface where the volatiles, likely water, released from hydrated minerals boiled off and eroded the rock. These formations have been found to be extremely similar to those on Mars, however while the planet is known to have been abundant  in water at a time; these feature identified on Vesta, an asteroid, took scientists particularly by surprise.

Again, no actual water was found, but scientists explain that due to the high energy release during collisions with other space rocks, the hydrogen bound to the minerals was converted into water, which instantly evaporated and thus geologically shaped the asteroid. The holes that were left as the water escaped stretch as much as 0.6 miles (1 kilometer) across and go down as deep as 700 feet (200 meters).

“The source of the hydrogen within Vesta’s surface appears to be hydrated minerals delivered by carbon-rich space rocks that collided with Vesta at speeds slow enough to preserve their volatile content,” said Thomas Prettyman, the lead scientist for Dawn’s gamma ray and neutron detector (GRaND) at the Planetary Science Institute in Tucson, Ariz.

At first, the researchers hypothesized that it might be possible for ice water to survive on the surface of the asteroid, at its poles. However,  Vesta has no permanently shadowed polar regions where ice might survive, and is permanently exposed to sunlight in a cyclic fashion.

“These results provide evidence that not only were hydrated materials present, but they played an important role in shaping the asteroid’s geology and the surface we see today.”

The Dawn spacecraft left last month from Vesta’s orbit, which is the 2nd largest rock in the asteroid belt, and is currently heading for the dwarf planet of Ceres – the biggest rock in the asteroid belt.

The findings were described in two papers published in the journal Science.

source

Rainbow-like map of meteor shows planet like features

This rainbow map of the Vesta asteroid was obtained using NASA’s Dawn spacecraft and it shows that it has much more planet-like features than its mates from the asteroid belt.

Vesta is a pretty special place, with lots of surprises; it has a weird history, a mountain 3 times bigger than the Everest, and now, as it turns out, an interesting mineralogy. The colors you see in this image are practically different types of rock; the image was taken with the probe’s framing camera, which was built by the Max Planck Institute for Solar System Research and the German Aerospace Center. It basically picks up different wavelengths emitted by different minerals.

The green colored areas for example suggest wavelengths of iron-rich pyroxen, a silicate found mostly in igneous rocks. This all goes to show Vesta is a diverse object, unlike most other asteroids, and it has well-separated layers – all of which point at it being a protoplanet, an embryonic world which might have become a regular planet, if it hadn’t had the misfortune of being trapped in the lethal asteroid belt.

“The distinct compositional variation and layering that we see at Vesta appear to derive from internal melting of the body shortly after formation, which separated Vesta into crust, mantle and core,” said Carol Raymond, Dawn’s deputy principal investigator at NASA’s Jet Propulsion Laboratory, in a press release. “Vesta’s iron core makes it special and more like terrestrial planets than a garden-variety asteroid.”

The $466-million Dawn spacecraft has been studying Vesta since July this year, and will continue to do so until the summer, when it will move on to Ceres – another protoplanet, and the largest body in the asteroid belt.

Via Wired