Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA's Dawn Sees Young Face on Giant Asteroid

05.11.2012
Like a Hollywood starlet constantly retouching her make-up, the giant asteroid Vesta is constantly stirring its outermost layer and presenting a young face.

Data from NASA's Dawn mission show that a common form of weathering, which occurs on many airless bodies in the inner solar system like the Moon, does not age Vesta’s outermost layer.


NASA/JPL-Caltech/UCLA/MPS/DLR/PSI/Brown

This image from NASA's Dawn spacecraft shows a close up of part of the rim around the crater Canuleia on the giant asteroid Vesta. Canuleia, about 6 miles (10 kilometers) in diameter, is the large crater at the bottom-left of this image. This close-up image illustrates the structure of the interior of the crater and complex details of the fresh rays across the soil of Vesta. The image was taken by Dawn's framing camera on Dec. 29, 2011, from an altitude of about 130 miles (210 kilometers).

Carbon-rich asteroids have also been splattering dark material on Vesta's surface over a long span of its history. The results are described in two papers reported on Nov. 1 in the journal Nature.

David Williams, an associate research professor in ASU’s School of Earth and Space Exploration, is a co-author of the Nature article on Vesta’s dark material, titled “Dark Material on Vesta: Delivering Carbonaceous Volatile-Rich Materials to Planetary Surfaces.”

“The dark material on Vesta has been a perplexing problem, one we first noticed as Dawn approached Vesta in the summer of 2011,” said Williams, a member of the science team task force investigating the dark material. “Through Dawn’s mission at Vesta, it became clear that the dark material was mostly derived from carbon-rich asteroids that impacted Vesta’s surface.”

Early pictures of Vesta showed a variety of dramatic light and dark splotches on its surface. These light and dark materials were unexpected and show Vesta has a brightness range that is among the largest observed on rocky bodies in our solar system.

“Most of the smaller dark material patches are associated with impact craters, forming dark rays of ejecta spreading outward,” Williams said. “There are also large regions of dark material, whose composition suggests they are derived from carbon-rich asteroids – perhaps from one or more large impacts early in Vesta’s history.”

Dawn scientists suspected early on that bright material is native to Vesta. One of their first theories for the dark material suggested it might come from the shock of high-speed impacts melting and darkening the underlying rocks or from recent volcanic activity.

An analysis of data from Dawn’s visible and infrared mapping spectrometer and the framing camera revealed that distribution of dark material is widespread and occurs in small spots and in diffuse deposits, without correlation to any particular underlying geology. The likely source of the dark material is now shown to be carbon-rich asteroids, which are also believed to have deposited hydrated minerals on Vesta.

To get the amount of darkening we now see on Vesta, Williams and colleagues said, scientists estimate about 300 dark asteroids with diameters between 0.6 to 6 miles (1 and 10 kilometers) likely hit Vesta during the last 3.5 billion years. This would have been enough to wrap Vesta in a blanket of mixed material 3 to 7 feet (1 to 2 meters) thick.

“This perpetual contamination of Vesta with material from elsewhere in the solar system is a dramatic example of an apparently common process that changes many solar system objects,” said Thomas McCord, lead author of the Nature paper, who worked with Williams on this study. “Earth likely got the ingredients for life – organics and water – this way.”

Launched in 2007, Dawn spent more than a year investigating Vesta. It departed in September 2012 and is currently on its way to the dwarf planet Ceres.

Williams is a participating scientist on NASA’s Dawn mission. JPL manages the Dawn mission for NASA’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Ala. The University of California at Los Angeles (UCLA) is responsible for overall Dawn mission science.

Orbital Sciences Corp., Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. The California Institute of Technology, Pasadena, manages JPL for NASA.

For more information about Dawn, visit: http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov.

Skip Derra | Newswise Science News
Further information:
http://www.asu.edu
http://www.nasa.gov/dawn
http://dawn.jpl.nasa.gov

More articles from Physics and Astronomy:

nachricht Smallest transistor worldwide switches current with a single atom in solid electrolyte
17.08.2018 | Karlsruher Institut für Technologie (KIT)

nachricht Protecting the power grid: Advanced plasma switch for more efficient transmission
17.08.2018 | DOE/Princeton Plasma Physics Laboratory

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: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>