Space

April 26, 2013

NASA probe observes meteors colliding with Saturn’s rings

nasa-saturn
NASA’s Cassini spacecraft has provided the first direct evidence of small meteoroids breaking into streams of rubble and crashing into Saturn’s rings.

These observations make Saturn’s rings the only location besides Earth, the moon, and Jupiter where scientists and amateur astronomers have been able to observe impacts as they occur. Studying the impact rate of meteoroids from outside the Saturn system helps scientists understand how different planet systems in the solar system formed.

Our solar system is full of small, speeding objects. Planetary bodies frequently are pummeled by them. The meteoroids at Saturn range from about one-half inch to several yards (1 centimeter to several meters) in size. It took scientists years to distinguish tracks left by nine meteoroids in 2005, 2009 and 2012.

Details of the observations appear in a paper in the Thursday edition of Science.

Results from Cassini already have shown Saturn’s rings act as very effective detectors of many kinds of surrounding phenomena, including the interior structure of the planet and the orbits of its moons. For example, a subtle but extensive corrugation that ripples 12,000 miles (19,000 kilometers) across the innermost rings tells of a very large meteoroid impact in 1983.

“These new results imply the current-day impact rates for small particles at Saturn are about the same as those at Earth – two very different neighborhoods in our solar system, and this is exciting to see,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “It took Saturn’s rings acting like a giant meteoroid detector – 100 times the surface area of the Earth – and Cassini’s long-term tour of the Saturn system to address this question.”

The Saturnian equinox in summer 2009 was an especially good time to see the debris left by meteoroid impacts. The very shallow sun angle on the rings caused the clouds of debris to look bright against the darkened rings in pictures from Cassini’s imaging science subsystem.

“We knew these little impacts were constantly occurring, but we didn’t know how big or how frequent they might be, and we didn’t necessarily expect them to take the form of spectacular shearing clouds,” said Matt Tiscareno, lead author of the paper and a Cassini participating scientist at Cornell University in Ithaca, N.Y. “The sunlight shining edge-on to the rings at the Saturnian equinox acted like an anti-cloaking device, so these usually invisible features became plain to see.”

Tiscareno and his colleagues now think meteoroids of this size probably break up on a first encounter with the rings, creating smaller, slower pieces that then enter into orbit around Saturn. The impact into the rings of these secondary meteoroid bits kicks up the clouds. The tiny particles forming these clouds have a range of orbital speeds around Saturn. The clouds they form soon are pulled into diagonal, extended bright streaks.

“Saturn’s rings are unusually bright and clean, leading some to suggest that the rings are actually much younger than Saturn,” said Jeff Cuzzi, a co-author of the paper and a Cassini interdisciplinary scientist specializing in planetary rings and dust at NASA’s Ames Research Center in Moffett Field, Calif. “To assess this dramatic claim, we must know more about the rate at which outside material is bombarding the rings. This latest analysis helps fill in that story with detection of impactors of a size that we weren’t previously able to detect directly.”

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the Cassini-Huygens mission for NASA’s Science Mission Directorate in Washington. JPL designed, developed and assembled the Cassini orbiter and its two onboard cameras. The imaging team consists of scientists from the United States, England, France and Germany. The imaging operations center is based at the Space Science Institute in Boulder, Colo.




All of this week's top headlines to your email every Friday.


 
 

 

Headlines October 1, 2014

Veterans: Substantial VA staff will face discipline - A substantial number of VA employees will face punishment for the veterans treatment scandal, the new national commander of the American Legion predicted Sept. 30, indicating that the slow pace of discipline has more to do with the hoops the department must jump through than it does a...
 
 

News Briefs October 1, 2014

Egypt president gives army control of arms imports The Egyptian president has amended a law, giving the country’s army control over weapons and ammunition imports. The Sept. 30 statement from the presidency says Abdel-Fattah el-Sissi changed articles stipulating that a permit for weapons’ imports has to be granted by the Interior Ministry, which is in...
 
 
atk-test

ATK successfully tests Orion launch abort motor igniter

NASA and ATK successfully completed a static test of the launch abort motor igniter for the Orion crew capsule’s Launch Abort System. Conducted at ATK’s facility in Promontory, Utah, this test is the next step towa...
 

 
uav-coalition

Small UAV coalition launched to advance commercial use of unmanned aerial vehicles

Leading technology companies Oct. 1 formally announced the formation of the Small UAV Coalition to help pave the way for commercial, philanthropic, and civil use of small unmanned aerial vehicles in the United States and abroad...
 
 
Navy photograph

NAWCWD manned for unmanned systems

Navy photograph A rail launch is performed during Integrator unmanned aerial vehicle testing at Naval Air Warfare Center Weapons Division China Lake, Calif. Naval Air Warfare Center Weapons Division scientists, engineers, techn...
 
 
NASA photograph by Ken Ulbrich

NASA employees go ‘above and beyond’

Courtesy photograph NASA Chief Scientist Albion Bowers, Christopher Miller and Nelson Brown receive the Exception Engineering Achievement Medal at Armstrong Research Center, Edwards Air Force Base, Calif. The prestigious award ...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>