Space

September 4, 2012

Dawn spacecraft prepares for trek toward dwarf planet

NASA’s Dawn spacecraft is on track to become the first probe to orbit and study two distant destinations to help scientists answer questions about the formation of our solar system.

The spacecraft is scheduled to leave the giant asteroid Vesta Sept. 5 to start its 2 1/2-year journey to the dwarf planet Ceres.

Dawn began its 3-billion-mile odyssey to explore the two most massive objects in the main asteroid belt in 2007. Dawn arrived at Vesta in July 2011 and will reach Ceres in early 2015. These two members of the asteroid belt have been witness to much of our solar system’s history.

The valuable evidence Dawn gathered from examining the first of these cosmic fossils up close improved our understanding of asteroids and provided context for a future human mission to visit an asteroid.

The spacecraft will spiral away from Vesta as gently as it arrived, using a special, hyper-efficient system called ion propulsion. The ion propulsion system uses electricity to ionize xenon to generate thrust. The 12-inch-wide ion thrusters provide less power than conventional engines but can maintain thrust for months at a time.

“Thrust is engaged and we now are climbing away from Vesta atop a blue-green pillar of xenon ions,” said Marc Rayman, Dawn’s chief engineer and mission director, at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We are feeling somewhat wistful about concluding a fantastically productive and exciting exploration of Vesta, but now we have our sights set on dwarf planet Ceres.”

Dawn provided close-up views of Vesta and unprecedented detail about the giant asteroid. Findings revealed that the asteroid had completely melted in the past, forming a layered body with an iron core. The spacecraft also revealed the collisions Vesta suffered in its southern hemisphere. The asteroid survived two colossal impacts in the last 2 billion years. Without Dawn, scientists would not have known about the dramatic troughs sculpted around Vesta, which are ripples from the two south polar impacts.

“We went to Vesta to fill in the blanks of our knowledge about the early history of our solar system,” said Christopher Russell, Dawn’s principal investigator, based at the University of California, Los Angeles. “Dawn has filled in those pages and more, revealing to us how special Vesta is as a survivor from the earliest days of the solar system. We now can say with certainty that Vesta resembles a small planet more closely than a typical asteroid.”

JPL manages the mission to Vesta and Ceres for NASA’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Ala.

UCLA is responsible for the overall Dawn mission science. Orbital Sciences Corp. of 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 part of the mission’s team.

 




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


 
 

 

Headlines January 28, 2015

News: Panel will propose new military retirement system - The long-awaited report on military compensation set to drop Thursday will propose fundamental changes to military retirement and health care benefits, according to several people familiar with the report. Source: DOD to request $585 billion for fiscal 2016 - The Department of Defense is preparing to submit a...
 
 

News Briefs January 28, 2015

Defense contractor to pay $2 million to settle claims A Northern California defense contractor will pay the federal government $2 million to settle claims about its manufacturing of parts for remote-controlled aircraft. The U.S. Attorney’s Office in Sacramento says Sacramento-based Composite Engineering Inc. agreed to pay the money to end allegations that it artificially inflated...
 
 
Navy photograph

USS Roosevelt marks 200,000 trap

Navy photograph An F/A-18F Super Hornet flown by Capt. Daniel Grieco, commanding officer of the aircraft carrier USS Theodore Roosevelt (CVN 71), and Capt. Benjamin Hewlett, deputy commander of Carrier Air Wing (CVW) 1, complet...
 

 
Navy photograph by PO1 William Larned

USS California returns from maiden deployment

Navy photograph by PO1 William Larned The Virginia-class attack submarine USS California (SSN 781) returns from its maiden deployment to its homeport at Naval Submarine Base New London. Under the command of Cmdr. Shawn Huey, Ca...
 
 
Army photograph

Army proves new watercraft capabilities

Army photograph Marine Corps assets are loaded onto the USNS Sgt. Matej Kocak (T-AK 3005), from an U.S. Army Landing Craft Utility, or LCU, USAV Port Hudson during port operations, at White Beach Naval Base, Jan. 22, 2015. Sold...
 
 

Orbital stockholders approve merger with ATK’s aerospace, defense groups

Orbital Sciences Corporation announced Jan. 27 that at a special meeting, the company’s stockholders voted overwhelmingly to approve the proposed merger with the Aerospace and Defense Groups of Alliant Techsystems Inc., pursuant to the definitive transaction agreement dated April 28, 2014. Approximately 99 percent of the votes cast at the special meeting voted in favor...
 




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>