. 24/7 Space News .
NASA Spacecraft Is A Go For Asteroid Belt

Dawn's science instrument suite will measure mass, shape, surface topography and tectonic history, elemental and mineral composition, as well as seek out water-bearing minerals.
by Staff Writers
Cape Canaveral FL (SPX) Sep 26, 2007
Launch and flight teams are in final preparations for the planned Sept. 27 liftoff from Pad 17-B at Cape Canaveral Air Force Station, Fla., of NASA's Dawn mission. The Dawn spacecraft will venture into the heart of the asteroid belt, where it will document in exceptional detail the mammoth rocky asteroid Vesta, and then, the even bigger icy dwarf planet Ceres.

"If you live in the Bahamas this is one time you can tell your neighbor, with a straight face, that Dawn will rise in the west," said Dawn Project Manager Keyur Patel of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Weather permitting, we are go for launch Thursday morning -- a little after dawn."

Dawn's Sept. 27 launch window is 7:20 to 7:49 a.m. Eastern Daylight Time (4:20 to 4:49 a.m. Pacific Daylight Time). At the moment of liftoff, the Delta II's first-stage main engine along with six of its nine solid-fuel boosters will ignite. The remaining three solids are ignited in flight following the burnout of the first six. The first-stage main engine will burn for 4.4 minutes. The second stage will deposit Dawn in a 185-kilometer-high (100- nautical-mile) circular parking orbit in just under nine minutes. At about 56 minutes after launch, the rocket's third and final stage will ignite for approximately 87 seconds. When the third stage burns out, actuators and push-off springs on the launch vehicle will separate the spacecraft from the third stage.

"After separation, the spacecraft will go through an automatic activating sequence, including stabilizing the spacecraft, activating flight systems and deploying Dawn's two massive solar arrays," said Patel. "Then and only then will the spacecraft energize its transmitter and contact Earth. We expect acquisition of signal to occur anywhere from one-and-a-half hours to three-and-a-half hours after launch."

The Dawn mission will explore Vesta, and later Ceres, because these two asteroid belt behemoths have been witness to so much of our solar system's history.

"Visiting both Vesta and Ceres enables a study in extraterrestrial contrasts," said Dawn Principal Investigator Christopher Russell of the University of California, Los Angeles. "One is rocky and is representative of the building blocks that constructed the planets of the inner solar system. The other may very well be icy and represents the outer planets. Yet, these two very diverse bodies reside in essentially the same neighborhood. It is one of the mysteries Dawn hopes to solve."

Using the same spacecraft to reconnoiter two different celestial targets makes more than fiscal sense. It makes scientific sense. By utilizing the same set of instruments at two separate destinations, scientists can more accurately formulate comparisons and contrasts. Dawn's science instrument suite will measure mass, shape, surface topography and tectonic history, elemental and mineral composition, as well as seek out water-bearing minerals. In addition, the Dawn spacecraft itself and the way it orbits both Vesta and Ceres will be used to measure the celestial bodies' gravity fields.

"Understanding conditions that lead to the formation of planets is a goal of NASA's mission of exploration," said David Lindstrom, Dawn program scientist at NASA Headquarters, Washington. "The science returned from Vesta and Ceres could unlock many of the mysteries of the formation of the rocky planets including Earth."

Before all this celestial mystery unlocking can occur, Dawn has to reach the asteroid belt and its first target - Vesta. This is a four-year process that begins with launch and continues with the firing of three of the most efficient engines in NASA's space motor inventory - ion propulsion engines. Employing a complex commingling of solar-derived electric power and xenon gas, these frugal powerhouses must fire for months at a time to propel as well as steer Dawn. Over their eight-year, almost 4-billion-mile lifetime, these three ion propulsion engines will fire cumulatively for about 50,000 hours (over five years) - a record for spacecraft.

The Dawn mission to asteroid Vesta and dwarf planet Ceres is managed by JPL, for NASA's Science Mission Directorate, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena. The University of California, Los Angeles, is responsible for overall Dawn mission science. Other scientific partners include: Los Alamos National Laboratory, New Mexico; Max Planck Institute for Solar System Research, Katlenburg, Germany; and Italian National Institute of Astrophysics, Rome. Orbital Sciences Corporation of Dulles, Va., designed and built the Dawn spacecraft.

Community
Email This Article
Comment On This Article

Related Links
Dawn
Asteroid and Comet Mission News, Science and Technology



Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News


MIT Tether Could Aid Asteroid Missions
Boston MA (SPX) Sep 26, 2007
Using a tether system devised by MIT researchers, astronauts could one day stroll across the surface of small asteroids, collecting samples and otherwise exploring these rocks in space without floating away. The ability to visit asteroids could also be invaluable for testing equipment for a mission to Mars by humans. Further, knowing how to tether an asteroid could be helpful if one needs to be towed away from a potential collision course with Earth, says Christopher Carr, a postdoctoral associate in MIT's Department of Earth, Atmospheric and Planetary Sciences.







  • NASA, NSBRI Select 17 Proposals In Space Radiation Research
  • Space summit looks to the future from India
  • Part-time model is Malaysia's first astronaut
  • Russia aims for new far east space launch pad by 2020

  • Tracing Martian Water
  • MIT Observations Give Precise Estimate Of Mars Surface Ice
  • Mars Gully: No Mineral Trace Of Liquid Water
  • NASA aims to put man on Mars by 2037

  • Pratt And Whitney Rocketdyne's RS-27A Powers New-Gen Imaging Satellite To Orbit
  • United Launch Alliance Launches 75th Consecutive Delta II On USAF 60th Anniversary
  • Arianespace To Launch Japanese Satellite JCSAT-12
  • Russian Space Launch Vehicle Firing Tests Set For 2008

  • Boeing Launches WorldView-1 Earth-Imaging Satellite
  • New Faraway Sensors Warn Of Emerging Hurricane's Strength
  • Key Sensor For Northrop Grumman NPOESS Program Passes Critical Structural Test
  • Air France And ESA Join To Offer Passengers Unique View Of Voyage

  • Outbound To The Outerplanets At 7 AU
  • Charon: An Ice Machine In The Ultimate Deep Freeze
  • New Horizons Slips Into Electronic Slumber
  • Nap Before You Sleep For Your Cruise Into The Abyss Of Outer Sol

  • 'Orphan' Stars Found In Long Galaxy Tail
  • Explosion Reveals Tiny Magnetic Island
  • A World Premiere! The International Dark Sky Reserve Of Mont-Megantic Is Officially Created
  • The Magellanic Clouds Are First-Time Visitors

  • Asian spacefarers race for the moon
  • Outside View: China shoots for the moon
  • NASA Maps The Moon With Google
  • The Promised Moon

  • EU plans for funding Galileo satnav system already hitting snags
  • Galileo GPS Network Hit By More Delays
  • Brussels to present finance plans to save Galileo satnav project
  • DoD Permanently Discontinues Procurement Of Global Positioning System Selective Availability

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2007 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement