Subscribe free to our newsletters via your
. Space Travel News .




IRON AND ICE
A 2015 Rendezvous With Dwarf Planet Ceres
by Dr. Marc Rayman for Dawn News
Pasadena CA (JPL) Jun 04, 2013


Ceres by Hubble 2004.

Traveling from one alien world to another, Dawn is reliably powering its way through the main asteroid belt with its ion propulsion system. Vesta, the fascinating and complex protoplanet it explored in 2011 and 2012, falls farther and farther behind as the spacecraft gently and patiently reshapes its orbit around the sun, aiming for a 2015 rendezvous with dwarf planet Ceres.

The stalwart adventurer has recently completed its longest uninterrupted ion thrust period yet. As part of the campaign to conserve precious hydrazine propellant, Dawn now suspends thrusting once every four weeks to point its main antenna to Earth. (In contrast, spacecraft with conventional chemical propulsion spend the vast majority of time coasting.)

Because of details of the mission operations schedule and the schedule for NASA's Deep Space Network, the thrust durations can vary by a few days. As a result, the spacecraft spent 31.2 days thrusting without a hiatus.

This exceeds Deep Space 1's longest sustained powered flight of 29.2 days. While there currently are no plans to thrust for longer times, the unique craft certainly is capable of doing so. The principal limitation is how much data it can store on the performance of all subsystems (pressures, temperatures, currents, voltages, valve positions, etc.) for subsequent reporting to its terrestrial colleagues.

Thanks to the ship's dependability, the operations team has been able to devote much of its energies recently to developing and refining the complex plans for the exploration of Ceres. You might be among the privileged readers who will get a preview when we begin describing the plans later this year.

Controllers also have devised some special activities for the spacecraft to perform in the near future, accounts of which are predicted to be in the next two logs.

In addition, team members have had time to maintain their skills for when the spacecraft needs more attention. Earlier this month, they conducted an operational readiness test (ORT). One diabolical engineer carefully configured the Dawn spacecraft simulator at JPL to behave as if a pebble one-half of a centimeter (one-fifth of an inch) in diameter shooting through the asteroid belt collided with the probe at well over twice the velocity of a high-performance rifle bullet.

When the explorer entered this region of space, we discussed that it was not as risky as residents of other parts of the solar system might assume. Dawn does not require Han Solo's piloting skills to avoid most of the dangerous rocky debris.

The robot could tolerate such a wound, but it would require some help from operators to resume normal operations. This exercise presented the spacecraft team with an opportunity to spend several days working through the diagnosis and performing the steps necessary to continue the mission (using some of the ship's backup systems). While the specific problem is extremely unlikely to occur, the ORT provided valuable training for new members of the project and served to keep others sharp.

One more benefit of the smooth operations is the time that it enables your correspondent to write his third shortest log ever. (Feel free to do the implied research.) Frequent readers can only hope he strives to achieve such a gratifying feat again!

Dawn is 13 million kilometers (7.9 million miles) from Vesta and 54 million kilometers (34 million miles) from Ceres. It is also 3.25 AU (486 million kilometers or 302 million miles) from Earth, or 1,275 times as far as the moon and 3.20 times as far as the sun today. Radio signals, traveling at the universal limit of the speed of light, take 54 minutes to make the round trip.

.


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






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




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





IRON AND ICE
Large asteroid completes Earth flyby
Pasadena, Calif. (UPI) Jun 1, 2013
A 1.7-mile-wide asteroid whose moon alone had the potential to cripple life on Earth passed safely by under the close watch of scientists, NASA said. The massive rock, known as 1998 QE2, came within 3.6 million miles of smashing into Earth before continuing into deep space, CNN reported. The asteroid has its own satellite that is about 2,000 feet across. Astronomers never ... read more


IRON AND ICE
The Future of Space Launch

Rocket Engine Maker Proton-PM to Invest in New Products

Russia Launches European Telecoms Satellite

Ariane poised to launch first 20 ton payload into orbit

IRON AND ICE
Mars Curiosity Rover Provides Strong Evidence for Flowing Water

Ten Years At Mars: New Global Views Plot History Of The Red Planet

Flowing Water Transported Sand, Rocks Along Martian Streambed

Leicester Scientist Helps Discover Ancient Streambed On Mars

IRON AND ICE
NASA's GRAIL Mission Solves Mystery of Moon's Surface Gravity

Moon dust samples missing for 40 years found in Calif. warehouse

Unusual minerals in moon craters may have been delivered from space

Moon being pushed away from Earth faster than ever

IRON AND ICE
Planning Accelerates For Pluto Encounter

'Vulcan' wins Pluto moon name vote

Public to vote on names for Pluto moons

The PI's Perspective: The Seven-Year Itch

IRON AND ICE
In feat, telescope directly spots lightweight exoplanet

Scouting for Not-So-Distant Worlds

Lightest exoplanet imaged so far?

Big Weather on Hot Jupiters

IRON AND ICE
Boeing Completes Commercial Crew Spacecraft And Rocket Milestones

Girl expelled from school for exploding experiment going to space camp

New method for producing clean hydrogen

Adapter 'Flips' for Progress Toward 2014 Exploration Flight Test

IRON AND ICE
Shenzhou-10 spacecraft to be launched in mid-June

Sizing Up Shenzhou 10

Rollout for Shenzhou 10

Soft Pedal for Shenzhou 10

IRON AND ICE
Large asteroid completes Earth flyby

A 2015 Rendezvous With Dwarf Planet Ceres

New Images of Comet ISON Hurtling Toward the Sun

NASA Radar Reveals Asteroid Has Its Own Moon




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. 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 Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement