Dawn mission extended at Ceres

Dawn mission extended at Ceres
This artist concept shows NASA's Dawn spacecraft above dwarf planet Ceres, as seen in images from the mission. Credit: NASA/JPL-Caltech

NASA has authorized a second extension of the Dawn mission at Ceres, the largest object in the asteroid belt between Mars and Jupiter. During this extension, the spacecraft will descend to lower altitudes than ever before at the dwarf planet, which it has been orbiting since March 2015. The spacecraft will continue at Ceres for the remainder of its science investigation and will remain in a stable orbit indefinitely after its hydrazine fuel runs out.

The Dawn flight team is studying ways to maneuver Dawn into a new elliptical orbit, which may take the spacecraft to less than 120 miles (200 kilometers) from the surface of Ceres at closest approach. Previously, Dawn's lowest altitude was 240 miles (385 kilometers).

A priority of the second Ceres mission extension is collecting data with Dawn's gamma ray and neutron spectrometer, which measures the number and energy of gamma rays and neutrons. This information is important for understanding the composition of Ceres' uppermost layer and how much ice it contains.

The spacecraft also will take visible-light images of Ceres' surface geology with its camera, as well as measurements of Ceres' mineralogy with its visible and .

The extended mission at Ceres additionally allows Dawn to be in orbit while the goes through perihelion, its to the Sun, which will occur in April 2018. At closer proximity to the Sun, more ice on Ceres' surface may turn to water vapor, which may in turn contribute to the weak transient atmosphere detected by the European Space Agency's Herschel Space Observatory before Dawn's arrival. Building on Dawn's findings, the team has hypothesized that water vapor may be produced in part from energetic particles from the Sun interacting with ice in Ceres' shallow surface.Scientists will combine data from ground-based observatories with Dawn's observations to further study these phenomena as Ceres approaches perihelion.

The Dawn team is currently refining its plans for this next and final chapter of the mission. Because of its commitment to protect Ceres from Earthly contamination, Dawn will not land or crash into Ceres. Instead, it will carry out as much science as it can in its final planned orbit, where it will stay even after it can no longer communicate with Earth. Mission planners estimate the spacecraft can continue operating until the second half of 2018.

Dawn is the only mission ever to orbit two extraterrestrial targets. It orbited giant asteroid Vesta for 14 months from 2011 to 2012, then continued on to Ceres, where it has been in orbit since March 2015.


Explore further

Dawn sets course for higher orbit

More information: For more information, see dawn.jpl.nasa.gov/mission
Citation: Dawn mission extended at Ceres (2017, October 20) retrieved 19 June 2019 from https://phys.org/news/2017-10-dawn-mission-ceres.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
259 shares

Feedback to editors

User comments

Oct 21, 2017
In 2015 Dawn moved closer down to Ceres. In 2016, it moved up to higher orbits. Now in 2017, it's going back down toward Ceres? These manuevers don't seem to carried out very effeciently or with a long-term plan in mind.

Oct 21, 2017
What, you got something against the Hokey Pokey??

There was no guarantee the mission would be extended or Dawn would continue functioning, so it covered high and low orbit objectives. Now, with the extension, it is going back in - even lower. This made possible by the fuel stingy ion drive.

Oct 21, 2017
They managed to get extra science out of it because they were stingy with the fuel and you think that's a Bad Thing?

Really?

Oct 21, 2017
What I find most amusing is that republicant libertardian whiners complain when someone manages to extend a mission because they did a good job. This is typical republicant libertardian whiner juice. And it's bitter.

Sounds like the republicant libertardian whiners can't do THEIR job. And hope to cover it up by whining.

Getting extra science is bonus. Whining about it is bogus. Get over it, @Fart_A.

Oct 22, 2017
This is absolutely a good decision which, when I was regularly following Dawn's progress, seemed only a pipe-dream. The lower part of the planned elliptical orbit will enable the spacecraft to gather new, or more accurate, information on the composition of the surface and near-surface layers. Which translates to more information on how the solar system, and the bodies within it, formed.

I'm so surprised they still have sufficient hydrazine on board after such a long and complex mission - full marks to the Dawn team for such incredibly efficient management of resources!

Oct 22, 2017
@BA
In 2015 Dawn moved closer down to Ceres. In 2016, it moved up to higher orbits. Now in 2017, it's going back down toward Ceres? These manuevers don't seem to carried out very effeciently [sic] or with a long-term plan in mind.
You very evidently have not been keeping up - go and do some online research and find out just how amazing the Dawn mission has been and, in particular, to understand the careful reasoning behind the different orbits achieved by Dawn around Ceres.

Without doing that, your remarks just make you look foolish - is that really how you want to be seen?

Oct 22, 2017
Beside the chemical analysis, higher res pictures of the structures some degrees off the Occator "white spot" or the Ahuna Mons mountain will make it to global MSN which is always good for NASA.

120 miles (200 kilometers) from the surface of Ceres at closest approach. Previously, Dawn's lowest altitude was 240 miles (385 kilometers).

200=193 | 385=386 I know, petty..

Oct 22, 2017
In 2015 Dawn moved closer down to Ceres. In 2016, it moved up to higher orbits. Now in 2017, it's going back down toward Ceres? These manuevers don't seem to carried out very effeciently or with a long-term plan in mind.

Inas much as it has completed the design/mission objectives, It's now being moved to an even closer orbital path...
Now that that is done, they can be less concerned about how the equipment is deployed. It's a freeby now...

Oct 22, 2017
Beside the chemical analysis, higher res pictures of the structures some degrees off the Occator "white spot" or the Ahuna Mons mountain will make it to global MSN which is always good for NASA.

120 miles (200 kilometers) from the surface of Ceres at closest approach. Previously, Dawn's lowest altitude was 240 miles (385 kilometers).

200=193 | 385=386 I know, petty..

I think you meant 200/193 vs 385/386...
I know, I know... petty..:-)

Oct 22, 2017
What I find most amusing is that republican . . . did a good job. This is typical . . . whiners can't do THEIR job. And hope to cover it up by whining.

Getting extra science is bonus. Whining about it is bogus. Get over it, @Fart_A.


I'm right of Genghis Khan, I'm all about mission extensions.

Oct 25, 2017
@ Da Schneib
What I find most amusing is that republicant libertardian whiners complain when someone manages to extend a mission because they did a good job. This is typical republicant libertardian whiner juice. And it's bitter.

Sounds like the republicant libertardian whiners can't do THEIR job. And hope to cover it up by whining.

Getting extra science is bonus. Whining about it is bogus. Get over it, @Fart_A.


Did it ever occur to you that people being wrong does not make them defective? Science is all about trial and error. Those unwilling to err will never venture a testable hypothesis. Name-calling and mocking someone for a wrong-headed idea is the hallmark of religion, not science. Please take it elsewhere.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more