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Background
Dawn Dictionary
Dawn Journal
Dawn's Early Light
Fact Sheet (PDF 525 Kb)
FAQs
Ion Propulsion
Mission Status
Objectives
Overview
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Spacecraft
Timeline
Trajectory
Where is Dawn?

Frequently asked questions:

Question: How did the Dawn Mission get its name?
Answer: The mission was not named after a person, but rather it was so named to present a simple image of the purpose of the mission: to provide information on the dawn of the solar system.

Questions by Category
More frequently asked questions about the Dawn mission are grouped below by category. Please select a question to find out the answer. (Tip: To temporarily allow a site to display pop-ups, click the Information Bar when it notifies you that a pop-up has been blocked. Then, click Temporarily Allow Pop-ups.)

MissionCMISSION
Question M1: What is the reason for going to Vesta before Ceres?
Question M2: Will there be opportunities to visit other asteroids, either en route to Ceres or as part of an extended mission?
Question M3: Why does it take so long to get to Vesta and then from Vesta to Ceres? The travel time scheduled appears to be significantly longer than would be required by a Hohmann transfer orbit.
Question M4: I see that a gravitational trajectory assist is scheduled for February 2009 (angular momentum transfer) with Mars. Normally, outward-bound probes pass by the planet while closer to the sun than the planet. The Dawn probe seems to be further away from the sun than Mars, so it would be traveling faster than Mars before the transfer. Wouldn't that slow the probe down, instead of speeding it up with respect to the sun? A more succinct question would be: How much delta V are you expecting from the Mars encounter (heliocentric velocity).
Question M5: Have any of the solar panels been damaged by Micrometeorites during the mission so far?
Question M6: Since the DAWN mission is to fly *through* the asteroid belt, is there any concern it will be hit and destroyed by micrometeorites?

IIon PropulsionCON PROPULSION
Question IP1: In the broadest sense, how does ion propulsion work?
Question IP2: Why did the engineers choose Xenon to propel Dawn's ion engines?
Question IP 3: What makes ion propulsion advantageous for the Dawn mission?
+ See additional NASA FAQs about Ion Propulsion

Answers provided by Chris Russell - Dawn Principal Investigator, Lucy McFadden - E/PO Director, Joe Wise - E/PO Manager, and Marc Rayman - Dawn Project System Engineer.

Site Manager: Dawn Mission Outreach Office
Webmaster: McREL
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