Questions tagged [dawn-mission]

Dawn is a spacecraft that was launched in 2007 to study the Asteroid Belt, specifically Vesta and Ceres.

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Which one of these Isp's for the Dawn spacecraft is wrong?

The Wikipedia article NASA Solar Technology Application Readiness says: The ions are accelerated through two fine grids with roughly a 1300 V difference between them for 2.3 kW operation, with a ...
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Why was Dawn placed into an orbit that would only be stable for “decades”

Last year NASA put Dawn into an orbit around Ceres that Ars Technica said "would remain stable for decades" so as to not contaminate Ceres. Decades are pretty small on the cosmic scale though. Why ...
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Ceres gravity from spherical harmonics from Dawn, how to get the coefficients, definitions and potential?

update: I think I've found what I'm looking for. The file JGDWN_CER18C_SHA.TAB has what looks like spherical harmonics up to order 18, except I don't know the ...
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Is Dawn's upcoming low periapsis orbit for XMO7 “resonant”?

The Spaceflight Insider article Dawn will enter lowest ever orbit around Ceres says: In his Dawn Journal blog, mission director and chief engineer Marc Rayman discussed the challenges of bringing ...
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Xenon vs Hydrazine, “Should I Stay or Should I go?” Dawn mission decisions

edit 2: There seems to have been some announcement/extension by NASA (20-Oct-2017), possibly this will shed more light on the issues in this question. edit 1: Several months have passed since this ...
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How can a yo-yo de-spin maneuver reverse the rotation?

I just read about yo-yo de-spin as a measure to reduce the spin of objects. The basic idea is simple and makes sense, but then I read this: As an example of yo-yo de-spin, on the Dawn Mission […] ...
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If the Dawn probe visits a third asteroid after Ceres and Vesta, which asteroid could it visit?

The Dawn mission was supposed to end after its rendezvous with Ceres, but now, reports say that the Dawn team has asked NASA to extend the mission to visit a third asteroid. There’s only a small ...
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Why do New Horizons and Dawn have such different imagers/cameras aboard?

I asked this in other boards but no one could give me answers. So, can someone tell me: Why can New Horizons (which is older than Dawn) take photos in a way higher resolution than Dawn can (NH: 70m/...
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Why is Dawn in a much higher observation orbit than Rosetta?

Dawn orbits Ceres at thousands of kilometers periapsis altitude, and doesn't seem to plan to go lower than 375 km. In contrast, Rosetta has been down to about 30 km altitude, and will finally even try ...
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Why doesn't Dawn create and release colour images of Ceres?

More than a month has passed since Dawn's arrival to Ceres but we have not seen a single colour image of it in natural colors. Why is this so? Clarification. I am not interested in the details on ...
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Dawn Spacecraft: Why are the orbits so high?

I understand Dawn has a mission to undertake geologic ("Cereologic"?) mapping of Ceres, but its final orbit will be at 22,000 km / 49% disk illumination. Surely, there would be some value for ...
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Why explore Ceres?

The multi-target orbiter Dawn spacecraft, launched in 2007, is now approaching the dwarf planet Ceres and had recently sent high resolution images of Ceres from a distance of 46,000 km. What is so ...
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How does one spacecraft best visit multiple asteroids?

Dawn visits both Vesta and Ceres, thanks to its patient solar electric ion propulsion. AFAIK more xenon and perhaps a little more hydrazine for the attitude thrusters, would've sufficed to give it ...
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Why does the Dawn spacecraft have three ion engines at different angles?

The Dawn spacecraft has three ion engines that are mounted such that their thrust vectors are at significant angles. You can see this in this image: In the image, one of the three engines is active. ...
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How will the ion thruster powered Dawn spacecraft enter orbit around Ceres?

How is it possible for a ion thruster powered spacecraft like Dawn to decelerate to orbit Ceres? Does it have a secondary engine to accomplish this task?
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Dawn - What happens after Ceres? [duplicate]

Soon, the Dawn spacecraft will reach and orbit Ceres. Any ideas about what will happen after this work?
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Does the Dawn spacecraft have the potential for an extended mission?

The Dawn spacecraft is scheduled to arrive in initial orbit around Ceres in February 2015 with a final planned orbital change in December to reduce its orbit to a 700km altitude. At present I can't ...