Date: 9/12/2015 03:56:18
From: mollwollfumble
ID: 811144
Subject: Dawn at Ceres update.

December 7, 2015 -Dawn to Stop Ion-Thrusting Today in Low Altitude Orbit

Dawn is scheduled to conclude ion-thrusting for its spiral descent shortly before noon today. At that time, it will be orbiting about 240 miles (385 kilometers) above Ceres, closer than the International Space Station is to Earth. After it turns to point its main antenna to Earth, navigators will begin to measure its orbital parameters very accurately. During the next two days, they will analyze the orbit carefully and decide on Dec. 9 whether to make an adjustment at the end of the week. (It is likely such a trajectory correction maneuver will be needed.)

See also Dawn november blog

The following image of Ceres spots was released a couple of days ago. “One of the most intriguing features on Ceres, Occator crater, is seen in this oblique view from NASA’s Dawn spacecraft. This crater is 60 miles (90 kilometers) across and 2 miles (4 kilometers) deep, and is home to the brightest areas on Ceres. This image was acquired from an altitude of 915 miles (1,470 kilometers). Dawn took this image on Oct. 18, 2015.” True brightness.

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Date: 9/12/2015 07:16:31
From: Postpocelipse
ID: 811149
Subject: re: Dawn at Ceres update.

Would those spots be glass created in impact?

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Date: 9/12/2015 18:29:08
From: mollwollfumble
ID: 811638
Subject: re: Dawn at Ceres update.

Postpocelipse said:


Would those spots be glass created in impact?

Unlikely. Glass that has been formed naturally is seldom white or clear.

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Date: 9/12/2015 18:30:35
From: Postpocelipse
ID: 811639
Subject: re: Dawn at Ceres update.

mollwollfumble said:


Postpocelipse said:

Would those spots be glass created in impact?

Unlikely. Glass that has been formed naturally is seldom white or clear.

At that distance I wouldn’t have thought it would need to be. Black glass with an irregular surface would reflect a significant amount of light. Just not sure if it would be that much.

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Date: 10/12/2015 20:09:12
From: ChrispenEvan
ID: 812194
Subject: re: Dawn at Ceres update.

http://www.sciencealert.com/astronomers-have-finally-solved-the-mystery-of-those-weird-bright-spots-on-ceres

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Date: 10/12/2015 20:33:29
From: dv
ID: 812196
Subject: re: Dawn at Ceres update.

ChrispenEvan said:


http://www.sciencealert.com/astronomers-have-finally-solved-the-mystery-of-those-weird-bright-spots-on-ceres

Ammonia clays. Damn.

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Date: 10/12/2015 21:10:09
From: Postpocelipse
ID: 812208
Subject: re: Dawn at Ceres update.

dv said:


ChrispenEvan said:

http://www.sciencealert.com/astronomers-have-finally-solved-the-mystery-of-those-weird-bright-spots-on-ceres

Ammonia clays. Damn.

Seems obvious in hindsight…..

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Date: 10/12/2015 21:10:54
From: dv
ID: 812209
Subject: re: Dawn at Ceres update.

Postpocelipse said:


dv said:

ChrispenEvan said:

http://www.sciencealert.com/astronomers-have-finally-solved-the-mystery-of-those-weird-bright-spots-on-ceres

Ammonia clays. Damn.

Seems obvious in hindsight…..

Rofl

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