Baton Rouge Astronomical Society Forum

It is currently September 21st, 2017, 5:28 am

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 17 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Dawn Mission
PostPosted: July 16th, 2011, 5:50 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
The Dawn spacecraft is entering into orbit around the asteroid Vesta in a few hours--at approximately midnight CDT 17 July. Vesta and Ceres (Dawn's next target) are expected to reveal two aspects of the early solar system--resurfacing and primitive surfaces, respectively.

Ceres was discovered in January 1801 by Guiseppe Piazzi. Vesta was discovered in March 1807 by Heinrich Olbers; it is the third-largest, second most massive, and brightest asteroid.

During the Mars gravity assist of February 2009, Dawn took a calibration image that covered 55 kilometers of Tempe Terra.

Dawn used ion propulsion to reach the needed velocity. Ion propulsion accelerated Dawn to ten times the velocity that could have been accomplished using just a chemical rocket.

More information:
http://www.nasa.gov/mission_pages/dawn/news/dawn20110714.html


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: August 4th, 2011, 11:54 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
Dawn has some spectacular images of Vesta already. Monday it sent back a shot of a series of craters collectively nicknamed "Snowman", for reasons obvious to anyone whose seen it. Dawn was over 5000 kilometers away when it acquired the shot.

In the "General Discussion" section Fred, Trevor, Ben and I have been talking about iron-on transfers of the BRAS logo. The Dawn team has the same idea; its pre-flipped transfer is available in color, and it's fairly sizable.

"Snowman" image:
http://dawn.jpl.nasa.gov/multimedia/dawn_vesta_craters_072411.asp

Iron-on logo:
http://dawn.jpl.nasa.gov/DawnKids/patch_direc.asp


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: August 13th, 2011, 10:12 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
The first science orbit has begun. Called the "survey orbit", it will allow Dawn to map the surface of Vesta in visible and IR wavelengths. Dawn will also be creating mosaics with the framing camera. Survey orbit will be twenty days long; each complete orbit is three Earth days, so that's about seven times around Vesta for surveying.

More information at :
http://www.nasa.gov/mission_pages/dawn/news/dawn20110811.html


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: October 18th, 2011, 8:48 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
The Dawn team went to the Geological Society of America meeting last Wednesday to talk about the mission. Most of the information presented, I think, was about the southern hemisphere of Vesta.

More information:
http://www.nasa.gov/mission_pages/dawn/news/dawn20111012.html


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: December 17th, 2011, 9:36 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
Current data obtained with Dawn back up the idea that HED meteorites are probably from Vesta! Some howardites (the "H" in HED) contain noble gases, suggesting they were part of the surface of whatever object gave birth to them.

The Dawn "Image of the Day" will not be updated until the second week in January.

More information:
http://dawn.jpl.nasa.gov/multimedia/imageoftheday/image.asp?date=20111203


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: March 1st, 2012, 11:56 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
Could Vesta have ice? Few if any of its craters are in permanent shadow, but polar regions may have ice for lengthy periods beneath the surface. The asteroid's tilt is even more pronounced than the Earth's (~27 degrees). The average polar temperatures are less than 150K.

More information:
http://www.nasa.gov/mission_pages/dawn/news/dawn20120125.html


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: May 13th, 2012, 11:15 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
It's certain there are now some happy researchers. Data from the Dawn mission has confirmed that meteorites originating from the asteroid Vesta did indeed make it to Earth! I don't know if protoplanet is the right word, but Vesta has an iron core, mantle and crust. Scientists were also stunned to find the largest impact crater on Vesta is quite young.

An awesome virtual trip has been created by the German Aerospace Center for a short video utilizing data from the Dawn mission. It's fun; I played it three times! The largest of the "snowman" craters is now named Marcia Crater and the flyover of that area is the best of the three scenes.

More information:
http://www.nasa.gov/mission_pages/dawn/news/dawn20120510.html


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: June 26th, 2012, 10:17 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
Well, the end is near...at least, the end of Dawn's data gathering at Vesta. The last session started on June 15. Dawn is no longer a mere 200 kilometers off the surface of the asteroid, as it's been steadily rising in altitude over the past one to two months. After the last major data gathering, it will still be over a month before Dawn is free from Vesta's gravity.

I've received word that there may be another JPL-sponsored celebration, similar to the Vesta Fiesta, celebrating Dawn's striking out toward Ceres. Departure should be in late August, with Dawn finally reaching Ceres in 2015.

More information:
http://www.nasa.gov/mission_pages/dawn/news/dawn20120614.html


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: August 20th, 2012, 11:28 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
Dawn will technically leave orbit around Vesta on Sunday. On the 1st it will look upon Vesta one last time.

With images collected from one low-altitude and two high-altitude orbits, Dawn has given Earthlings a treasure of data over which to pore and delight while Vesta heads toward its next target, Ceres.

More information:
http://dawn.jpl.nasa.gov/mission/journal_07_25_12.asp


Top
 Profile  
 
 Post subject: Re: Dawn Mission
PostPosted: November 8th, 2013, 10:49 pm 
Offline

Joined: October 12th, 2009, 3:28 pm
Posts: 3693
Location: Baton Rouge, LA
Dawn discovered Vesta has a ring of volatile materials around its equator. "Potholes" where the volatiles boiled off can be seen. Dawn did not find water ice at Vesta, but there are signs of hydrated minerals delivered by meteorites. Dawn's gamma ray and neutron detector (GRaND) found signatures of hydrogen.

More information:
http://www.nasa.gov/mission_pages/dawn/news/dawn20120920.html


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 17 posts ]  Go to page 1, 2  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group