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NASAexplorer uploaded a new video
(2 days ago)
Late last year, astronomers noticed that an asteroid named Scheila had unexpectedly brightened and it was sporting short-lived plumes. Data from NA...
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Late last year, astronomers noticed that an asteroid named Scheila had unexpectedly brightened and it was sporting short-lived plumes. Data from NASA's Swift satellite and Hubble Space Telescope show that these changes likely occurred after Scheila was struck by a much smaller asteroid.
On Dec. 11, 2010, images from the University of Arizona's Catalina Sky Survey, a project of NASA's Near Earth Object Observations Program, revealed the Scheila to be twice as bright as expected and immersed in a faint comet-like glow. Looking through the survey's archived images, astronomers inferred the outburst began between Nov. 11 and Dec. 3.
Three days after the outburst was announced, Swift's Ultraviolet/Optical Telescope (UVOT) captured multiple images and a spectrum of the asteroid. Ultraviolet sunlight breaks up the gas molecules surrounding comets; water, for example, is transformed into hydroxyl (OH) and hydrogen (H). But none of the emissions most commonly identified in comets -- such as hydroxyl or cyanogen (CN) -- show up in the UVOT spectrum. The absence of gas around Scheila led the Swift team to reject scenarios where exposed ice accounted for the activity.
Images show the asteroid was flanked in the north by a bright dust plume and in the south by a fainter one. The dual plumes formed as small dust particles excavated by the impact were pushed away from the asteroid by sunlight. Hubble observed the asteroid's fading dust cloud on Dec. 27, 2010, and Jan. 4, 2011.
The two teams found the observations were best explained by a collision with a small asteroid impacting Scheila's surface at an angle of less than 30 degrees, leaving a crater 1,000 feet across. Laboratory experiments show a more direct strike probably wouldn't have produced two distinct dust plumes. The researchers estimated the crash ejected more than 660,000 tons of dust--equivalent to nearly twice the mass of the Empire State Building.
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This video is public domain and can be downloaded at: http://svs.gsfc.nasa.gov/goto?10747
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NASAexplorer uploaded a new video
(1 week ago)
NPP is a continuation of the existing Earth-observing satellites (EOS) and it builds on the legacy of multi decades of critical data. In this video...
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NPP is a continuation of the existing Earth-observing satellites (EOS) and it builds on the legacy of multi decades of critical data. In this video, NPP Project Scientist, James Gleason (NASA Goddard Space Flight Center), summarizes the primary messages and explains the essentials of the NPP mission.
This video is public domain and can be downloaded at:
http://svs.gsfc.nasa.gov/goto?10742
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.html
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Or find us on Twitter:
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NASAexplorer uploaded a new video
(1 week ago)
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NASAexplorer uploaded a new video
(1 week ago)
Meet Jim Rice, an astrogeologist whose work has taken him to every continent on the globe. Among the many activities he does as part of his work at...
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Meet Jim Rice, an astrogeologist whose work has taken him to every continent on the globe. Among the many activities he does as part of his work at NASA Goddard Space Flight Center, some of Dr. Rice's favorites include participating in Desert R.A.T.S and working with the Mars rovers.
This video is public domain and can be downloaded at:
http://svs.gsfc.nasa.gov/goto?10741
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f...
Or find NASA Goddard Space Flight Center on facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
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NASAexplorer uploaded a new video
(1 week ago)
April 21, 2011 marks the one-year anniversary of the Solar Dynamics Observatory (SDO) First Light press conference, where NASA revealed the first i...
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April 21, 2011 marks the one-year anniversary of the Solar Dynamics Observatory (SDO) First Light press conference, where NASA revealed the first images taken by the spacecraft.
In the last year, the sun has gone from its quietest period in years to the activity marking the beginning of solar cycle 24. SDO has captured every moment with a level of detail never-before possible. The mission has returned unprecedented images of solar flares, eruptions of prominences, and the early stages of coronal mass ejections (CMEs). In this video are some of the most beautiful, interesting, and mesmerizing events seen by SDO during its first year.
In the order they appear in the video the events are:
1. Prominence Eruption from AIA in 304 Angstroms on March 30, 2010
2. Cusp Flow from AIA in 171 Angstroms on February 14, 2011
3. Prominence Eruption from AIA in 304 Angstroms on February 25, 2011
4. Cusp Flow from AIA in 304 Angstroms on February 14, 2011
5. Merging Sunspots from HMI in Continuum on October 24-28, 2010
6. Prominence Eruption and active region from AIA in 304 Angstroms on April 30, 2010
7. Solar activity and plasma loops from AIA in 171 Angstroms on March 4-8, 2011
8. Flowing plasma from AIA in 304 Angstroms on April 19, 2010
9. Active regions from HMI in Magnetogram on March 10, 2011
10. Filament eruption from AIA in 304 Angstroms on December 6, 2010
11. CME start from AIA in 211 Angstroms on March 8, 2011
12. X2 flare from AIA in 304 Angstroms on February 15, 2011
Be sure to vote on your favorite SDO clip here: http://www.nasa.gov/mission_pages/sdo...
Voting goes from April 21 until May 5.
This video is public domain and can be downloaded at: http://svs.gsfc.nasa.gov/goto?10748
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f...
Or find NASA Goddard Space Flight Center on facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
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