wookie
05-20-2007, 10:20 AM
Astronomy Picture of the Day
Discover the cosmos! (http://antwrp.gsfc.nasa.gov/apod/archivepix.html) Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2007 May 20
http://antwrp.gsfc.nasa.gov/apod/image/0705/spherule_apollo11_big.jpg (http://antwrp.gsfc.nasa.gov/apod/image/0705/spherule_apollo11.jpg)
A Spherule from the Earth's Moon
Credit: Timothy Culler (UCB (http://eps.berkeley.edu/)) et al., Apollo 11 Crew (http://www.hq.nasa.gov/office/pao/History/alsj/a11/a11.crew.html), NASA (http://www.nasa.gov/) Explanation: How did this spherule come to be on the Moon? When a meteorite (http://www.nineplanets.org/meteorites.html) strikes the Moon (http://antwrp.gsfc.nasa.gov/apod/moon.html), the energy of the impact (http://science.nasa.gov/headlines/y2001/ast30nov_1.htm) melts some of the splattering rock (http://www.teachersource.com/micrometeorites.htm), a fraction of which might cool into tiny glass beads (http://antwrp.gsfc.nasa.gov/apod/ap010523.html). Many of these glass beads (http://www.geocities.com/ladysveva/BeadHistory.html) were present in lunar soil samples (http://www.lpi.usra.edu/expmoon/Apollo17/A17_sampact.html) returned to Earth by the Apollo missions (http://www.nasm.si.edu/collections/imagery/apollo/apollo.htm). Pictured above (http://www.lbl.gov/Science-Articles/Archive/lunar-spherule.html) is one such glass spherule (http://www.thefreedictionary.com/spherule) that measures only a quarter of a millimeter (http://lamar.colostate.edu/%7Ehillger/everyday.htm) across. This spherule (http://antwrp.gsfc.nasa.gov/apod/ap040210.html) is particularly interesting because it has been victim to an even smaller impact. A miniature crater (http://antwrp.gsfc.nasa.gov/apod/ap990711.html) is visible on the upper left, surrounded by a fragmented area caused by the shockwaves (http://antwrp.gsfc.nasa.gov/apod/ap010623.html) of the small impact. By dating (http://www.gpc.edu/%7Epgore/geology/geo102/radio.htm) many of these impacts (http://www.sciencenews.org/20000311/fob3.asp), astronomers can estimate (http://www.lbl.gov/Science-Articles/Archive/lunar-spherule.html) the history of cratering (http://antwrp.gsfc.nasa.gov/apod/ap010428.html) on our Moon.
Tomorrow's picture: shiny dust (http://antwrp.gsfc.nasa.gov/apod/ap070521.html)
< (http://antwrp.gsfc.nasa.gov/apod/ap070519.html) | Archive (http://antwrp.gsfc.nasa.gov/apod/archivepix.html) | Index (http://antwrp.gsfc.nasa.gov/apod/lib/aptree.html) | Search (http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search) | Calendar (http://antwrp.gsfc.nasa.gov/apod/calendar/allyears.html) | Glossary (http://antwrp.gsfc.nasa.gov/apod/lib/glossary.html) | Education (http://antwrp.gsfc.nasa.gov/apod/lib/edlinks.html) | About APOD (http://antwrp.gsfc.nasa.gov/apod/lib/about_apod.html) | Discuss (http://bb.nightskylive.net/asterisk/viewforum.php?f=9) | > (http://antwrp.gsfc.nasa.gov/apod/ap070521.html) Authors & editors: Robert Nemiroff (http://antwrp.gsfc.nasa.gov/htmltest/rjn.html) (MTU (http://www.phy.mtu.edu/)) & Jerry Bonnell (http://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html) (USRA (http://www.usra.edu/))
NASA Official: Phillip Newman Specific rights apply (http://antwrp.gsfc.nasa.gov/apod/lib/about_apod.html#srapply).
NASA Web Privacy Policy and Important Notices (http://www.nasa.gov/about/highlights/HP_Privacy.html)
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& Michigan Tech. U. (http://www.mtu.edu/)
Discover the cosmos! (http://antwrp.gsfc.nasa.gov/apod/archivepix.html) Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2007 May 20
http://antwrp.gsfc.nasa.gov/apod/image/0705/spherule_apollo11_big.jpg (http://antwrp.gsfc.nasa.gov/apod/image/0705/spherule_apollo11.jpg)
A Spherule from the Earth's Moon
Credit: Timothy Culler (UCB (http://eps.berkeley.edu/)) et al., Apollo 11 Crew (http://www.hq.nasa.gov/office/pao/History/alsj/a11/a11.crew.html), NASA (http://www.nasa.gov/) Explanation: How did this spherule come to be on the Moon? When a meteorite (http://www.nineplanets.org/meteorites.html) strikes the Moon (http://antwrp.gsfc.nasa.gov/apod/moon.html), the energy of the impact (http://science.nasa.gov/headlines/y2001/ast30nov_1.htm) melts some of the splattering rock (http://www.teachersource.com/micrometeorites.htm), a fraction of which might cool into tiny glass beads (http://antwrp.gsfc.nasa.gov/apod/ap010523.html). Many of these glass beads (http://www.geocities.com/ladysveva/BeadHistory.html) were present in lunar soil samples (http://www.lpi.usra.edu/expmoon/Apollo17/A17_sampact.html) returned to Earth by the Apollo missions (http://www.nasm.si.edu/collections/imagery/apollo/apollo.htm). Pictured above (http://www.lbl.gov/Science-Articles/Archive/lunar-spherule.html) is one such glass spherule (http://www.thefreedictionary.com/spherule) that measures only a quarter of a millimeter (http://lamar.colostate.edu/%7Ehillger/everyday.htm) across. This spherule (http://antwrp.gsfc.nasa.gov/apod/ap040210.html) is particularly interesting because it has been victim to an even smaller impact. A miniature crater (http://antwrp.gsfc.nasa.gov/apod/ap990711.html) is visible on the upper left, surrounded by a fragmented area caused by the shockwaves (http://antwrp.gsfc.nasa.gov/apod/ap010623.html) of the small impact. By dating (http://www.gpc.edu/%7Epgore/geology/geo102/radio.htm) many of these impacts (http://www.sciencenews.org/20000311/fob3.asp), astronomers can estimate (http://www.lbl.gov/Science-Articles/Archive/lunar-spherule.html) the history of cratering (http://antwrp.gsfc.nasa.gov/apod/ap010428.html) on our Moon.
Tomorrow's picture: shiny dust (http://antwrp.gsfc.nasa.gov/apod/ap070521.html)
< (http://antwrp.gsfc.nasa.gov/apod/ap070519.html) | Archive (http://antwrp.gsfc.nasa.gov/apod/archivepix.html) | Index (http://antwrp.gsfc.nasa.gov/apod/lib/aptree.html) | Search (http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search) | Calendar (http://antwrp.gsfc.nasa.gov/apod/calendar/allyears.html) | Glossary (http://antwrp.gsfc.nasa.gov/apod/lib/glossary.html) | Education (http://antwrp.gsfc.nasa.gov/apod/lib/edlinks.html) | About APOD (http://antwrp.gsfc.nasa.gov/apod/lib/about_apod.html) | Discuss (http://bb.nightskylive.net/asterisk/viewforum.php?f=9) | > (http://antwrp.gsfc.nasa.gov/apod/ap070521.html) Authors & editors: Robert Nemiroff (http://antwrp.gsfc.nasa.gov/htmltest/rjn.html) (MTU (http://www.phy.mtu.edu/)) & Jerry Bonnell (http://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html) (USRA (http://www.usra.edu/))
NASA Official: Phillip Newman Specific rights apply (http://antwrp.gsfc.nasa.gov/apod/lib/about_apod.html#srapply).
NASA Web Privacy Policy and Important Notices (http://www.nasa.gov/about/highlights/HP_Privacy.html)
A service of: ASD (http://astrophysics.gsfc.nasa.gov/) at NASA (http://www.nasa.gov/) / GSFC (http://www.nasa.gov/centers/goddard/)
& Michigan Tech. U. (http://www.mtu.edu/)