Today on Crash Course Astronomy, Phil explains comets. Comets are chunks of ice and rock that orbit the Sun. When they get near the Sun the ice turns into gas, forming the long tail, and also releases dust that forms a different tail. We’ve visited comets up close and found them to be lumpy, with vents on the surface that release the gas as ice sublimates. Eons ago, comets (and asteroids) may have brought a lot of water to Earth -- as well as the ingredients for life.
Check out the Crash Course Astronomy solar system poster here: store.dftba.com/products/crash...
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Chapters:
Introduction: Comets 00:00
Comets = Dirty Snowballs 1:19
Comets Have Two Tails 2:52
Short-Term vs Long-Term Comets 4:35
Where do comets come from? 5:06
Comets Up-Close 6:17
What Happens When Comets Hit Earth? 9:15
Review 10:59
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PHOTOS/VIDEOS
Halley's Comet, 1910 en.wikipedia.org/wiki/File:Hal... [credit: New York Times, Wikimedia Commons]
Bayeux Tapestry upload.wikimedia.org/wikipedia... [credit: Wikimedia Commons]
Comet McNaught [credit: Phil Plait]
Comet McNaught + tail en.wikipedia.org/wiki/C/2006_P... [credit: Chris North, Wikimedia Commons]
Comet surface rosetta.jpl.nasa.gov/sites/def... [credit: ESA/Rosetta/NAVCAM]
Fine structure in the comet’s jets blogs.esa.int/rosetta/2015/01/... [credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA]
Comet Halley apod.nasa.gov/apod/image/1001/... [credit: Halley Multicolor Camera Team, Giotto Project, ESA]
Comet McNaught solarsystem.nasa.gov/multimed... [credit: ESO]
Hubble's Last Look at Comet ISON Before Perihelion en.wikipedia.org/wiki/File:Hub...
[credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)]
Hale-Bopp: The Great Comet of 1997 apod.nasa.gov/apod/ap131013.html [credit: Jerry Lodriguss, used with permission]
Sungrazer video svs.gsfc.nasa.gov/cgi-bin/deta... [credit: NASA's Goddard Space Flight Center]
“Large Web” graphic www.nasa.gov/sites/default/fil... [credit: JHUAPL/SwRI/Dan Durda]
Comet Daniel commons.wikimedia.org/wiki/Fil... [credit: Max Wolf, Wikimedia Commons]
Vega 1 Low Res nssdc.gsfc.nasa.gov/planetary/... [credit: Russian Academy of Sciences]
The Nucleus of Comet Halley sci.esa.int/giotto/51183-the-n... [credit: ESA/MPS]
Comet Hartley 2 en.wikipedia.org/wiki/103P/Har... [credit: NASA/JPL-Caltech/UMD]
Comet 67P/Churyumov-Gerasimenko sci.esa.int/rosetta/54472-come... [credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA]
OSIRIS Catches Activity in the Act blogs.esa.int/rosetta/2015/04/... [credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA]
Active Pit www.esa.int/spaceinimages/Imag... [credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA]
Depiction of Philae 's planned touchdown on the comet en.wikipedia.org/wiki/Philae_(... [credit: DLR, CC-BY 3.0, Wikimedia Commons]
Colour Image of a Comet www.esa.int/spaceinimages/Imag... [credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA]
Comet Lovejoy en.wikipedia.org/wiki/C/2011_W... [credit: NASA/Dan Burbank]
NASA’s Stardust www.nasa.gov/images/content/36... [credit: NASA/JPL]
Comet dust www.nasa.gov/images/content/1... [credit: NASA]
Comet Lovejoy www.eso.org/public/usa/images/... [credit: ESO/G. Brammer]
28 июн 2024
