Media Information

 
 
 
Collection:
NASA Astronomy Picture of the Day Collection
Title:
Spirals On Edge
Explanation:
Spiral galaxies viewed [ http://antwrp.gsfc.…] face-on display a grand design [ http://antwrp.gsfc.…], with graceful spiral arms traced by bright star clusters and glowing stellar nurseries. When seen edge-on, their appearance is very different but no less striking as their central regions bulge and dark cosmic dust lanes appear silhouetted against starlight from flattened galactic disks. This masterful mosaic of digital images [ http://robgendler.a…] shows nine prominent edge-on spirals arranged as follows: top; NGC2683 [ http://robgendler.a…], M104 [ http://robgendler.a…], NGC4565 [ http://robgendler.a…], middle; NGC891 [ http://robgendler.a…], NGC4631 [ http://robgendler.a…], NGC3628 [ http://robgendler.a…], and bottom; NGC5746 [ http://robgendler.a…], NGC5907 [ http://robgendler.a…], and NGC4217 [ http://robgendler.a…]. Perhaps the best known of these is M104 [ http://www.seds.org…] (NGC4594) whose [ http://www.seds.org…] more descriptive moniker is the Sombrero Galaxy [ http://antwrp.gsfc.…]. Notably, the edge-on perspective of these galaxies allows a measurement [ http://www.astr.ua.…] of their galactic rotation [ http://astrosun.tn.…rotcurve.htm ] speed using the Doppler effect [ http://www.ncsa.uiu…]. Plotting rotation speed versus distance [ http://www.astro.qu…rot-vel.html ] from the center determines a galaxy's gravitational mass and historically [ http://nedwww.ipac.…Faber3.html ] led to premier evidence for mysterious Dark Matter [ http://www.sciam.co…0398cosmos/0398rubin .html ].
Credit and Copyright:
Robert Gendler [ mailto:robgendler@wo rldnet.att.net ]
keyword:
galaxies
keyword:
spiral galaxy
keyword:
dust
keyword:
edge-on
facet_where:
M104
facet_where:
Sombrero Galaxy
facet_where:
Goddard Space Flight Center (GSFC)
original url:
UID:
SPD-APOD-ap010510

Spirals On Edge