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Blood_Splat
08-26-2007, 10:38 AM
http://www.nasa.gov/mission_pages/galex/galex-20070815.html

Lurch1962
08-27-2007, 06:03 PM
The newsies must have thought it was noteworthy here in Canada. CTV News carried a story about it right after the public announcement was issued.

Being an amateur astronomer myself, I find this kind of stuff fascinating.

Most stars born within our Galaxy's disk (in which are found the spiral arms) have a mean random velocity of about 10 km/s with respect to the circular orbital velocity of ~220 km/sec about the Galactic centre. Our sun has been around long enough (~5 billion years) to have acquired a peculiar velocity of 20 km/s, probably after one or more encounters with giant molecular clouds.

But Mira isn't a member of the Galaxy's thin disk population. It belongs either to the thicker disk or the bulge/halo populations. Hence its larger peculiar velocity of 130 km/s, as it travels on a more elongated and tilted orbit.

That's your astronomy lesson for today... http://forums.ubi.com/images/smilies/partyhat.gif

--Lurch--

snafu73
08-27-2007, 07:30 PM
Hi Lurch, fellow (amatuer) astronomer here!

What about this beauty?

http://antwrp.gsfc.nasa.gov/apod/ap070822.html

Click on the link at the bottom for a zoom in.

Lurch1962
08-27-2007, 07:56 PM
I've seen the Tarantula nebula with my own eyes, during four astrophotography trips to Australia between 1987-1996. In fact, I was there to witness peak brightness of SN1987A in the LMC (Supernova 1987A in the Large Magellanic Cloud, for the non-astronomers who've gotten this far. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif)

--Lurch--