Beautiful work guys! Very high WOW factor! Jason's
"2001" excerpt is very fitting.
Gary
----- Original Message -----
Sent: Saturday, April 23, 2005 11:10
AM
Subject: [APML] OT: A Deep M13
Hi all,
Here's an M13 collaboration, data by Jim Misti,
processed by me.
http://www.robgendlerastropics.com/M13JM.html
Just
a little clarification about the presence of blue stars in many
globulars.
Many of us have erroneously attributed the blue population
stars to "Blue
Stragglers" which have received lots of publicity recently.
Probably the
vast majority of blue stars in globulars are blue horizontal
branch stars
which having exhausted their hydrogen fuel are now
fusing helium to carbon.
The other bland colored or white stars are mostly
RR Lyrae stars which
surprisingly make up a substantial population of many
globulars. The blue
stragglers which are likely the result of either
collisions
in high
density central regions or mass transfer in binary systems
are
considerably
dimmer than the helium burning horizontal branch stars
and are mostly
located
in the central dense core of globulars.
In
summary many of the blue stars we see in CCD images of
globulars are blue
horizontal branch helium burning stars and not
blue stragglers which are
mostly central and less luminoius than the
other populations
mentioned.
I hope that professional astronomers out there will let me
know if I got
some of this wrong.
Rob Gendler
email: robgendler@att.net
Web Site: http://www.robgendlerastropics.com
_______________________________________________
Astro-Photo
mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo