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Trio Leo - APOD 030906

Posted: Fri Mar 10, 2006 7:02 pm
by MrDon
Newbie here with zero formal scientific training. I just had enjoyed APOD for years, and like picking up bits and pieces that I can understand and relaying some of the fascinating things about our universe to my children (who for the most part aren't really that enthused - but I try.)

Finally have a question that I'm sure you all can help with....and it's a basic one really.

In this APOD of the three galaxies, what are all the other points of light? Are they all far off galaxies or are they stars in our own galaxy? I can make out some fuzzy ones to conclude they are galaxies - but for the most part - stars or galaxies?

I'm reminded of the Hubble deep field photos which show an amazing array of galaxies and wondered if a picture like this is similar.

Thanks.

Leo Trio ; her name is Sally, but we all call her Cleo . .

Posted: Sat Mar 11, 2006 12:37 am
by kovil
Mr Don,

My guess is that almost all of the dots of light are stars in our galaxy.

The biggest ones are of 2 possibilities;
1, they are stars and have been 'scrubbed' to remove the verticle and horozonal streaks so common in photos, so as not to mess up the picture.
2, they are globular clusters, a galaxy with no dust ring or arms or flatness.
Most likely reason 1 ; in my estimation, based on their color and appearance.

There are several (one for sure) additional galaxies that are very small in apperance in the background. Click on the picture for the large size and use a magnifying device to look closer. Use your "Zen seeing" to get an additional sense of perception.

In almost any sky photo there are galaxies lurking in the background, it is just, was the exposure long enough to capture enough light to register on the film or CCD used.

Like the fabulous nebula photos with enhanced colors representing different molecules present, emitting, re-emitting, absorbing etc.; one does not see it looking like that in a telescope, it takes a long exposure time, which our eyes do not have the genetic programing to do.

I have gotten spoiled by the fantastic photography these days !

Kovil