by Ann » Mon Aug 29, 2011 4:51 am
This is a great APOD. Interacting galaxies are very fascinating, and the NGC 3190 group - or, Hickson 44 - is a beautiful group.
I have to question the claim that Hickson 44 shows much evidence of enhanced star formation. One of the galaxies in the group does show enhanced star formation, and that is, of course, S-shaped NGC 3187. However, spiral galaxy NGC 3185 at the upper left is relatively poor in recent star formation, even though it has a large intermediate population. You can see in today's APOD that NGC 3185 does not look nearly as blue as NGC 3187.
As for NGC 3190, it has very little star formation. Few spiral galaxies are as poor in hot young stars as NGC 3190. To get an idea of how many - or how few - young stars it has got, take a look at
this page. Great amateur Robert Gendler has processed a Hubble Space Telescope image of NGC 3190. If you look at the largest version of the picture, you will be able to see small clusters and relatively faint associations of blue stars. But all in all, there are very few of them.
But to summarize, this is a great and beautiful APOD! Tomorrow's APOD is supposedly going to be "very cool", but let me say that today's APOD is very cool, too!
Ann
This is a great APOD. Interacting galaxies are very fascinating, and the NGC 3190 group - or, Hickson 44 - is a beautiful group.
I have to question the claim that Hickson 44 shows much evidence of enhanced star formation. One of the galaxies in the group does show enhanced star formation, and that is, of course, S-shaped NGC 3187. However, spiral galaxy NGC 3185 at the upper left is relatively poor in recent star formation, even though it has a large intermediate population. You can see in today's APOD that NGC 3185 does not look nearly as blue as NGC 3187.
As for NGC 3190, it has very little star formation. Few spiral galaxies are as poor in hot young stars as NGC 3190. To get an idea of how many - or how few - young stars it has got, take a look at [url=http://www.robgendlerastropics.com/NGC3190-HST-Gendler.html]this page[/url]. Great amateur Robert Gendler has processed a Hubble Space Telescope image of NGC 3190. If you look at the largest version of the picture, you will be able to see small clusters and relatively faint associations of blue stars. But all in all, there are very few of them.
But to summarize, this is a great and beautiful APOD! Tomorrow's APOD is supposedly going to be "very cool", but let me say that today's APOD is very cool, too! :D
Ann