Some very nice data from Martin Pugh's CDK17. These are the tiny little galaxies on the edge of M83: PGC 48132, the "big" one and PGC 724525, the smaller one. I'm still working on M83 itself. The data deserves more than a quickie process
Mike Sidonio also featured these little critters back in 2015:
Yes very cool little buggers huh Rick?..can't wait for your final masterpiece ...glad to see my lill'oll short focal length 12" f3.8 and without a PMEII, AOL, Protrack etc or even PEC can do so well compared to Martins amazing kitted up 17" rig ...would happily trade though
Yes, some really tiny ones as well, though I suppose they might actually be very large
I wanted to find out how big the larger of the 2 small galaxies is compared to our own Milky Way.
I did some quick scaling by printing the picture of M83 & the little galaxies on one page.
I measured 110mm wide for M83 & 10mm wide for the largest of the 2 small galaxies.
Those galaxies are about 600 million light years away.
M83 is 15 million light years away,
therefore it appears 600/15 = 40 times apparently smaller.
Given that M83 is half the size of our Milky Way
lets double it's size to 220mm and also multiply 40 x 10 mm = 400mm.
If we divide 400mm/ 220 mm = 2.
Therefore the larger of the 2 tiny galaxies is twice the size of our Milky Way galaxy
& therefore about the same size as Andromeda.
It's a large galaxy indeed.
Nice to see the supporting cast of M83 getting a solo gig
They must be Jedi galaxies, you know - distant galaxies far, far away....
Thanks, Andy
Quote:
Originally Posted by Retrograde
Wow - these galaxies are usually only just glimpsed alongside M83. Amazing to have detail in them like this!
Ta, Pete.
Quote:
Originally Posted by Camelopardalis
Neat Rick
Interesting to see how they looking in a substantially larger scope...
Need to go at least twice as big next time, Dunk
Quote:
Originally Posted by Peter Ward
Shaping up well. The stellar footprints look to be half the size of the image you linked to. Nice.
Thanks, Peter. The image is drizzled to twice the native image scale.
Quote:
Originally Posted by strongmanmike
Yes very cool little buggers huh Rick?..can't wait for your final masterpiece ...glad to see my lill'oll short focal length 12" f3.8 and without a PMEII, AOL, Protrack etc or even PEC can do so well compared to Martins amazing kitted up 17" rig ...would happily trade though
Thanks, Mike. The 12" acquitted itself well and is definitely more portable!
Quote:
Originally Posted by alpal
I wanted to find out how big the larger of the 2 small galaxies is compared to our own Milky Way.
I did some quick scaling by printing the picture of M83 & the little galaxies on one page.
I measured 110mm wide for M83 & 10mm wide for the largest of the 2 small galaxies.
Those galaxies are about 600 million light years away.
M83 is 15 million light years away,
therefore it appears 600/15 = 40 times apparently smaller.
Given that M83 is half the size of our Milky Way
lets double it's size to 220mm and also multiply 40 x 10 mm = 400mm.
If we divide 400mm/ 220 mm = 2.
Therefore the larger of the 2 tiny galaxies is twice the size of our Milky Way galaxy
& therefore about the same size as Andromeda.
It's a large galaxy indeed.
cheers
Allan
Thanks, Allan. My back of the envelope calculation puts the major axis of PGC 48132 at 229,000 light-years vs a diameter of 100,000 ly for the Milky Way so essentially the same result.
Very very nice Rick. Great colour balance and outstanding processing, as we can witness in each of your astro images. Mike's version is also outstanding, but since you have provided a link and if I was forced to compare, yours is a notch or two higher...
can do so well compared to Martins amazing kitted up 17" rig 
