by Ann » Sat Mar 20, 2021 6:46 am
I really, really like this APOD!
![😀](//cdn.jsdelivr.net/gh/twitter/twemoji@latest/assets/svg/1f600.svg)
Because it does a great job of capturing the distinguishing features of the three galaxies in the Leo Trio, M65, M66 and NGC 3628, in a single image!
In the Hubble closeup of M66 at left, you can see that M66 contains a good number of young blue star clusters and also red emission nebulas where new stars are being born. M66 is both
red and
blue.
But where are the young blue stars in M65? Well, take a look at the picture at right. The arrow points at supernova 2013am, which, fascinatingly, was a type II supernova, a massive star undergoing core collapse. But M65 looks all smooth and reddish, doesn't it? Surely there can't be many massive young blue stars in that galaxy?
Well, look again. Can you see a faint bluish patch to the upper left of the supernova? That's a young bluish star cluster. And there are some even fainter star clusters to the left of the brightest blue patch.
My point is that there
are some young stars in M65, but they are very few indeed. And one of them exploded as a supernova that we could see in 2013. But overall, M65 is a
red galaxy.
M65 (top) and M66. Photo: Joseph M. Drudis.
And you must also look at a great picture of M65 and M66 by Jospeh M Drudis, which shows the "puffiness" of M66 compared with M65, and a fantastic portrait of the tail of NGC 3628 by Mark Hanson. Go to
this site and see how Mark Hanson highlights possible dwarf galaxies that may have formed in the tail.
To summarize, and to return to today's APOD:
In a single image, Francis Bozon captured the "red and blue puffiness" of M66, the undisturbed red ellipsoid of M65, and the puffed-up disk ends and tail of NGC 3628.
That's most certainly not bad!
Ann
[float=left][img3="The Leo Trio. M66 is at upper left, M65 is at lower left, and NGC 3628 is at right. Photo: Francis Bozon."]https://apod.nasa.gov/apod/image/2103/TrioduLionLRVB_FrancisBozon1024.jpg[/img3][/float]
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I really, really like this APOD! 😀 Because it does a great job of capturing the distinguishing features of the three galaxies in the Leo Trio, M65, M66 and NGC 3628, in a single image!
[float=left][img3="M66. Credits: NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration; Acknowledgment: Davide De Martin and Robert Gendler"]https://www.nasa.gov/sites/default/files/styles/full_width/public/thumbnails/image/heic1006a.jpg?itok=WqX6hQ3Y[/img3][/float][float=right][img3="M65 with supernova SN 2013am. Photo: Bill Williams."]https://www.inforum.com/incoming/6699834-693o2s-M65-reddened-Bill-Williams-MarchMarch-31/alternates/BASE_LANDSCAPE/M65%20reddened%20Bill%20Williams%20MarchMarch%2031[/img3][/float]
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In the Hubble closeup of M66 at left, you can see that M66 contains a good number of young blue star clusters and also red emission nebulas where new stars are being born. M66 is both [b][size=120][color=#FF0000]red[/color][/size][/b] and [b][size=120][color=#0040FF]blue[/color][/size][/b].
But where are the young blue stars in M65? Well, take a look at the picture at right. The arrow points at supernova 2013am, which, fascinatingly, was a type II supernova, a massive star undergoing core collapse. But M65 looks all smooth and reddish, doesn't it? Surely there can't be many massive young blue stars in that galaxy?
Well, look again. Can you see a faint bluish patch to the upper left of the supernova? That's a young bluish star cluster. And there are some even fainter star clusters to the left of the brightest blue patch.
My point is that there [b][i]are[/i][/b] some young stars in M65, but they are very few indeed. And one of them exploded as a supernova that we could see in 2013. But overall, M65 is a [b][size=120][color=#FF0000]red[/color][/size][/b] galaxy.
[float=left][attachment=0]M65 and M66 Joseph M Drudis.png[/attachment][c][size=80][color=#0040FF]M65 (top) and M66. Photo: Joseph M. Drudis.[/color][/size][/c][/float] [float=right][img3="The amazing tail of NGC 3628. Photo: Mark Hanson."]https://images.squarespace-cdn.com/content/v1/57e97e6ab8a79be1e7ae0ae6/1564407853006-ZVJWZ0TC1HCJB92D3PEE/ke17ZwdGBToddI8pDm48kGeB33QcLXX4B0YrbPbgevx7gQa3H78H3Y0txjaiv_0fDoOvxcdMmMKkDsyUqMSsMWxHk725yiiHCCLfrh8O1z5QPOohDIaIeljMHgDF5CVlOqpeNLcJ80NK65_fV7S1UXZrjS5k81faPYG64x1t-zFuRaAT9Tkcp58k-_urlpaW3U2NFdRjT2Wu9X80bZiijg/NGC3628Finalsmall.jpg?format=1500w[/img3][/float]
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And you must also look at a great picture of M65 and M66 by Jospeh M Drudis, which shows the "puffiness" of M66 compared with M65, and a fantastic portrait of the tail of NGC 3628 by Mark Hanson. Go to [url=https://www.hansonastronomy.com/ngc-3628-mosaic]this site[/url] and see how Mark Hanson highlights possible dwarf galaxies that may have formed in the tail.
To summarize, and to return to today's APOD:
In a single image, Francis Bozon captured the "red and blue puffiness" of M66, the undisturbed red ellipsoid of M65, and the puffed-up disk ends and tail of NGC 3628.
That's most certainly not bad! :D
Ann