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View Full Version : Object of the Week, April 28, 2024 - Core business



Clear Skies
April 28th, 2024, 09:09 AM
This week's OotW is not a large object. It does not reveal a lot of detail. It's not an Arp, a Hickson or a Vorontsov-Vel'yaminov nor is it included in any other "usual suspects" list and - despite it being not too faint - it even managed to avoid the NGC and IC catalogs.

The other night (https://clearskies.eu/astronomy/observing/sessions/sessions2024/10apr2024/) I was stargazing in France (blog coming soon (https://clearskies.eu/blog/astrotrips/10apr24/)) and as part of my observing plan, this little fella made it into my eyepiece. At first glance, there wasn't much to say about it. Just another small, elongated glow, gradually brighter in the middle with a bright nucleus.

Averted vision changed that. What really popped out was the galaxy's core. The transition of this galaxy's outer regions to its core is more abrupt than I can recall to ever have observed. Also, the nucleus that was already clearly visible without use of averted vision, seemed to be positioned just west of the middle.

14" SCT + 17mm Nagler T4 = 168x / 29':


Without AV a slightly east-west elongated glow, gradually brighter in the middle with a bright nucleus that is clearly visible without AV. With AV the galaxy is more elongated and suddenly brighter in a bright, notable core that is elongated in the same direction. The sudden transition to the core is notable. The nucleus is just a bit west of the middle.
The galaxy is in the right angle of right angled triangle with a mag. 11 star to the south in the shorter leg of the triangle and another mag. 11 star 2 1/2 times that distance towards the west in the longer leg of the triangle.


The object is MCG+08-20-033 (PGC32536, UGC5953). It lives at 10:51:18 +44°34'11", that's in the southern regions of Ursa Major. Nearest bright star is Omega Ursae Majoris (https://en.wikipedia.org/wiki/Omega_Ursae_Majoris), shining at mag. 4.7 with an A0 spectrum, a degree and a half to the south-southeast.

Benik Markarian (https://en.wikipedia.org/wiki/Benjamin_Markarian) chalked it up as nr. 155 on his list (https://en.wikipedia.org/wiki/Markarian_galaxies); that implies the nucleus is brighter than usual in UV, but that by itself is of little value to us visually inclined... unless that is contributing to the brightness of the nucleus, as noted above.

Some catalogs list it as peculiar. Hyperleda says it's class S0-a, NED assigns it E/S0.

The POSS images tell us very little, as the brightness of the galaxy washes out any detail. Both images below, POSS2 Blue and Red respectively, are 5' in size:

5426 5427

Thankfully, the SDSS and PanSTARRS images tell us more and do reveal the very suddenly brighter core.

5428 5429

Here's the observing guide (https://clearskies.eu/csog/downloads/dsfootw2024#17):

5430 5431 5432

There isn't much going on in the vicinity. Brightest star within a degree is mag. 8.0 SAO43476, just over 30' to the west-northwest. Double star Espin 2635 (WDS10532+4359 (https://www.stelledoppie.it/index2.php?menu=29&iddoppia=48792)) is a little further to the south-southeast. Nearest bright galaxy is NGC3415 with it north-northeasterly neighbor NGC3416, almost a degree due south and 40 minutes of arc north-northwest of aforementioned Ome UMa.

As far as I can tell, there are no observations of MCG+08-20-033 out there. You can change that.. so give it a go and let us know!