Exploring Bright Galaxy Groups in Leo

Hickson 44 members
Three members of the NGC 3190 group also referred to as Hickson 44 show nice variety in kind. From left: NGC 3193, NGC 3190, and NGC 3187. This group and others prefer it make their residence in Leo. North is up in this and all photographs besides the place famous.
PanSTARRS DR1 / Aladin Sky Atlas

Whenever I watch a TV present or film filmed in pre-COVID occasions I cringe at scenes that includes packed eating places, bars and live performance crowds. What was regular actions now appear so alien. Hopefully, that can change quickly. There’s no denying the correct crowd engenders vitality and pleasure; gathering in teams to satisfy and share concepts is the essence of being human. I am unable to wait to really feel that vibe once more.

Likewise in the sky. When we come throughout a discipline thick with stars or spilling over with galaxies our thrill-meter goes up. Seeing three, 4, or 5 deep-sky objects in the identical view appears like reaching the summit with a sweeping view of peaks throughout. Grander, actually. With galaxy teams, we’re taking a look at stellar congregations as much as one million or extra light-years throughout, separated by tens of hundreds to thousands and thousands of light-years. What magic frames a lot space in the tidy circle of the eyepiece?

Leo finder map
To discover Leo use the Bowl of the Big Dipper.
Stellarium

We’re going to go to three such teams in Leo, all properly positioned in the southeastern sky round 10 p.m. native time in the latter half of March. The waxing Moon will intrude beginning in regards to the twentieth however will get out the way once more by month’s finish. My observations have been made with a 15-inch reflector underneath Bortle 3 skies, rated as rural/suburban transition.

I intentionally chosen brighter teams (and the brighter galaxies inside these teams in some instances), so all of those also needs to be seen in an 8-inch telescope and some in apertures as small as 6-inches.

When you observe these clumps, image them as distant variations of our personal Local Group. Each group can be a member of both the Leo I or Leo II galactic clouds, bigger assemblages of galaxies at distances of roughly 35 million light-years and 75 million light-years, respectively. Like nested matryoshka dolls these fold into the Virgo Supercluster which is a part of even vaster construction, the Laniakea Supercluster.

NGC 3227 Bunch — Leo II Group

Leo galaxies finder chart
Use this detailed map to navigate to our focused galaxy teams. Stars are proven to magnitude 9. Click for a big model and save.
Stellarium with additions by the writer

One of the best teams to search out, the NGC 3227 bunch is situated ¾° east of 2nd-magnitude Gamma (γ) Leonis, also referred to as Algieba. In a great sky, even a 6-inch scope will present two galaxies in contact — the spiral NGC 3227 and its companion NGC 3226, a dwarf elliptical. Also often known as Arp 94 from astronomer Halton Arp’s Atlas of Peculiar Galaxies, this interacting pair makes for a compelling sight. NGC 3227 is the brighter of the 2 at magnitude 10.3 and clearly elongated northwest-southeast with a distinguished near-stellar nucleus.

Use magnifications north of 200× to understand its blazing depth and to image what lurks right here, a supermassive black hole some 14 million occasions extra large than the Sun — greater than thrice the heft of the Milky Way’s darkish coronary heart.

Interacting galaxies NGC 3226-3227
NGC 3227 and NGC 3226 take staying in contact actually. The interacting pair, also referred to as Arp 94, make a putting sight in 8-inch or bigger telescopes.
SDSS9 / Aladin Sky Atlas

NGC 3227 is a Seyfert galaxy with an energetic, quasar-like nucleus that sparkles in X-rays on time scales of hours to months. Tidal interactions with NGC 3226 to the northwest have spawned blue knots of star formation inside their widespread envelope. NGC 3226 is about half as giant as its companion and slightly fainter at magnitude 11.4. At first look it seems spherical however reveals a faint, outer envelope angled northeast-southwest with averted imaginative and prescient. It additionally possesses a vibrant, nonstellar nucleus.

A 3rd a lot fainter member of the group, NGC 3213 (magnitude 13.5, dimension 1.1′ × 0.9′), sits 33′ off to the southwest of the duo on the fringe of Algieba’s glare zone. Use magnifications of 200× and better to catch this midge. Another unrelated, extra distant galaxy, NGC 3222 (magnitude 12.8, 1.3′ × 1.1′), lies 12′ west of the NGC 3226-27 pair. All 4 match in a 1° discipline with room to spare.

NGC 3190 bunch — Leo I group

If NGC 3226-27 is your first cease you do not have to go far to search out our subsequent batch of furry galactic catkins. The NGC 3190 group seems simply 2° north of Gamma (γ) Leonis on a line to Zeta (ζ) Leonis in a discipline peppered with vibrant telescopic stars starting from magnitude 7.5 to 10.5. This tight clump of 4 galaxies spans simply 17′extensive, which suggests you should utilize magnifications of 200× or extra and maintain all of them in the identical discipline of view.

NGC 3190 group / Hickson 44
Comprising three spiral galaxies and one elliptical, the NGC 3190 group (Hickson 44) is wealthy in selection for the visible observer. The weird NGC 3187 seems at prime with NGC 3193, NGC 3190, and NGC 3185 in a row from left to proper. North is at higher proper.
Stephen Leshin

The galaxy NGC 3193 (magnitude 10.9, 2.0′ × 2.0′) is a traditional elliptical — spherical and fuzzy with a brighter core and near-stellar nucleus. A 9.6-magnitude star pins its northern border. While the spiral NGC 3190 (magnitude 11.1, 4.4′ × 1.5′) seems a tad fainter it was my favourite with an clearly elongated disk and a vibrant, prolonged nuclear area that swaddled a bloated, starlike nucleus. NGC 3185 (magnitude 12, 2.3′ × 1.6′) was a small, faint oval oriented northwest-southeast with a stellar core and barely brighter interior disk.

I’d hoped to see the barred spiral NGC 3187‘s (magnitude 13.4, 3.6′ × 1.6′) wacky spiral arms, flung out on both aspect like a swing dancer, however it is a faint, diffuse object, and the most effective I may do was make out a misty, elongated disk tipped northwest-southeast at 257× with averted imaginative and prescient. Both NGC 3127 and neighboring NGC 3190 exhibited warped disks, proof of tidal interactions widespread amongst galaxies in compact clusters.

NGC 3607 bunch — Leo II group

Located in the tail of Leo this group has two cores, one centered on NGC 3607 and the second on NGC 3684, some 2.7° to the southeast. NGC 3607, a spiral galaxy and the group’s brightest and member at magnitude 9.9 and 4.7′ throughout, varieties a decent trio with NGC 3608 (magnitude 10.8, 3.2′ × 2.6′) and faint NGC 3605 (magnitude 12.3, 1.5′ × 1.0′) in a north-south line. A fourth member, NGC 3626 (magnitude 11.0, 2.7′ × 1.9′), lies 50′ to the northeast.

NGC 3607 "Eyes"
The two “eyes” of NGC 3607 and NGC 3608 dominate the western half of the NGC 3607 group. NGCs 3599 and 3605 aren’t members regardless of appearances.
SDSS9/ Aladin Sky Atlas

NGC 3607 and 3608 resemble a pair of eyes at first look, however NGC 3607 is clearly the brighter with a dense, luminous core and starlike nucleus set in a barely elongated disk oriented northwest-southeast. The elliptical galaxy NGC 3608 is second canine right here — slightly smaller and fainter and prolonged east-west. Although NGC 3605, additionally an elliptical, appears prefer it belongs to the group as a consequence of its proximity to NGC 3607, it is really a lot nearer to us at 33 million light-years, making it a probable member of the Leo I group.

NGC 3626 (magnitude 11.0, 2.7′ × 1.9′), a real member, sits off by its lonesome 48′ northeast of the primary bunch. It’s a vibrant spiral prolonged northwest-southeast with a vibrant, stellar nucleus. While you are poking round you may additionally discover one other faint galaxy sharing the sector with NGC 3607-08, round 20′ to the west. This delicate puff with a brighter core is NGC 3599 (magnitude 12.0, 2.7′ × 2.1′), a spiral galaxy and one other potential member of the Leo I group.

NGC 3607 group
Four galaxies in the form of an airplane (higher left) and NGC 3655 kind a compact subgroup throughout the NGC 3607 group.
PanSTARRS DR1 / Aladin Sky Atlas

Moving east we arrive on the second core, composed of 4 reasonably dim galaxies that comfortably match inside the sector of view of my 142× Nagler eyepiece — three in an evenly-space northeast-southwest line with the faintest member, NGC 3691 (magnitude 11.8, 1.3′ × 1.0′), shut by to the southeast. NGC 3686 (magnitude 11.3, 3.2′ × 2.5′), a barred spiral, is the brightest and largest member of this engaging group.

In good seeing at 257× I may discern a faint, prolonged nuclear area inside a mottled disk elongated northeast-southwest. A 15.5-magnitude star seems contained in the barred galaxy’s southern edge. The extra tightly-wound spiral, NGC 3684 (magnitude 11.4, 3.1′ × 2.1′), shows a brighter core however lacks a stellar nucleus like its neighbor NGC 3681 (magnitude 11.2, 2.0′ × 2.0′) instantly southwest.

NGC 3691 was a dab of faint, uncondensed gentle. Farther afield, 1° west-southwest of the quartet, you will discover one other group member, NGC 3655 (magnitude 11.7, 1.5′ × 1.0′) clearly elongated northeast-southwest with a vibrant, prolonged core dotted with a nonstellar nucleus.

If you are in extra galaxies in the area, akin to the intense M105 group and the Leo Triplet, please try my earlier blog and Howard Banich’s article on web page 18 of the April 2021 situation of Sky & Telescope. One of the challenges in observing these teams is taking the time to differentiate particulars in what appears like simply one other faint fuzzy. That’s why destiny positioned galaxies in the spring and fall skies, when temperatures are conducive to spending extra time on the telescope and the dreaded mosquitos are scarce.

Asteroid information

PHA 2001 FO32 on the move
Italian astronomer Gianluca Masi took this photograph of 2001 FO32 on March 16, 2021. Masi will livestream views of the asteroid on March twenty second beginning at 04:00 UT (midnight EDT, March 21–22).
Gianluca Masi

On March twenty first at 16:03 UT (12:03 p.m. EDT), the possibly hazardous asteroid 2001 FO32 will attain its minimal distance from Earth of about 2 million kilometers. Measuring between 440–680 meters (1,400–2,200 ft) throughout, this huge object will turn out to be as vibrant as magnitude 11.7 on the morning of March twenty first because it speeds throughout southern Sagittarius. Traveling at round 14′ per hour, you might even detect its movement in actual time at magnifications of 200× or extra. The asteroid rapidly fades after the twenty first however may be noticed earlier on March twentieth in Lupus at magnitude 12.0. For maps, go to astro.vanbuitenen.nl. Due to its southerly declination it is best seen from the southern U.S.

Then, on March seventeenth, observers in the southwestern U.S. will witness among the finest asteroidal occultations of 2021 when 10.7-magnitude 8 Flora covers a 7.2-magnitude star close to the Hyades in Taurus. Your observations of the occasion shall be of nice worth in figuring out particulars of Flora’s form and different parameters. The occultation will last as long as 5 seconds with a 1.8-magnitude drop. It would usually be bigger, based on David Dunham, with the International Occultation Timing Association (IOTA), however the star’s 9.06-magnitude companion will stay seen throughout the occultation. You’ll discover finder charts and full particulars here.


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