Sky & Telescope - USA (2020-06)

(Antfer) #1

Pinwheel Perfection


20 JUNE 2020 • SKY & TELESCOPE


Galaxy-Hop Around M101


Object Type Mag(v)

Surface
Brightness Size RA Dec.
M101 Spiral 7.9 14.9 28.8′ × 26.9′ 14 h 03.2m +54° 21′
NGC 5461 H II region 14.0 — 1.1′ × 0.4′ 14 h 03.7m +54° 19′
NGC 5462 H II region 13.5 — 1.5′ × 0.6′ 14 h 03.9m +54° 22′
NGC 5455 H II region 13.0 — 0.5′ × 0.5′ 14 h 03.0m +54° 14′
NGC 5450 H II region 13.0 — 1.0′ × 0.5′ 14 h 02.5m +54° 16′
NGC 5447 H II region 13.5 — 1.0′ × 0.2′ 14 h 02.5m +54° 17′
NGC 5471 H II region 15.5 — 0.3′ × 0.3′ 14 h 04.5m +54° 24′
NGC 5458 H II region 14.0 — 0.5′ × 0.3′ 14 h 03.2m +54° 18′
NGC 5453 H II region 13.8 — 0.3′ × 0.3′ 14 h 02.9m +54° 18′
NGC 5449 H II region 14.0 — 1.0′ × 1.0′ 14 h 02.5m +54° 20′
NGC 5451 H II region 14.0 — 0.4′ × 0.4′ 14 h 02.6m +54° 22′
NGC 5474* Spiral 10.8 14.0 4.7′ × 4.7′ 14 h 05.0m +53° 39′
NGC 5477* Spiral 14.0 14.7 1.7′ × 1.3′ 14 h 05.5m +54° 28′
NGC 5473 Lenticular 11.4 12.8 2.3′ × 1.7′ 14 h 04.7m +54° 54′
NGC 5485 Lenticular 11.4 12.9 2.3′ × 1.9′ 14 h 07.2m +55° 00′
NGC 5486 Spiral 13.2 13.6 1.7′ × 1.0′ 14 h 07.4m +55° 06′
NGC 5484 Elliptical 14.7 13.3 0.5′ × 0.5′ 14 h 06.8m +55° 02′
PGC 50395 Lenticular 13.8 13.0 0.9′ × 0.6′ 14 h 07.7m +54° 48′
NGC 5585* Spiral 10.7 13.9 5.8′ × 3.7′ 14 h 19.8m +56° 44′
NGC 5631 Lenticular 11.5 12.5 1.7′ × 1.7′ 14 h 26.6m +56° 35′
NGC 5678 Spiral 11.3 13.0 3.3′ × 1.6′ 14 h 32.1m +57° 55′
NGC 5422 Lenticular 11.9 12.9 3.9′ × 0.7′ 14 h 00.7m +55° 10′
NGC 5443 Barred spiral 12.3 13.2 2.7′ × 1.0′ 14 h 02.2m +55° 49′
NGC 5475 Spiral 12.6 12.4 2.0′ × 0.5′ 14 h 05.2m +55° 44′
NGC 5204* Spiral 11.3 14.1 5.0′ × 3.0′ 13 h 29.6m +58° 25′
NGC 5109 Spiral 12.9 12.6 1.7′ × 0.5′ 13 h 20.9m +57° 39′
UGC 8837* Barred irregular 13.4 15.1 4.6′ × 1.2′ 13 h 54.7m +53° 54′
NGC 5368 Spiral 13.0 12.3 0.9′ × 0.7′ 13 h 54.5m +54° 20′
NGC 5238 Irregular 13.3 14.1 1.7′ × 1.4′ 13 h 34.7m +51° 37′
NGC 5225 Spiral 13.6 12.7 0.7′ × 0.7′ 13 h 33.3m +51° 29′
NGC 5250 Lenticular 13.0 12.7 1.0′ × 0.9′ 13 h 36.1m +51° 14′
The asterisk denotes M101 Group members. Angular sizes are from recent catalogs. Visually, an object’s size is often smaller than the cataloged value and varies
according to the aperture and magnifi cation of the viewing instrument. Right ascension and declination are for equinox 2000.0.

edge-ons were omitted. The Herschel 400 observing list was
designed for the 6-inch Newtonians that amateurs com-
monly used decades ago, but these days most serious deep-
sky observers opt for bigger instruments. I believe that the
Herschel 400 list should be updated so that it actually offers
the bright and best deep-sky objects beyond the Messiers for
Northern Hemisphere observers.

NGC 5204 , a spiral 3.5° north of Mizar, is a more distant
member of the M101 Group. My 16-inch shows a large oval,
elongated by 3:1. It’s only a very little bit brighter in the mid-
dle, with a very faint nucleus. There are knots or faint stars at
both ends of the long axis. Herschel classifi ed it as Class IV,
which corresponds to his category of “Planetary Nebulae,
Stars with Burs, with Milky Way Chevelure, with Short Rays,
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