Object of the Week, March 23, 2025 - the Haro Berenice

[Clear Skies]

Berenice's Hair. Strange name for a constellation.

I mean, there's plenty out there to frown upon. Not the mythological persons and creatures, or constellations named for animals, of course... but there are tools, a mountain, even parts of a ship... But a body part? Coma Berenices, the Hair of Berenice, is truly the only one.

This celestial Rapunzel is filled to the brim with galaxies. Hundreds are within reach of our scopes, along with the large naked eye star cluster Melotte 111 and three nice globulars. More than plenty for nights and nights of stargazing.

Perhaps the best-known of the many galaxies are galaxy groups in this constellation is the Coma Cluster, a.k.a. Abell 1656. A close pack of mostly small but not-too-faint galaxies. It's just south of that cluster where we find our Object of the Week for this week.

Less than half a degree south-southwest of the middle of the galaxy cluster, there's a planetary nebula. It's very small, almost stellar, but relatively bright. Discovered by Guillermo Haro in the year 1951 and as such first mentioned in a Harvard announcement card by Shapley and later by Haro himself. It lives at 12:59:28 +27d38m00s.

DSF OotW 2025-12 - Haro 4-1 Com_1.jpeg DSF OotW 2025-12 - Haro 4-1 Com_2.jpeg DSF OotW 2025-12 - Haro 4-1 Com_3.jpeg DSF OotW 2025-12 - Haro 4-1 Com_4.jpeg DSF OotW 2025-12 - Haro 4-1 Com_5.jpeg

Here's the guide in pdf.

Myself, I have yet to observe this planetary. There is an observation by Steve Gottlieb on Cloudy Nights, proving it is in reach of moderately large amateur scopes.


So there you have it: the Haro Berenice.

[wvreeven]

My observation of the planetary nebula with my 20" dob is in the Abell 1656 page that you already linked:

I located the planetary nebula at 320x and it was visible as a faint star. When I used my OIII filter all other stars disappeared but the planetary nebula remained visible.

[KidOrion]

Or even more colloquially, the Hair o' Berenice.

[Steve Gottlieb]

My two observations were made 39 years ago with an early 13.1" Coulter Odyssey (blue sonotube). The planetary itself was unremarkable (guesstimated at mag 14.5-15.0), but the location 20' S of NGC 4874 in the heart of Abell 1656 made in special!

It was visible unfiltered at 166x to 214x (two powers I often used) as a faint "star" and easy to identify by blinking with a UHC filter (at even 62x).