A few nebulae and a pair of HHs (some sketched)

This observerving report actually covers two nights as I snuck one observation in before the moon rose last week.

NGC1491 1/24/2008 19:30UT; Pickering 6, NELM 5, SQM 20.2

At 175x, a wide, fan-shaped brightening extending WNW of star; brighter to SW but more extended to N. UHC contributes considerably to extent, particularly to S of star. OIII further darkens background, but without improvement to nebula definition.

260x dims nebula considerably, but brings out more of a void or dark lane between star and nebula, and hints of one pointing from the star to the W. (It's rather shocking to me that I could see that notch. Missed the other one pointing S at the N end of the nebula, though.)

110x with UHC shows greatest extent.

Several days later we got another clear night but with much improved transparency, so I spun over to NGC1999 to look for a couple of Herbig-Haros. HH2 popped into veiw fairly quickly.

HH2 1/29/2008 23:10UT; Pickering 6, NELM 6, SQM 20.8

Stellar and quite dim, about 5' due S of NGC1999. 100% in averted and a good 50% in direct.

HH2 was considerably more difficult, but after 20 minutes of wiggling the scope, circling the area with averted vision, and trying several different diagonal orientations I finally had it confirmed.

HH1 1/29/2008 23:30UT; Pickering 6, NELM 6, SQM 20.8

Much more difficult than HH2; perhaps 25% in averted and hard to re-acquire, but I was able to do so several times in each of several orientations.

While the Herbig-Haro catalog describes HH1 and HH2 as mag 13.0 and 12.5 respectively, the Hubble GSC suggests the two host stars are 14.5 and 12.7, which would match my experience more closely. I did a quick field sketch and recorded three additional stars which were quite difficult but not as hard as HH1; the GSC lists one of them at 14.4.

After that it was on to NGC1788, which turned out to warrant a sketch.

NGC1788 1/29/2008 23:50UT; Pickering 6, NELM 6, SQM 20.8

A fan-shaped nebula extending to the NE of a dim star, reaching nearly to a brighter companion star to the WNW, with a dark lane to the SW directly under the dim central star (or stellar knot within nebula?).

Unhelped by either UHC or OIII.

And, lastly, a very interesting Abell. It was very hard to figure out how to sketch the glare from the star, but I settled on sort of a "ray" pattern.

Abell 12 1/30/2008 00:15UT; Pickering 6, NELM 6, SQM 20.8

Unfiltered at 260x the PN is lost in the star's glare. However, if you move the star around the field, just outside the field-stop, an egg-shaped section of the glare remains when the star is to the ESE.

PN easy in averted, and sometimes direct vision with aggressive filtration (OIII). No structure in PN, but it does have somewhat of an egg shape.

-- Jeff.

The 1st two sketches ALMOST look like the same object revolving aroud the same star.

Paul --

Ha! I had the same thought when I was scanning them. (Did I forget to turn the page in the sketchbook?)

Cheers,
-- Jeff.