AAQ Visual Observing Section

Selected Deep Sky Objects In Lepus

With Orion rising higher in the east summer is a great time of year to explore this area of the night sky. Rich in “faint fuzzies” and many beautiful double stars, I have only just touched on some of them in the highlights below. If you have the opportunity, also spend some time in Eridanus, there are many fine sights within this large meandering constellation.

Unless indicated otherwise all observations were made with a 150mm f8 refractor under dark skies. Comments made in this different text are based on observations under urban night skies using a 14” Schmidt Cassegrain and an 8” Newtonian reflector.

Kappa Leporis (05h 13.2m RA,-12° 57' Dec) With a separation of only 2.3” I found this pair difficult to split with 160x. A clearer separation was apparent with 240x. Yes, it needs good magnification. Clear at 237x in the 14”, but easier with 367x. OK in moments of good seeing at 295x in the 8” (using a 3x Barlow lens).

NGC 1784 (05h 05.5m RA, -11° 52' Dec) & NGC 1832 (05h 12.1m RA, -15° 41' Dec) These two faint galaxies (magnitudes 11.7 & 11.3) were both barely visible with 85x. By using 120x 1832 could be seen using averted vision. It seemed to have a relatively bright centre, but I was unable to tell if this was due to a field star, or the actual core of the galaxy. Both very faint in the 14”. Didn’t bother with the 8”!

PK215-30.1 (05h 03.2m RA, -15° 36' Dec) I was unable to see this magnitude 13 planetary nebula.

BU 314 (04h 59.2m RA, -16° 21' Dec) Not far from PK215 is this pretty double which 40x reveals as a pale yellow primary with a much fainter secondary. Interestingly “The Sky 6” software shows BU314 as only having a separation of .5”. Agreed-very pretty pale yellow and dark blue in the 14” though blue colour less prominent in the 8”. The Cartes du Ciel software indeed shows that the mag. 5.9 primary is a close double (0.8” in 1999 with a mag. 7.5 companion), but also double with the blue mag. 10.4 companion at 53”.

NGC 1730 (04h 59.5m RA, -15° 49' Dec) Another faint magnitude 12.3 galaxy I was unable to find.

R Leporis (04h 59.6m RA, -14° 47' Dec) Commonly known as “Hind’s Crimson Star” this variable star ranges between 5.5 and 11.7 magnitude over a period of about 440 days. At its brighter times a prominent crimson colour is apparently visible, however I did not see a strong colour.

S 476 (05h 19.4m RA, -18° 30' Dec) This was a stunning double, with both components of similar brightness and colour. You will find them easily resolved with 40x. Easy in both scopes ; both white.

NGC 2017 (05h 39.4m RA, -17° 50' Dec) Look near Alpha Leporis for this remarkable grouping of 4 stars in an elongated Y shape. With 40x the brightest star in the centre appeared a pale yellow colour. One of the slightly fainter companions looked a very pale crimson colour. A really interesting asterism, with 6 stars altogether, two much fainter than the others. I agree with Graeme’s colours, but the crimson one looked quite strongly so in the 14”. When I looked at the yellow star in the 14” it looked double so I wound up the magnification (the seeing was good), and at 861x I could see two centres and at 1101x it was pretty clear, at about the correct position angle. Interestingly the Washington Double Star catalogue gives a 2002 separation of 0.4” (which I doubt I could see), but Cartes du Ciel gives a 1991 measure of 0.6”, so I think it is the closest double I have ever resolved.

HJ 3759 (05h 26.2m RA, -19° 41' Dec) Not far from S 476 is another beautiful pair with slightly more magnitude difference. 40x is enough to show a fine field of view with the pale yellow primary part of a lovely colour combination. Pale yellow and blue, with the blue colour paler in the 8”. In the same 47x field are three dimmer more widely spaced stars all in a row.

HJ 3750 (05h 20.5m RA, -21° 13' Dec) This bright yellow primary has a very faint secondary that is just visible with 80x. I could split the pair OK, the difficulty was in glimpsing the secondary. Using 237x in the 14” helped separate the fainter mag. 8.5 secondary from the glare of the mag. 4.7 primary at a separation of about 4”. Then it was easy at 137x and also at 190x in the 8”.

M79 (05h 24.5m RA, -24° 33' Dec) I could glimpse this globular with the finderscope, with 120x revealing some granularity. It appeared to have a somewhat elongated shape. Barely visible in the 8” finder, a smudge at 47x, but a bit more substantial at 190x.

HJ 3752 (05h 22.1m RA, -24° 45' Dec) Use a low power eyepiece and you should see this pair in the same FOV as M79. Set in attractive star field with 40x I could see a yellow primary with a fainter pale crimson secondary. Don’t make the same mistake I did thinking this is the double! After checking its details I learned that it is in fact a close pair of only 3.5” separation. Sure enough, when I observed it again with 120x there was a fainter secondary clearly visible. A nice easy test. Easy at 137x in the 14” and also OK in the 8” but delicate.

Gamma Leporis (05h 44.5m RA, -22° 26' Dec) A stunning very wide (97”), very easy pair with 40x. Look for a fine yellow and orange contrasting double set in a pretty field of bright stars. Both components looked pale yellow to me in either telescope.

LAL 194 (05h 40.1m RA, -20° 25' Dec) Look for this between Gamma & Alpha Leporis. This is a very pretty closer and fainter pair than Gamma and is visible with 40x. Set in another attractive field of bright stars I could see a yellow primary accompanied by a fainter blue/green secondary separated by 10.9”. I was a bit confused by the colours. In the 14” the primary looked white (not yellow) with a blue/green companion just as Graeme says. But in the 8” at either 47x or 190x the companion looked pale red!

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