Boxes in the Sky

by Jane Houston Jones


During a couple recent observing sessions in May 2002, I observed some interesting objects through my telescope which all have something in common. But they are all totally differenct classes of objects! It's the shape that they share. These are all boxes in the sky.

NGC4449 (RA/DE 12h 28.2m +44 06') is a magnitude10 irregular galaxy about 8 degrees north of Cor Caroli, the great long-period binary star in Canes Venatici. It is 9.8 million light-years distant. NGC4449 is located between M94 and M106 at RA 12h 28.2m Dec +44 06m. It's called the Rectangle Galaxy, and it is a Magellanic Dwarf and a member of the Canes Venaticorum group of galaxies. It looks like a tiny duplicate of the Large Magellanic Cloud, with a bright core and several HII regions, one of which resembles, to me, the Tarantula Nebula perched on the edge of the LMC. This magellanic cloud, however is visible to northern hemisphere observers! In fact it is one of the Herschel 400, discovered by Sir William in 1788. Through my 17.5-inch f/4.5 reflector at 222x it also reminds me a little of M76, the little dumbell nebula, except it is twice the size.

The next square I observed was The Box Nebula, NGC6309 ( RA/DE: 17h14.1m, -12 55.0') . This was a treat to find when all I was looking for was Pluto. I started at Eta Ophiuchi and hopped to Nu Serpentis, while starhopping to Pluto, and this little nebula just appeared in my eyepiece. It was a real treat to suddenly have a little mag.11.6 planetary in the eyepiece, when I was concentrating on faint stars. Rectangular in shape, with uneven lobes, it is shaped a little like a chubby exclamation point with the northern lob being the larger of the two. Through my f/4.5 17.5-inch reflector I saw a hint of green color. The central star, magnitude 13.0, was visible with averted vision. At the time I was using the RASC 2002 Pluto finder chart which only shows the stars near Pluto's orbit, so I pulled out my Millennium Star Atlas to see what I had bumped into. You, too can see this on Uranometria 2000.0 page 292, page 1347 of Millennium Star Atlas, and 2-297 of NSOG. I was using a 9 Nagler for 222 power at the time, and this magnification was perfect.

Hickson 61 (RA/DE 12h 12/3m +29.2' is also known as the Box. But unlike the first two objects I described, this is a bright and very pretty galaxy cluster. Up in the northwest of Coma Berenices, four mag.12 and 13 galaxies form a distinct rectangle requiring no averted vision or averted imagination at all. It is one of the relatively bright Hickson galaxy clusters. The four galaxies are 61a - mag. 12.2 NGC4169, 61b - mag. 13.0 NGC4173, 61c - mag. 13.2 NGC4175 and 61d - mag.13.3 NGC4174. Hickson 61a is the brightest of the four and is a lenticular galaxy. Hickson 61b and c are edge-on galaxies forming one side of the box, and 61d, NGC4174 makes up one corner pointing towards 61c. In my 17.5-inch reflector using my 9 Nagler, this cluster was bright enough to show to visitors to the eyepiece. Try it, you'll like it!

Jane Houston Jones
observing near 37N 122W