Lepus and Columba are a pair of small constellations that lie straight south of Orion. Lepus lies immediately south of Orion, and Columba lies south of Lepus. Lepus has been recognized as a hare since ancient times. Columba was invented around 1600. This constellation is known today as “the dove,” but it was originally invented to represent a specific dove, the one that Noah released from the Ark.
One of the most interesting objects in Lepus is a carbon star known as R Leporis. Most stars emit at least some light from all parts of the spectrum, which is why nearly all the stars we see are whitish, with no more than a tint of color. Carbon stars are different. These stars contain sooty carbon compounds in their outer layers. The carbon compounds scatter the blue light that the stars are emitting, while letting the red light pass through. (Earth’s atmosphere scatters light in the same way at sunrise and sunset.) As a result, carbon stars range in color from yellow-orange to ruby red. All carbon stars are variable stars, varying in brightness over a period of several months or more. Carbon stars appear most vividly colored when they are near their minimum brightness.
R Lep is one of the best carbon stars, shining a vivid red when it is near its minimum brightness. Over a period of about 14 months, this star can get as bright as magnitude 5.5 and as dim as magnitude 11.7, but its minimum and maximum brightness seldom reach these extremes. As of January 2025, R Lep is magnitude 11.4, so it will be quite dim for a while.
To find R Lep, imagine a line connecting Arneb (the brightest star in Lepus) to Mu Leporis. This distance is about 5°. Continue the line another 3.5° past Mu Lep to get to R Lep.
Gamma Leporis, in the southeastern part of Lepus, is a fine double star for smaller instruments. This pair consists of a yellow primary and an orangish secondary star separated by about 95 arcseconds, which is wide enough to easily split with a binocular or telescope at low magnification. Binoculars will give a nice tight split, but telescopes may emphasize the colors of the component stars a little more.
Columba does not contain an abundance of good telescopic targets, but it does hold one nice globular cluster, NGC 1851. This cluster lies in the southwestern corner of Columba, about 5.5° southwest of the star Epsilon Columba. NGC 1851 can be a bit tricky to find since it lies a little distance from any bright stars, so use your lowest magnification to locate the cluster. If your sky is dark, you may want to pinpoint the cluster with a binocular before looking for it with a telescope.
Once you’ve found NGC 1851, experiment with higher magnifications to resolve as many stars as possible. This cluster has a very prominent, condensed core of stars which most telescopes will not be able to resolve, but you may be able to resolve some of the stars in the halo of the cluster. Because NGC 1851 lies so far south, try to observe it when it is near the meridian if you live anywhere north of the tropics.
