Leo Minor (the Little Lion) is a small, faint constellation in the northern sky, situated between Leo and Ursa Major. Unlike its larger namesake, it was not recognized as a separate constellation by ancient Greek astronomers. Instead, it was introduced in the 17th century by Johannes Hevelius.
Although Leo Minor contains no particularly bright stars or Messier objects, it is home to several interesting galaxies, an exceptionally stable pulsating white dwarf, and the remarkable astronomical object known as Hanny’s Voorwerp.
Where Is Leo Minor and When Can You See It?
Leo Minor covers approximately 232 square degrees, ranking 64th among the 88 recognized constellations. It lies between Ursa Major to the north and Leo to the south, with Lynx to the west.
The constellation is best observed from the Northern Hemisphere during spring, particularly in March and April. Its stars are relatively faint, so finding it is easier under dark skies away from city lights.
Who Created the Leo Minor Constellation?
Leo Minor was introduced by the Polish astronomer Johannes Hevelius in 1687 and appeared in his posthumously published star atlas, Firmamentum Sobiescianum, in 1690. Hevelius identified a group of faint stars between the Great Bear and the Lion and gave them the name Leo Minor, meaning Little Lion. Because the constellation was created long after the classical Greek and Roman periods, it has no established ancient Greek mythology. Its name reflects its position near Leo rather than a particular legendary character.
Notable Stars in Leo Minor
- Praecipua (46 Leonis Minoris) – The constellation’s brightest star, an orange giant located around 95 light-years away with an apparent magnitude of 3.8. Its name means “the chief,” reflecting its prominence. Interestingly, Leo Minor has no star designated Alpha Leonis Minoris.
- Beta Leonis Minoris – A binary star system approximately 145 light-years away, with a combined magnitude of 4.2. It consists of two evolved yellowish stars orbiting a common center of mass.
- 21 Leonis Minoris – A white, A-type main-sequence star situated about 90 light-years away. With a magnitude of 4.5, it is hotter and more luminous than the Sun.
- RY Leonis Minoris (G117-B15A) – A pulsating white dwarf with an exceptionally stable brightness cycle of approximately 215 seconds. Its regular pulsations make it one of the most stable natural optical clocks known, helping astronomers study white dwarf cooling and evolution.
Deep-Sky Objects in Leo Minor
Hanny’s Voorwerp — An Echo of a Quasar
One of Leo Minor’s most extraordinary objects is Hanny’s Voorwerp, discovered in 2007 by Dutch volunteer Hanny van Arkel while examining galaxy images through the Galaxy Zoo project.
The object is a vast cloud of glowing gas near the spiral galaxy IC 2497, approximately 650 million light-years away. Its greenish appearance in Hubble images comes from strongly ionized oxygen. Astronomers believe the gas was illuminated by intense radiation from a quasar powered by the galaxy’s central supermassive black hole.
The quasar has since faded dramatically, but the distant cloud still records its earlier activity. This makes Hanny’s Voorwerp an example of a quasar ionization echo, allowing astronomers to investigate how rapidly an active galactic nucleus can change.
Hubble observations have also revealed young star clusters in part of the cloud, possibly formed after gas flowing out of IC 2497 compressed the surrounding material.
NGC 3344 — A Face-On Spiral Galaxy
NGC 3344 is a beautiful spiral galaxy approximately 20 million light-years away.
Because it is oriented almost face-on toward Earth, its spiral arms and central bar can be studied particularly clearly. It is a rewarding target for astrophotographers and observers with larger telescopes.
NGC 3432 — The Knitting Needle Galaxy
NGC 3432, nicknamed the Knitting Needle Galaxy, is an edge-on spiral galaxy roughly 40 million light-years away. Its narrow appearance is caused by our viewing angle, while its disturbed structure reflects gravitational interactions with a smaller neighboring galaxy.
Other galaxies in Leo Minor include NGC 3486, NGC 3504, and NGC 2859.
Does Leo Minor Have a Meteor Shower?
The October Leo Minorids are a minor meteor shower associated with the long-period comet C/1739 K1 (Zanotti). They are generally active during the second half of October, with a peak around October 24. Unlike major annual showers, they produce relatively few meteors and are mainly of interest to dedicated meteor observers.
How to Find Leo Minor
To locate Leo Minor, first identify the familiar Sickle of Leo, which resembles a backward question mark, and the stars of the Big Dipper in Ursa Major. Leo Minor occupies the comparatively empty-looking region between them.
Its brightest stars form a loose, inconspicuous pattern rather than an obvious lion-shaped outline. A detailed star chart and reasonably dark skies are helpful for identifying it.