In this article, we’ll be sharing with you everything you need to know about the constellation of Leo Minor, including how to find it, deep space objects contained within it and how to use it to find other night sky objects more easily.
The Constellation of Leo Minor
Leo Minor is one of seven constellations that Polish astronomer Johannes Hevelius (1611-1687) created. Hevelius introduced this constellation in his posthumously published Firmamentum Sobiescianum.
This constellation represents a small lion resting next to Leo the Lion and ‘Leo Minor’ means ‘the smaller lion’ in Latin. There are no myths associated with this modern constellation.
To help you spot Leo Minor, here’s what SkySafari 6 shows.
Leo Minor has an area of 232 square degrees making it the 64th largest of the 88 recognized constellations. Leo Minor is often recognized by it’s triangular asterism: 46 Leonis Minoris at the bottom left corner, Beta Leonis Minoris at the top corner and 21 Leonis Minoris at the bottom right corner.
In the next section, you’ll discover how to find Leo Minor.
How To Find Leo Minor In The Night Sky
Leo Minor is part of the Ursa Major family of constellations and is visible to observers at latitudes between +90° and -40°.
Northern Hemisphere observers and Southern Hemisphere observers north of 40° south can see it at its highest in evening skies around April. It’s visible in the dark evening sky between January and July.
The constellation of Leo Minor is bordered by the constellations Leo, Lynx and Ursa Major. It shares a corner with the constellation of Cancer.
To find Leo Minor, do a naked-eye search for the asterism known as The Sickle, which is in Leo. Identify Alpha Leonis (Regulus) – the bright star at the bottom of the Sickle – and hop ~24.5° south to 46 Leonis Minoris (Praecipua).
Alternatively, do a naked-eye search for The Big Dipper and The Sickle. Draw an imaginary line ~38° long from Gamma Ursae Majoris (Phecda) to Gamma1 Leonis (Algieba). 46 Leonis Minoris (Praecipua) is ~22° from Phecda and ~16° from Algieba.
A further alternative is to use the bright stars Dubhe and Merak on the right corners of the Big Dipper (Plough). A line pointing down from them, through Psi UMa, and on to Praecipua.
You can estimate the distances measured in these descriptions simply by using your hand at arm’s length.
To find Leo Minor’s exact position for your location on any night, use software such as Stellarium (free) or SkySafari.
Leo Minor’s Brightest Stars
Leo Minor is a small constellation and doesn’t contain any particularly bright stars – the brightest is only magnitude 3.8 – and only a handful brighter than magnitude five.
Each of them is shown in the star chart below and described in detail underneath that.
Beta Leonis Minoris – This double star is the second brightest star in Leo Minor.
The magnitude 4.21 yellow-orange giant primary and magnitude 6.04 subgiant secondary components are just 0.4 arcseconds apart.
The primary is called Beta LMi A and its mass is 5.8 Solar masses, its radius is 7.8 Solar radii and it’s 12% cooler than the Sun. The secondary is Beta LMi B, and its mass is 1.35 Solar masses, its radius is 2.0 Solar radii and it’s 1.1 times hotter than the Sun. Beta Leonis Minoris is 154 light-years away.
10 Leonis Minoris – This magnitude 4.55 yellow-orange giant is the fourth brightest star in Leo Minor. 10 Leonis Minoris is 185 light-years away and has a mass almost exactly the same as the sun. However, its diameter is 10 times larger than the sun and it’s also 15% cooler than our star.
11 Leonis Minoris – This variable double star is 37 light-years away. The magnitude 5.38 yellow subgiant primary and its magnitude 12.50 secondary component are 6.7 arcseconds apart. The main star has very similar dimensions and temperature to our sun.
20 Leonis Minoris – This double star is 49 light-years away. The primary shines at magnitude 5.38 and is a yellow main-sequence star. The companion is beyond most backyard telescopes with its dim magnitude of 16.00. Once again, the main star is very similar to our sun.
21 Leonis Minoris – This magnitude 4.48 white main-sequence star is the third brightest star in Leo Minor. Its mass is 1.8 Solar masses, its diameter is 1.8 Solar diameters and it is 1.4 times hotter than the Sun. 21 Leo Minoris is 92 light-years away from us.
37 Leonis Minoris – This magnitude 4.67 yellow-orange bright-giant is 578 light-years away. Its mass is the same as our sun’s but its diameter is 19.6 times larger than the sun.
46 Leonis Minoris (Praecipua) – We finish with the brightest star of Leo Minor, an orange subgiant shining at magnitude 3.78. It’s 98 light-years away from us and about 50% more massive that the sun. Its diameter is 8.2 Solar diameters and it’s 19% cooler than the Sun. ‘Praecipua’ means ‘chief’ in Latin.
Star Hopping From Leo Minor
Leo Minor is too dim to be a good starting point for beginner star hops.
Objects To See Within Leo Minor
Leo Minor contains no Messier objects but there is one deep sky object suitable for small telescope users.
NGC 3344 – This spiral galaxy has a magnitude of 9.82 and an apparent size of 6.7 x 6.4 arcminutes. It’s 32 million light-years away and is at right ascension 10h 44m 47s and declination 24° 48’ 03”.
Summary
Leo Minor is a small, dim constellation with only a few stars visible to the naked eye. There is one decent deep sky object for small telescope users to find.
Look for it between Leo and The Big Dipper this April.
