Leo V is a dwarf spheroidal galaxy situated in the Leo constellation and discovered in 2007 in the data obtained by the Sloan Digital Sky Survey. ^[2] The galaxy is located at a distance of about 180 kpc from the Sun and moves away from the Sun with the velocity of about 173 km/s. ^[2] It is classified as a dwarf spheroidal galaxy (dSph) meaning that it has an approximately spherical shape with the half-light radius of about 130 pc. ^{[3] [note 1]}

Leo V is one of the smallest and faintest satellites of the Milky Way—its integrated luminosity is about 10,000 times that of the Sun (absolute visible magnitude of about −5.2 ± 0.4), ^{[note 1]} which is much lower than the luminosity of a typical globular cluster. ^[3] However, its mass is about 330 thousand solar masses, which means that Leo's V mass to light ratio is around 75. A relatively high mass to light ratio implies that Leo V is dominated by dark matter. ^[4] The stellar population of Leo V consists mainly of old stars formed more than 12 billion years ago. ^[2] The metallicity of these stars is also very low at [Fe/H] ≈ −2.0 ± 0.2, which means that they contain 100 times less heavy elements than the Sun. ^[4]

The galaxy is located only 3 degrees away from another Milky Way satellite, Leo IV. The latter is also closer to the Sun by 20 kpc. These two galaxies may be physically associated with each other. ^[2] There is evidence that they are connected by a star bridge. ^[3]

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