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Like any wary young cub, Leo Minor keeps itself safely hidden in the undergrowth. In this case the celestial undergrowth between big brother Leo, and the great bear Ursa Major. The form of the cub is difficult to distinguish amongst the faint stars of the region. Polish astronomer Johannes Hevelius was the first to see it hiding there, and identify it in his new star atlas Firmamentum Sobiescianum of 1687. The atlas also introduced the new constellations of Canes Venatici, Lacerta, Lynx, Scutum, Sextans and Vulpecula, which have all survived to this day.
To the brightest star in Leo Minor, Hevelius attached the name Praecipua, Latin for chief, or leader. It is the only named star in the constellation. The star has no Bayer designation, and is left with only its Flamsteed number of 46 Leonis Minoris. Praecipua is a K0III orange giant, with a visual magnitude of 3.83, 98 light years away from Earth.
Beta Leonis Minoris is the second brightest star at magnitude 4.2, and the only star in the constellation to possess a Bayer Greek letter designation. It is a G9III yellow/orange giant with a much smaller, sixth magnitude, spectroscopic companion. This makes it a binary system, located about 150 light years away.
There are three stars with confirmed planets found so far in Leo Minor, all beyond naked eye visibility. Star HD 82886 is 366 light years away at magnitude 7.6 with a planet 1.3 times the size of Jupiter. Star Kelt-3 is even farther away at 580 light years and a magnitude of 9.9 with a planet 1.47 times the size of Jupiter.
HD 87883 is at a much more reasonable distance of 58.88 light years, although still beyond visual range at magnitude 7.56. It is a K2V orange main sequence star with a confirmed planet 1.78 times the size of Jupiter. For more information on these and other extrasolar planets, visit NASA's New Worlds Atlas, and The Open Exoplanets Catalogue.
Like big Leo, little Leo has plenty of galaxies. One of the brightest is NGC 3344, a face-on spiral about 50,000 light years across, half the size of our Milky Way. It has a magnitude of 9.9, and is about 25 million light years away.
The spiral galaxy NGC 3021 is much farther away, at a distance of 92 million light years. It is about 44,000 light years across, and has a magnitude 12.1.
Out at the ridiculous distance of 650 million light years is the spiral galaxy IC 2497. A magnitude of 13.8 puts it well into the realm of large telescopes, but it came into world view after the discovery of an extraordinary object right beside the galaxy, spotted in 2007 by sharp-eyed Dutch school teacher Hanny van Arkel doing volunteer work classifying galaxies for the online Galaxy Zoo project. Using the Dutch word for "object", it was christened Hanny's Voorwert, and it turned out to be such a strange and unique discovery, Hanny found herself in the spotlight, enjoying her well deserved 15 minutes of fame.
A composite Hubble image of Hanny's Voorwert shows the stunning grandeur of this truly immense emission nebula, glowing oxygen green, as vast as an entire galaxy. The theory is that it was part of a galaxy pulled away by a black hole at the centre of IC 2497 that formed a quasar which ionized the gases in the nebula and initiated star formation. It was the first object of its kind ever found.
Traveling even farther from home we find the enormous Galaxy Cluster SDSS J1004+4112. Located a mind boggling 7 billion light years away, the combined gravity of all these galaxies is strong enough to bend and magnify the light from objects behind them, a process known as gravitational lensing. In this case the light from a far away quasar, the most powerful known energy source in the Universe, has been captured and manipulated by the intense gravity well of the cluster, producing five distinct images of the distant quasar (circled in the image below).
The NASA diagram below illustrates the process of a gravitational lens. The bright light of the quasar is bent around the edges of the cluster, magnifying it and splitting it into multiple images. The source of the quasar is a black hole at the centre of a galaxy 10 billion light years away, a distance so great it is incomprehensible, and speaks to the equally incomprehensible energy of the quasar to appear so bright from so far away.