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Use the Big Dipper. The two stars forming the bottom of its bowl — Megrez and Phecda — point south (the opposite direction from the "pointer stars" that lead to Polaris); follow that line down and it lands close to Regulus and the Sickle. Leo also simply rises in the east as the Dipper swings high overhead on spring evenings.

Best seen around 9 p.m. in April, visible from roughly February through June in the evening sky. Not circumpolar from 40°N, though it borders Ursa Major and Leo Minor to the north.

Star	RA	Dec	Mag	Spectral type	Distance	Name
Regulus (α Leo)	10h 08.4m	+11° 58.2′	1.36	B8 IVn	~79 ly	Latin diminutive of "king," translating Greek Basiliskos, itself a translation of Babylonian LUGAL.
η Leo	10h 07.3m	+16° 45.6′	3.51	Luminous white supergiant	~1,300 ly	Marks the top of the Sickle — one of the more distant stars visible to the naked eye.
Algieba (γ Leo)	10h 20.0m	+19° 50.4′	2.08 (combined)	K0 III + G7 III	~130 ly	Arabic al-jabhah, "the forehead." A true binary of two orange-gold giants orbiting every 510 years.
Adhafera (ζ Leo)	10h 16.7m	+23° 25.2′	3.43	F-type giant	~274 ly	Arabic, "the curl" or "braid" of the lion's mane.
Rasalas (μ Leo)	9h 52.8m	+26° 00.6′	3.88	K2 III (red giant)	~124 ly	Arabic raʾs al-asad, "the lion's head."
Ras Elased Australis (ε Leo)	9h 45.8m	+23° 46.2′	2.98	G1 II (bright giant)	~247 ly	Arabic, "the southern head of the lion."
Zosma (δ Leo)	11h 14.1m	+20° 31.2′	2.56	A4 V	~58 ly	Usually explained from Greek zōstēr, "the girdle" — the lion's flank.
Chertan (θ Leo)	11h 14.2m	+15° 25.8′	3.32	A2 V	~165 ly	Latin coxa, "the hip."
Denebola (β Leo)	11h 49.1m	+14° 34.2′	2.14	A3 V	~36 ly	Arabic dhanab al-asad, "the tail of the lion." A very mild, fast variable of the Delta Scuti type.

Regulus is a four-star system: the bright, fast-rotating primary and a companion so close it has never been directly imaged — its presence is inferred from the primary's motion — plus a widely separated, fainter pair of orange and red dwarfs easily split with a small telescope. Regulus itself spins once every 15.9 hours, close to 97% of the speed at which it would fly apart, and rotation has flattened it into a visibly oblate shape.

The Nemean Lion, the Babylonian MUL.UR.GU.LA and the royal star LUGAL, and Leo's place among the four royal stars belong to the zodiac sign's page and aren't repeated here. What's new is a tradition built on entirely different foundations.

In Chinese astronomy, most of Leo — together with part of neighboring Lynx — is occupied by Xuanyuan, a large asterism of seventeen stars representing the mythic Yellow Emperor, Huangdi, in his dragon form. Regulus itself carries the Chinese name Xuanyuan. Where the Mesopotamian and Greek traditions saw a lion, Chinese uranography saw an emperor-dragon over the same ground — an unrelated culture arriving independently at the idea that this bright, central patch of sky belonged to a ruler.

The Leo Triplet — M65, M66, and NGC 3628 (the "Hamburger Galaxy," for the dark dust lane splitting it edge-on) — is a group of gravitationally interacting spiral galaxies roughly 35 million light-years away, all three visibly distorted by their mutual pull; M65 and M66 are separated by only about 160,000 light-years, comparable to the distance between the Milky Way and the Large Magellanic Cloud. A separate, unrelated grouping — M95, M96, and M105, the Leo I Group — sits elsewhere in the constellation at roughly 20 million light-years.

Leo gives its name to the Leonids, an annual mid-November shower tied to Comet 55P/Tempel-Tuttle, whose radiant sits near γ Leonis in the Sickle. Most years it's modest, ten or fifteen meteors an hour. Twice it has been historic.

On the night of 12–13 November 1833, observers across North America saw meteors falling by the tens of thousands an hour — contemporary accounts described the sky as if the stars themselves were falling. Denison Olmsted, a Yale professor, solicited eyewitness reports nationwide through newspapers and showed within weeks that every observer's meteors traced back to a single fixed point in Leo — the effect, he correctly argued, of parallel meteoroid paths seen in perspective, not of chance. The episode is widely credited with founding meteor astronomy as a discipline distinct from vague talk of atmospheric weather.

On 17 November 1966, the Earth crossed a denser part of the same debris stream and produced a second storm, briefly exceeding 40 meteors a second — roughly 144,000 an hour — over a burst lasting fifteen to twenty minutes, among the most intense meteor displays ever recorded.

Date	Event
12–13 November 1833	A Leonid meteor storm over North America produces tens of thousands of meteors an hour; Denison Olmsted's investigation establishes the shower's fixed radiant in Leo.
1930	The IAU adopts Delporte's constellation boundaries.
17 November 1966	A second Leonid storm briefly exceeds 40 meteors a second.

• Leo — the zodiac sign; same name, a different 30 degrees of sky.
• Western Zodiac — the precession that pulled the sign loose from the stars.
• Cancer