Star profile

Alterf

Lambda Leonis · Leo

3D likeness based on its real data · class K · ~4,200 K

What is Alterf

Alterf is an orange class-K giant burning 329 light-years away in Leo, marking on the old charts the gaze of the celestial lion. Its Arabic name, «al-tarf», means precisely «the glance» or «the edge of sight», and indicated the point where the feline fixed its eyes on prey. Cooler than the Sun yet far more voluminous, its coppery tint softens a sky otherwise dominated by Leo's triangular geometry and the piercing white of Regulus.

Where it is and when to see it

Alterf lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is February, when it culminates around midnight.

From London it culminates about 61° above the horizon.
From New York it culminates about 72° above the horizon.
From Sydney it culminates about 33° above the horizon.

It can be seen from anywhere north of 67° S.

It ranks no. 16 in brightness among the 80 stars of Leo in our catalogue. To find it, start from Regulus, the brightest: it lies about 14° away (a fist at arm's length covers about 10°).

The light you see today left it about 330 years ago.

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Astronomical data for Alterf

Constellation: Leo
Apparent magnitude: 4.32
Distance: 329.2 light years
Coordinates (J2000): RA 142.930° · Dec 22.968°
Catalogue: HIP 46750 · HD 82308

A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.

Other stars in Leo

Leo has 80 stars in Stelvia's catalogue. Here are a few of them.

See all 80 stars in Leo