Menu

Adhafera — Star in Leo

HIP 50335; Zeta Leonis; 36 Leonis

Magnitude 3.4m Star Leo Visible
Star Map
+ List + Plan

About Adhafera

Description

Adhafera, Zeta Leonis, is an F-type giant of spectral class F0 IIIa about 274 light-years away. It marks the top of the Sickle of Leo — the distinctive backward-question-mark asterism formed by the Lion's head and mane. Adhafera shines at magnitude 3.44, has a mass of about 3 Suns, and is slightly variable due to mild surface pulsations. A faint optical companion is visible at 5.6 arcminutes — far too distant to be physically associated.

Observing Tips

Adhafera forms the topmost point of the Sickle, with Algieba just below it. Binoculars reveal the distant optical companion (magnitude 6) as a wide, unrelated pair. Adhafera is a relatively modest white-yellow point compared to the brighter Regulus anchoring the base of the Sickle. Best observed February through May.

History

The name comes from the Arabic "al-ḍafīrah" meaning "the braid" or "tuft of hair" — a reference to the lion's mane. The IAU formally adopted the name in 2016.

Fun Facts

Adhafera sits at a galactic latitude of 51 degrees, far above the Milky Way plane. Combined with its relatively young age (about 600 million years), this makes it a useful calibration star for surveys of intermediate-age disk stars in this rarely sampled region of the sky.

Observe

1Physical Properties

Magnitude 3.44
Range 3.43 - 3.44
Period 6.4 hours
Variable Type DSCT:+GDOR:
Spectral Type F0IIIa bright giant
Star Color Yellow-white (B-V 0.31)
Distance 274 ly

2Position & Identifiers

RA 10h 16m 41.4s
Dec +23° 25' 02.0"
Constellation Leo
HR 4031
HIP 50335
HD 89025
SAO 81265
Bayer Zeta
Flamsteed 36 Leo

3How easy to spot?

Sign in and configure your equipment and default location to see a personalized row.
Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Easy Easy Medium+
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

Set a location in User Settings to see visibility data.

Best season Jan – Mar (peak: Feb)

5Survey Image

Loading survey image…

Explore

7

Size Comparison

Querying VizieR for stellar data…
8

Compare Stars

9

Spectral Classification

10

Hertzsprung-Russell Diagram

Loading HR diagram…
11

Stellar Lifecycle

12

Blackbody Spectrum

13

Stellar Absorption Spectrum

Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.

14

Stellar Fusion

Discover

15Stellar Notes

Primary unresolved by speckle interferometry 1982.17.
Sirius group; UMa stream.
Adhafera; Aldhafara; Aldhafera.
16

Light Travel Time Machine

17

Relativistic Travel

Nearby in the Sky

Other targets within a few degrees — pan your scope a little and keep exploring.

Visibility scores assume a 150 mm Newton at Bortle 4.

}