✦ Leo (Leo)
✦ Leo (Leo)
Subfolder of: Fixed Stars · Constellations
| Field | Value |
|---|---|
| IAU name | Leo |
| IAU abbreviation | Leo |
| Latin genitive (used in Bayer names) | Leonis |
| Zodiacal constellation | Yes |
| Ptolemaic constellation | Yes — one of Ptolemy’s 48 (Almagest VII–VIII) |
Constellations are not the same as the tropical signs: the signs are 30° divisions measured from the March equinox, while constellations are IAU sky regions of unequal size. Precession has moved the constellations roughly one sign-width against the tropical zodiac since antiquity.
Vault stars in Leo
| Star | Designation | λ J2000.0 | λ 2026.0 | V mag |
|---|---|---|---|---|
| Algenubi | ε Leonis | 20°42′ Leo | 21°04′ Leo | 2.98 |
| Adhafera | ζ Leonis | 27°34′ Leo | 27°56′ Leo | 3.41 |
| Al Jabhah | η Leonis | 27°54′ Leo | 28°16′ Leo | 3.41 |
| Regulus | α Leonis | 29°49′ Leo | 0°11′ Virgo | 1.4 |
| Zosma | δ Leonis | 11°19′ Virgo | 11°41′ Virgo | 2.53 |
| Denebola | β Leonis | 21°37′ Virgo | 21°58′ Virgo | 2.13 |
Sources
- IAU, The Constellations (88 official constellations, abbreviations): https://www.iau.org/public/themes/constellations/
- Swiss Ephemeris fixed-star catalogue
sefstars.txt(ICRS/Hipparcos-based positions, proper motions, magnitudes): https://github.com/aloistr/swisseph/blob/master/ephe/sefstars.txt — ecliptic longitudes computed for this vault with Astropy 8.0 (GeocentricMeanEcliptic, mean equinox of J2000.0 and of 2026-01-01) - Ptolemy, Almagest VII–VIII (star catalogue of 48 constellations), trans. G. J. Toomer (1984)