Regulus vs Spica
A 2.87-magnitude difference in absolute output separates them, −3.44 to −0.57. Regulus is the nearer of the two at 79.3 light-years, while Spica lies 250 light-years away, some 3.1 times farther. By spectral type the pair divides into a B-type star in Leo for Regulus and a B-type star in Virgo for Spica. To the unaided eye Spica leads at magnitude +0.98 to +1.36, a gap of 0.38 worth about 1.4 times the light of Regulus.
Property comparison
| Property | Regulus | Spica |
|---|---|---|
| Designation | 32Alp Leo | 67Alp Vir |
| Constellation | Leo | Virgo |
| Spectral Class | Class B — B-type (Blue-White) | Class B — B-type (Blue-White) |
| Apparent Magnitude | +1.36 | +0.98 |
| Absolute Magnitude | -0.57 | -3.44 |
| Distance | 79.3 ly | 250 ly |
| Mass | N/A | N/A |
| Radius | N/A | N/A |
| Temperature | N/A | N/A |
| Luminosity | N/A | N/A |
Full data for each star: Regulus · Spica
Key differences
Key Differences
- ◆ Both are hot B-type stars lying close to or on the ecliptic, frequently occulted by the Moon.
- ◆ Spica is a spectroscopic binary with tidal distortion; Regulus is a fast-spinning quadruple system.
- ◆ Spica is about 250 light-years away; Regulus is closer at about 79 light-years.
- ◆ Spica's temperature (~25,300 K) is roughly twice that of Regulus (~12,460 K).
- ◆ Hipparchus used Spica observations to discover the precession of the equinoxes around 130 BCE.