Algol vs Mira
Four magnitudes and more separate the pair overhead, +2.09 for Algol and +6.47 for Mira. Set side by side at equal distance the ranking changes — absolute magnitudes of −0.11 and +1.66 leave Algol roughly 5.1 times the more luminous. Only 89.9 light-years separate the Sun from Algol; Mira sits 3.3 times further out at 299.
Property comparison
| Property | Algol | Mira |
|---|---|---|
| Designation | 26Bet Per | 68Omi Cet |
| Constellation | Perseus | N/A |
| Spectral Class | Class B — B-type (Blue-White) | Class M — M-type (Red) |
| Apparent Magnitude | +2.09 | +6.47 |
| Absolute Magnitude | -0.11 | 1.66 |
| Distance | 89.9 ly | 299 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: Algol · Mira
Key differences
Key Differences
- ◆ Both are famous variable stars but of completely different types.
- ◆ Algol is an eclipsing binary — it dims when its fainter companion passes in front; Mira is a pulsating long-period variable.
- ◆ Algol varies every 2.87 days; Mira has a pulsation period of ~332 days.
- ◆ Mira is a red giant that sheds material, leaving a 13-light-year tail; Algol is a B-type star system.
- ◆ Algol was probably the first eclipsing variable to be recognized by ancient observers.