Algol vs Polaris
| Property | Algol | Polaris |
|---|---|---|
| Designation | 26Bet Per | 1Alp UMi |
| Constellation | Perseus | N/A |
| Spectral Class | Class B — B-type (Blue-White) | Class F — F-type (Yellow-White) |
| Apparent Magnitude | +2.09 | +1.97 |
| Absolute Magnitude | -0.11 | -3.64 |
| Distance | 89.9 ly | 433 ly |
| Mass | N/A | N/A |
| Radius | N/A | N/A |
| Temperature | N/A | N/A |
| Luminosity | N/A | N/A |
Key Differences
- ◆ Both are variable stars, but of different physical types.
- ◆ Polaris is a Cepheid variable that pulsates in radius; Algol dims because a companion eclipses it.
- ◆ Polaris's pulsation amplitude has been decreasing over the past century.
- ◆ Algol varies every 2.87 days (eclipsing); Polaris has a period of about 3.97 days (pulsation).
- ◆ Polaris is near the north celestial pole and vital for navigation; Algol is in Perseus and known as the Demon Star.