Kruger 60 B

Star

Kruger 60 B (DO Cephei) - the fainter red dwarf of the Kruger 60 pair, and a vigorous flare star that can briefly double in brightness. About a sixth of the Sun's mass.

Open in 3D viewSee Kruger 60 B in the live, interactive 3D map

Key facts

Mutual orbit

44.7 Earth years

16,316 Earth days

Mass

3.50 × 10²⁹ kg

0.176 M☉

Radius

166,968 km

24% of the Sun's radius

Surface temperature

2,890 K (2617 °C)

Luminosity

1.30 × 10²⁴ W

Spectral type

M4V (red flare star)

Science

Physical

Mass: 3.50 × 10²⁹ kg · 0.176 M☉
Radius: 166,968 km · 24% of the Sun's radius
Density: 17,953 kg/m³ · 18× water
Spectral type: M4V (red flare star)

Orbit (around the system barycenter)

Semi-major axis: 5.76 AU
Eccentricity: 0.41
Orbital period: 44.67 years

Composition

By mass: A red dwarf about 18% of the Sun's mass that can briefly double in brightness during flares.

Temperature

Surface: 2,890 K (2617 °C)

Radiation & temperature

Luminosity: 1.30 × 10²⁴ W · 0.0034 L☉
Surface temperature: 2,890 K (2617 °C)
Peak wavelength: 1003 nm · near-infrared (mostly invisible to the eye)

Discovery & history

Discovered: January 1, 1890
By: Adalbert Kruger
Name: 'Kruger 60 B' is the fainter component of the binary; its flaring earned the variable-star name DO Cephei.

Its dramatic flares, first noted in the 20th century, earned it the variable-star name DO Cephei.

Images

Where to find it — in Cepheus, the King (IAU constellation chart). To the eye it is a single point of light; no telescope has imaged its surface. — IAU / Sky & Telescope, R. Sinnott & R. Fienberg (CC BY 3.0) · Wikimedia Commons

Images from open archives · credit shown per image