Star · K1 III
4 UMa
4 UMa is a giant star of spectral type K1 III in the constellation Ursa Major, 247.0 light-years from the Sun. It is orbited by 1 confirmed exoplanet(s).
| Other names | π² UMa · HIP 42527 |
|---|---|
| Constellation | Ursa Major |
| Distance | 247.0 light-years (75.7 pc) |
| Apparent magnitude | magnitude 4.59 |
| Absolute magnitude | magnitude 0.19 |
| Spectral type | K1 III |
| Surface temperature | 4,420 K |
| Luminosity | 115 L☉ |
| Radius | 18.1 R☉ |
| Mass | 1.23 M☉ |
| Age | 4.6 billion years |
| Metallicity [Fe/H] | -0.25 |
| Right ascension (J2000) | 8h 40m 12.8s |
| Declination (J2000) | +64° 19′ 41″ |
| Space velocity (relative to the Sun) | 27.5 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 4.59). Visible from the whole Northern Hemisphere and south to latitude 26° S. North of latitude 26° N it never sets. It stands highest at midnight in January, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1779. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 4.4 million years.
The Sun seen from there
From a planet around 4 UMa, the Sun would look like a star of magnitude 9.23, in the direction where our sky has the constellation Pavo. It would be invisible to the naked eye.
Planets
- 4 UMa b 270-day orbit · 12.6 R⊕
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
- TOI-3785 14.2 light-years
- HIP 41275 14.3 light-years
- HIP 40380 14.9 light-years
- HIP 44112 15.5 light-years
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.