Star · K8V
GJ 3640
GJ 3640 is a main-sequence star of spectral type K8V in the constellation Ursa Major, 99.4 light-years from the Sun.
| Other names | HIP 54105 |
|---|---|
| Constellation | Ursa Major |
| Distance | 99.4 light-years (30.5 pc) |
| Apparent magnitude | magnitude 10.74 |
| Absolute magnitude | magnitude 8.32 |
| Spectral type | K8V |
| Surface temperature | 3,950 K |
| Luminosity | 0.122 L☉ |
| Radius | 0.746 R☉ |
| Mass | 0.591 M☉ (estimated) |
| Right ascension (J2000) | 11h 04m 15.9s |
| Declination (J2000) | +40° 00′ 17″ |
| Space velocity (relative to the Sun) | 44.0 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 10.74. Visible from the whole Northern Hemisphere and south to latitude 50° S. North of latitude 50° N it never sets. It stands highest at midnight in March, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1927. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.8 million years.
The Sun seen from there
From a planet around GJ 3640, the Sun would look like a star of magnitude 7.25, in the direction where our sky has the constellation Grus. It would be invisible to the naked eye.
Neighbours
Its nearest neighbours in the catalogue (within 20 light-years):
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.