Star · K4V
GJ 3978
GJ 3978 is a main-sequence star of spectral type K4V in the constellation Hercules, 98.4 light-years from the Sun.
| Other names | HIP 82440 |
|---|---|
| Constellation | Hercules |
| Distance | 98.4 light-years (30.2 pc) |
| Apparent magnitude | magnitude 9.20 |
| Absolute magnitude | magnitude 6.80 |
| Spectral type | K4V |
| Surface temperature | 4,530 K |
| Luminosity | 0.291 L☉ |
| Radius | 0.876 R☉ |
| Mass | 0.735 M☉ (estimated) |
| Right ascension (J2000) | 16h 50m 54.4s |
| Declination (J2000) | +38° 09′ 01″ |
| Space velocity (relative to the Sun) | 22.1 km/s |
In the sky
A telescope is needed to see it: its apparent magnitude is 9.20. Visible from the whole Northern Hemisphere and south to latitude 52° S. North of latitude 52° N it never sets. It stands highest at midnight in June, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1928. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 1.7 million years.
The Sun seen from there
From a planet around GJ 3978, the Sun would look like a star of magnitude 7.23, in the direction where our sky has the constellation Caelum. 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.