Star · K2 III
HD 240237
HD 240237 is a supergiant star of spectral type K2 III in the constellation Cassiopeia, 3,009 light-years from the Sun. It is orbited by 1 confirmed exoplanet(s).
| Other names | HIP 114840 |
|---|---|
| Constellation | Cassiopeia |
| Distance | 3,009 light-years (922.4 pc) |
| Apparent magnitude | magnitude 8.38 |
| Absolute magnitude | magnitude −1.44 |
| Spectral type | K2 III |
| Surface temperature | 3,930 K |
| Luminosity | 309 L☉ |
| Radius | 71.2 R☉ |
| Mass | 8.76 M☉ |
| Age | 4.4 billion years |
| Metallicity [Fe/H] | -0.25 |
| Right ascension (J2000) | 23h 15m 42.2s |
| Declination (J2000) | +58° 02′ 36″ |
| Space velocity (relative to the Sun) | 31.3 km/s |
In the sky
Too faint for the naked eye (magnitude 8.38); binoculars will find it. Visible from the whole Northern Hemisphere and south to latitude 32° S. North of latitude 32° N it never sets. It stands highest at midnight in September, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around 984 BC. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 53 million years.
The Sun seen from there
From a planet around HD 240237, the Sun would look like a star of magnitude 14.65, in the direction where our sky has the constellation Carina. It would be invisible to the naked eye.
Planets
- HD 240237 b 746-day orbit · 12.2 R⊕
Stellar parameters from the NASA Exoplanet Archive; position and brightness from the HYG / AT-HYG catalogue.