HAT-P-4 is 1,045 light-years from the Sun. The NASA Exoplanet Archive lists 1 planet around this F star; the first was found in 2007 by transit (HATNet).
Fly there in 3DHAT-P-4 b goes round its star every 3.06 days, 29 times as often as Mercury goes round the Sun.
HAT-P-4 is one of 2 stars in its system: the other is drawn where the Washington Double Star Catalog measures it on the sky.
| Spectral type | F |
| Surface temperature | 5,860 K |
| Mass | 1.248 solar masses |
| Radius | 1.596 solar radii |
| Luminosity | 2.698 times the Sun |
| Apparent magnitude | 11.118 |
| Age | about 3.9 billion years |
| Distance from the Sun | 1045.2 light-years (320.5 parsecs) |
| Position (J2000) | RA 229.9912°, Dec 36.2295° |
| Constellation | Boötes |
HAT-P-4 B is a G2 star of magnitude 11.53, judged a true companion. In 2016 it was 91.8″ from HAT-P-4, at position angle 164° (Washington Double Star Catalog, 15200+3614 MUG 15): 29,418 AU on the sky at this distance. The true distance can only be larger.
| Planet | Year | Orbit | Radius | Mass | Found |
|---|---|---|---|---|---|
| HAT-P-4 b | 3.06 days | 0.0444 AU | 14.28 R⊕ | 213.25 M⊕ | Transit, 2007 |
Values are the NASA Exoplanet Archive’s composite parameters. A radius marked estimated comes from a mass–radius relation; a mass marked minimum is M sin i. Planet sizes and colours in the 3D view are renderings: none of these worlds has been photographed as more than a point of light.