HD 219134 d
| Discovery | |
|---|---|
| Discovery site | HARPS-N of the Telescopio Nazionale Galileo | 
| Discovery date | 2015 July 30 | 
| radial velocity method (HARPS-N); | |
| Orbital characteristics | |
| Apastron | 0.2697 (± 0.0059) AU | 
| Periastron | 0.2043 (± 0.0059) AU | 
| 0.2370 (± 0.003) AU | |
| Eccentricity | 0.138 (± 0.025) | 
| 46.8590 (± 0.028) d | |
| Inclination | null | 
| Star | HD 219134 | 
| Physical characteristics | |
| >1.61 (± 0.02) R🜨 | |
| Mass | >16.17 (± 0.64) M🜨 | 
| Mean density | <21.4 g cm−3 | 
| <6.24 g | |
| Temperature | 410.5 K (137.4 °C; 279.2 °F) | 
HD 219134 d, also known as HR 8832 d, is an exoplanet orbiting around the K-type star HD 219134 in the constellation of Cassiopeia. It has a minimum mass over 16 times that of Earth, indicating that it is likely a Hot Neptune. The exoplanet was initially detected by the instrument HARPS-N of the Italian Telescopio Nazionale Galileo via the radial velocity method. Unlike HD 219134 b and HD 219134 c it was not observed by the Spitzer Space Telescope and thus its radius and density are unknown. Only a minimum possible radius can be given.