PSR B1257+12 C
PSR B1257+12 C, alternatively designated PSR B1257+12 d and also named Phobetor, is a super-Earth exoplanet orbiting the pulsar Lich approximately 2,315 light-years (710 parsecs; 22 quadrillion kilometres) away from Earth in the constellation of Virgo. It was one of the first planets ever discovered outside the Solar System. It was discovered using the pulsar timing method, where the regular pulses of a pulsar are measured to determine if there is a planet causing variations in the data.
Size comparison of Phobetor with Earth and Neptune
(Based on selected hypothetical modeled compositions) | |
| Discovery | |
|---|---|
| Discovered by | Aleksander Wolszczan |
| Discovery site | Poland |
| Discovery date | 22 January 1992 |
| Pulsar Timing | |
| Orbital characteristics | |
| 0.46 AU (69 million km) | |
| Eccentricity | 0.0252 ± 0.0002 |
| 98.2114 ± 0.0002 d | |
| Inclination | 47 ± 3 |
| 2,449,766.5 ± 0.1 | |
| 108.3 ± 0.5 | |
| Star | Lich |
| Physical characteristics | |
Mean radius | ~1.5 R🜨 |
| Mass | 3.9 (± 0.2) ME |
| Temperature | 169 K (−104 °C; −155 °F) |
| |
In July 2014 the International Astronomical Union (IAU) launched NameExoWorlds, a process for giving proper names to certain exoplanets and their host stars. The process involved public nomination and voting for the new names. In December 2015, the IAU announced the winning name was Phobetor for this planet. The winning name was submitted by the Planetarium Südtirol Alto Adige in Karneid, Italy. Phobetor is, in Ovid's Metamorphoses, one of the thousand sons of Somnus (Sleep) who appears in dreams in the form of beasts.