 Radial velocity changes over time of 14 Andromedae caused by the orbit of 14 Andromedae b. | |
| Discovery[1] | |
|---|---|
| Discovered by | Satoet al. |
| Discovery site | Okayama Planet Search Program |
| Discovery date | July 2, 2008 |
| Doppler Spectroscopy | |
| Designations | |
Named after | "spe" from latin "spes" meaning hope |
| Spe | |
| Orbital characteristics[2] | |
| 0.775 AU (115,900,000 km) | |
| Eccentricity | 0.0094 |
| 186.76+0.11 −0.12 d | |
| 2452853.0±2.1 | |
| Semi-amplitude | 86.08+2.76 −2.95 m/s |
| Star | 14 Andromedae |
| Physical characteristics[2] | |
| Mass | ≥3.559+0.114 −0.122 MJ |
14 Andromedae b (abbreviated14 And b), formally namedSpe/ˈspiː/, is a candidateexoplanet approximately 248light-years away in theconstellation ofAndromeda.
The 186-dayperiod planet orbits about 83% theEarth-Sun distance from the giant star14 Andromedae. It has aminimum mass of 3.559 times the mass ofJupiter. The planet orbits with an eccentricity of 0.0094, which means the orbital distance over the course of its revolution varies by only 0.02AU.[1]
In July 2014 theInternational Astronomical Union launchedNameExoWorlds, a process for giving proper names to certain exoplanets and their host stars.[3] The process involved public nomination and voting for the new names.[4] In December 2015, the IAU announced the name Spe for this planet.[5] The winning name was based on that submitted by theThunder Bay Centre of theRoyal Astronomical Society of Canada[6]); namely 'Spes',Latin for 'hope'. (Spes was also theRoman goddess of hope.) The IAU substituted theablative form 'Spe', which means 'where there is hope', to match that given to the host star at the same time.[7]
The preprint announcing 14 Andromedae b was submitted to thearXiv electronic repository on July 2, 2008, by Bun'ei Sato and collaborators, who discovered it using theDoppler Spectroscopy method, during theOkayama Planet Search radial velocity survey of G and K giants atOkayama Astrophysical Observatory.[1]
A 2023 study of planets around evolved stars, while presenting updated parameters for this planet, found that the radial velocity variations are correlated with stellar activity signals, casting doubt on the planet's existence.[2] Based on this, a 2024 study listed it as one of several doubtful planets around giant stars (along with the other named planets41 Lyncis b and42 Draconis b).[8]
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