"SR387" is the conjectural name for an unidentified planet briefly shown in Metroid Fusion.
It is a planet situated in a far-off sector which has an unknown designation at this point, sharing a solar system with SR388. Its orbit is very close to SR388's orbit, suggesting that it may also fall within the habitable zone of the system star, which would also suggest that it is capable of supporting life.
Only basic facts about the planet can be observed, because the sector grids are the only appearance of the planet within the entire Metroid series: the planet appears to have a small ring system similar to Saturn, and a slower revolutionary period than SR388.
|Planets in the Metroid series|
|Bilium | Oormine II | Tallon IV | Twin Tabula | Zebes|
|Alinos | Arcterra|
|Aether | Dark Aether|
|Federation Solar System|
|Bryyo | Elysia | Norion|
|Unknown Solar System|
a.k.a. Planet SN-883 or Urtraghus ("large booty")
|SR388's solar system|
|SR388 | "SR387"|
|Earth | Jupiter|
|Excelcion | Talvania | Bion|
|Outlaw | Maru | Agricultural world | Jatsuk | Ocean world |
Graveyard planet | Galactic ruins
| 2466 URSA | Bes III | Devon III | Daiban | Demon Planet | Degrade |
Jamoru | Jasdam | Jigrad | K-2L | Kankei | Liberty
Mondreus | Naishii | Nest | RX 338 | Solairon 12 | Tivus | Vho