| PLANET | |
| P4X-351 | |
 P4X-351 | |
| Classification: | Class M |
| Affiliation: | Federation, Starfleet |
| Location: | Alpha Quadrant |
| Dominant Species: | Human |
| Length of day: | 24 hours |
P4X-351 was a planet in the Milky Way galaxy on which the Federation outpost of Icarus Base resided. The planet was 21 light years from Earth. The location of the planet was provided to the Federation by an undercover operative within the Lucian Alliance.