Cassiopeia

Cassiopeia was a constellation visible from Earth.

After the Krynoid on Earth was destroyed, the Fourth Doctor tried to take Sarah Jane Smith on a vacation to Cassiopeia. However, the TARDIS instead materialised in Antarctica as the Doctor had forgotten to reset the coordinates. (TV: The Seeds of Doom)

A Charged Vacuum Emboitment that shunted entropy from N-Space into E-Space existed in this constellation. When the universe was hanging by a thread and entropy was taking over, the Fourth Doctor and sent the reboot program from the Pharos Project on Earth to the CVE in Cassiopeia using a light speed overdrive. The signal arrived and restarted the CVE, stopping the entropy. (TV: Logopolis)

Many billions of years later, the CVE in Cassiopeia finally closed. (PROSE: Timewyrm: Apocalypse)

The Eleventh Doctor suggested Cassiopeia as a family vacation spot. He described it as "nice every time of year." (COMIC: Summer Wholiday)

The Meta-Crisis Tenth Doctor, while thinking of a new name for himself, considered calling himself "Cassiopeia", after the constellation. (PROSE: The Turning of the Tide)