USS Constellation (NCC-1017) was a Constitution-class heavy cruiser that was in service with Starfleet in mid-23rd century. In 2267, the Constellation and her crew of 430 were under the command of Commodore Matt Decker.
In that year, on stardate 4202.1, while on routine deep space exploration, the Constellation encountered several destroyed star systems, including systems L-370 through L-374. Although exceptionally heavy subspace interference prevented contact with Starfleet, the ship began to investigate.
Upon entering the L-374 system, the ship's science officer, Masada, discovered that L-374 IV was breaking up. Upon closer inspection, an enormous robot was found hovering over it, slicing out chunks of the planet with an antiproton beam.
While attempting to intervene, the Constellation was attacked by the planet killer. The ship's deflector shields were easily pierced and the resulting damage crippled the ship, forcing it to hide in the inner system. Nearly without power, all but defenseless, and with the life support system failing, Decker ordered his crew to abandon ship and beam down to L-374 III where they could take refuge. The commodore remained behind to operate the transporters. Attempts to contact Starfleet failed and a distress call was sent out.
The robot attacked the Constellation once more, knocking out the transporters and stranding Decker on the ship alone. The robot then proceeded to devour L-374 III, killing the remainder of the ship's crew. The deaths of 430 of his crew would have a severe psychological impact on the commodore.