And the answer, in honor of Friday’s release of Guardians of the Galaxy, is:
1) S/he was created by an English (from England) writing duo.
Cosmo was introduced by Dan Abnett and Andy Lanning in Nova #8.
2) Shares a vocation with Star Trek’s Lt. Worf.
Cosmo is the Chief of Security on Nowhere, the head of a dead Celestial which serves as a scientific research station at the edges of spacetime.
3) Loosely based on an “astronaut”.
The idea of Cosmo is based on the Soviet dogs that were sent into space during the early parts of the space race.
4) Despite appearances, s/he is a powerful telepath.
Cosmo is regularly seen using his telepathic skills in Guardians of the Galaxy.
5) S/he has brown hair.
Ok, it’s fur. I may have cheated a little on that one.
6) Has been a character in storylines involving Thanos, the Starjammers, Kang, the Inhumans, the Kree and the Shi’ar (not all at the same time though).
All of these storylines can be found in Guardians of the Galaxy. Seriously, it’s only 25 issues, everyone needs to read this run. It’s amazing.
Thanks to all of those who participated and a special shout out to Santana Perez for providing our first correct answer.