Avengers Annual #7

"The Final Threat"

1977, in collection

The Avengers stop Thanos from destroying Earth's sun, Adam Warlock is killed

marvel.com

continues in

cover
* Marvel Two-In-One Annual #2 "Death Watch!" 1977, in collection (1977*) The Thing, Spider-Man, and the Avengers stop Thanos from destroying Earth's sun

reprinted in

* 40 Years of Avengers 2006, in collection (2006*)
* Greatest Battles of the Avengers TPB 1993, in collection (1993*)
* Marvel Digital Comics no date (no date)