The Sun is the star at the center of the Solar system.
S.H.I.E.L.D. operated a program known as Slingshot, in which dangerous objects were launched into the sun to be destroyed. One such launch occurred in 2013 and was watched by Coulson's Team. However, the rockets were empty, as the objects were in fact in the Fridge. S.H.I.E.L.D. occasionally sent a monkey in the rockets for fun.
Erik Killmonger's Demise
In the wake of his defeat at the hands of T'Challa, Erik Killmonger left the Great Mound to watch the sunset in Wakanda, which he had been told by his father were the most beautiful in the world. Killmonger watched the sunset as he died.
In K'un-Lun, Danny Rand and Davos had their duel to determine who would win the title of Iron Fist. The pair were equally matched, resulting in a long duel. As the sun rose, Rand led Davos into the light and blinded him using it, giving Rand the upper hand and allowing him to win the duel.
In 2018, S.H.I.E.L.D. had made a plan to destroy the Gravitonium by launching it directly into the Sun before he could be used once again by HYDRA, as they intended to use Zephyr One to slingshot it out of their atmosphere. However, as the Gravitonium had been absorbed into Glenn Talbot's body, causing him to gain super powers and then go on a rampage, Quake was forced to battle Talbot, resulting in her using her enhanced power from the Centipede Serum to launch him into space, where Talbot's body then floated into the sun, which had finally killed Talbot and destroyed all the remaining Gravitonium.
Ikaris attempted to stop his fellow Eternals from preventing Tiamut the Communicator's Emergence, which would have destroyed Earth. However, Ikaris and Sprite failed, eventually choosing to join the Uni-Mind. Distraught over having betrayed his creator, Arishem the Judge, Ikaris chose to kill himself by flying into the Sun. He approached the Sun and closed his eyes as he got consumed by the flames, dying.
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