The astrophysicist ponders the nature of Thor, Hulk and more.

Neil deGrasse Tyson was on a superheroes kick Thursday and began throwing out some thoughts about the Avengers via social media. It all started around 7:30 a.m. when the astrophysicist and TV personality tweeted, "Some accumulated comic book reflections follow, if anybody’s interested…" The Cosmos: A Spacetime Odyssey host explained he is more of a Marvel fan over DC because "many of their superheroes started as scientists, or derive their powers from authentically fictional (rather than fantastically magical) science concepts." Still, he had some thoughts, which started with a picture of Chris Hemsworth as Thor. "Seems to me, if Thor is a god, with godlike powers, then he doesn't really need big muscles," Tyson quipped.

Another Thor note involved Mjölnir, the character's iconic hammer. "In 1991 Marvel introduced a Thor’s Hammer trading card declaring Mjölnir to be made of the Asgardian metal Uru, weighing 42.3 lbs — but they didn’t specify where in the universe. That weight on the Mars moon Deimos, for example, corresponds to 140,000 pounds on Earth," he said. As far as the Hulk, Tyson wanted to talk about his transformation from man into beast. "If Bruce Banner retains his original mass when he expands to become the Hulk, then his body must become less dense. If so, then in his Hulked state, he'd have the density of a champagne cork. I’m just sayin'," he wrote. It wasn't all Marvel, though. Tyson threw some love DC's way, noting he was featured in Action Comics (Volume 2) No.14 when Superman visited his office at the Hayden Planetarium in Metropolis. (Tyson also cameoed in 2016's Batman v Superman: Dawn of Justice).