Astrophysicist, and science superstar, Neil deGrasse Tyson isn't one to rest on his comic-book laurels. After helping Superman to locate his homeworld of Krypton in Action Comics #14, the director of New York City's Hayden Planetarium has moved on to a weightier question: Just how heavy is Thor's hammer?

Tyson raised the subject this week on Twitter, writing, "If Thor's hammer is made of neutron-star matter, implied by legend, then it weighs as much as a herd of 300-billion elephants." Alas, he didn't show his work, leaving Slate.com to break down the math (video below), multiplying maximum elephant weight by 300 billion.

The result? Mjölnir weighs 4.5 quadrillion pounds, which not only throws out of whack those strength scales in the Official Handbook of the Marvel Universe but makes us wonder whether in Thor #390 Captain America might've been using a little deer-antler spray along with the Super-Soldier Serum.

And in case you thought Tyson was making up his calculations, he provided photographic evidence that he conducted proper research. "Thor was kind enough to lend me Mjölnir so that I could make the proper measurements," he wrote.

Now if he could only answer who would win in a fight between Superman and the Hulk ...