Time to recalculate? Thor's hammer may be a featherweight

Thor hefting his hammer
Neil deGrasse Tyson's calculations that Thor's hammer weighs as much as 300 billion elephants may be off by about 300 billion elephants.

Astrophysicist Neil deGrasse Tyson brought Thor's hammer Mjolnir into the geek spotlight recently by running some calculations on its weight.
He shared his findings over Twitter, saying:
It's a good thing he said "if," as it's starting to look like he might be wrong. Suveen Mathaudhu is a program manager in the materials science division of the US Army Research Office. He pointed out to The Abstract of North Carolina State University that Thor's hammer is actually made from Uru, a fictional metal found in the faraway realm of Asgard.
"The critical mistake Tyson makes is thinking that Mjolnir was forged of the core of a dying star, when it was actually forged in the core of a dying star," Mathaudhu said. He shared some calculations of his own.
Mathaudhu took Mjolnir's dimensions from a Marvel trading card and estimated its density at 2.13 grams per cubic centimeter given a total weight of 42.3 pounds. That makes the hammer lighter than if it were made from aluminum. He went on to speculate that Uru could be a form of metallic hydrogen, which is thought to be present in the interiors of Jupiter and Saturn.
I'm sure Thor doesn't spend too much time pondering the weight of his hammer as he's out squishing bad guys, but it gives the rest of us something to think about. It also gives me a much better chance of hefting that weapon than if it weighed as much as 300 billion elephants. LINK