Re: How old is Thor?
Though Asgardians age much more slowly in the comics, they could take a different approach in the MCU. It could be that the Asgardians age at the same rate as human beings, but time passes by more slowly in Asgard than in our dimension. If every day in Asgard was equal to 40 earth days, Loki and Thor would both be in their mid to late 20s. That could make for an interesting plot point - Thor returns to Jane less than two weeks after saying goodbye, but to Jane it has been a year and one half.