Is the U-235/U-238 ratio different from Earth's? Surely they have that data from the mass spec? Naively I'd think that's the most direct, incontrovertible way o

Is the U-235/U-238 ratio different from Earth's? Surely they have that data from the mass spec? Naively I'd think that's the most direct, incontrovertible way of distinguishing an extrasolar meteorite from some geochemistry process that enriches and depletes different elements.