is myr roughly the same as mya in amount?
yes
what does mya stand for?
million years ago
and myr?
million years
how many teraseconds does it represent?
31.6
do they use it in astronomy?
yes
how about in geology?
no
is there a debate between myr and mya usage?
yes
which one is favored?
the term "Ma"
is myr avoided?
yes
how do they do that?
one avoids "myr" and simply adds "ago" explicitly
which iso does ma conform to?
ISO 31-1 (now ISO 80000-3)
what NIST recommended practice does it conform to?
NIST 811