Scientists strongly lean Democratic, according to this Pew study.
http://www.people-press.org/2009/07/09/section-4-scientists-politics-and-religion/55% of scientists are lean democrats; 6%(!) are republicans. Counting in leaners, the figure is about 81% democratic.
As such, I would expect science postgrads to have strongly supported Obama.
Some reasons for this:
a) A large proportion of scientists work in the public center
b) They are disproportionately agnostic; almost none are evangelicals (see chart at bottom).
c) Scientists of today (as opposed to say, 150 years ago) are much more interconnected throughout the globe. There is much less nationalistic rivalry as opposed to that between Germany and Britain in the early 20th century. Thus, they are strongly internationalist (and therefore do not take kindly to anti-UN rhetoric).
d) They spend longer getting degrees, therefore more time is spent in predominantly liberal postgrad cities.
So from what it seems here, most postgrads in scientific fields, including (and perhaps especially) astronomy are liberal. They would have strongly supported Obama.
Doctors, however, do not seem to be as liberal. I see more of a liberal trend occurring over several decades, in part a result of the general educational elite moving towards the democrats. However, doctors are more conservative than scientists probably because they operate in a more corporate setting; there is less public sector influence.