QUESTION:
Did we find out from these images how thick Neptune's atmosphere is?

ANSWER from Heidi Hammel on June 3, 1996:
We already had a pretty good idea how thick Neptune's atmosphere was;
these images did not change that.  What these new images did tell us was
how the weather on Neptune changes with time.  We had a few ideas about
that, but very little information about how the clouds change over
timescales of years.  That is because even though we have been looking
at Neptune for a long time, we didn't have a powerful enough telescope to
really see its clouds clearly from Earth until Hubble was created
(remember - Neptune is the most distant planet right now - it is very
very far away).  The Voyager pictures were so good because that spacecraft
flew right by Neptune when it was taking pictures, but it was only close
by Neptune for a few days!

What we learned was that for the past two years, the weather has been
pretty quiet on Neptune - there were definitely some clouds, but not any
really huge storms.  We didn't know that until these pictures were taken.
This information will help us understand the climate on Neptune.