Oberwerk (12x60) Binocular

Pros: Excellent optics, multi-coating, hand holdable, high magnification and large objectives.
Cons: A bit heavy.  Hard case unavailable.  Close focus at 30+ft may be unsuitable for birders.

Starting out with a 7x35, I came down with a case of "aperture fever".  My next purchase was the Oberwerk 15x70, which gave great views but absolutely needed to be mounted on a tripod.
The following year I purchased the 12x60.  Bingo!  This is the size for serious observing.  The view is quite comparable with the 15x70 in brightness and resolution, yet they can be handheld for several minutes at a time.  (It helps to have a chaise or comfortable outdoor chair). 
The optics are excellent, with BAK-4 prisms and multi-coated optics.
They are a bit heavy, but holding them up front near the objectives reduces the jiggle. 
They compare favorably with the much more expensive Fujinon 16x70.
If you only plan to buy one binocular for astronomy, this is the one to buy.
Other large binoculars are available, but for anyone 50 or older the 5mm exit pupil, high power, and 60mm objectives make a great combination for amateur astronomers.  Heartily recommended.