It always amazes me how people tend to ignore spotting scopes when they think astronomy. Seems like people either think binocular when it comes to astronomy or they think telescope, but somehow spotting scopes get bypassed altogether.
Fact is, a high end spotting scope from
Swarovski,
Kowa,
Leica,
Zeiss,
Pentax or
Nikon will provide better image quality within its magnification range than any giant binocular and be more versatile to boot. You don't get a two-eyed view, but you do get superb image quality and the ability to change magnification - features a lot of giant astronomy binoculars lack. Sure, the usual 60x isn't enough for serious planetary work, but even at that magnification I have seen cloud belts on Jupiter and crisp, high contrast views of Saturn's rings. Star clusters in one of the special glass versions look like a handful of diamonds against an inky black background. A wide-angle eyepiece will blow you away in the Sagittarius star clouds. I promise.
You'll also discover that these spotting scopes are more compact than any giant binocular and behave nicer on a standard photo tripod than the behemoths of the binocular world. Be advised, though, that angled spotting scope versions are much more comfortable to use for this application than straight body versions.
What I really like about spotting scopes for astronomy, though, is that you can always pull your spotting scope back out of the case the next morning and go birding with it. Try that with a 10" Dob. Ha!