Help! Space opera written by women?

I was at Galaxy Books today, shopping for a gift. I've had a bit of a hankering for space opera recently, so I figured while I was there I'd pick up something to satisfy that urge. Naturally, I went looking for something written by a woman.

It turned out to be a real challenge. I don't often go into bookstores completely cold, but space opera has always been easy to find: just look for the books with spaceships on the cover. And, honestly, if you just cast your eye casually across a shelf in the science fiction section, you're bound to see lots of spaceships.

I noticed today that whenever I let my eye wander to a random section of shelf, I'd end up staring at a book written by a man. I eventually had to start working my way systematically through the shelves just to find the books written by women. Obviously I knew that there were more science fiction books written by men than women, but I think I've avoided being directly exposed to that fact this year by always going in prepared, with a list of specific authors I was looking for. Today really brought home how huge the gender discrepancy is in sci-fi publishing; suddenly, my male-dominated reading history seems a bit unsurprising. Which is sad.

(Also, is it just me, or are science fiction novels written by women much more likely to have people -- especially women -- on the cover than science fiction novels written by men?)

I ended up walking out the door with Undertow [2007], by Elizabeth Bear. I expect I'm going to enjoy it -- Dust [2007] and Chill [2010] have been two of this year's highlights for me -- but I confess I was a little disappointed. I already know Elizabeth Bear is great; what I was looking for was space opera written by somebody who was new to me.

So, if you're reading this, help me out! Throw your suggestions for good space opera written by women into the comment thread below. I tried Google, but I just came up with lots of lists of books written by men. What should I be reading?