The first draft of Mars is finished. Word count is a little over 58,000. I have some things to add in during second-draft revision, so I'm predicting a final word count in the 62,000-65,000 neighborhood. This will make it a little shorter than Venus but a little longer than Mercury. And, of course, all that could change depending on what the beta readers say.
My goal was to complete the first draft in four weeks or less. I completed it in 24 days. Mission accomplished. :D
My next goal is to outline the entire Wheel of Fire series before April 1. I've already done a lot of world-building. Last night, I rearranged some of the series arc. The series is now planned as eight books, not nine.
So Mars is going on the back burner for the next month. When April arrives, I'll return my focus to the Free Space trilogy. The year is still young, but 2016 has started out satisfyingly productive.