Al Clark-Asteroid (Book Five‪)‬

Just when you thought the series was over - Al Clark is back.
Our unassuming hero has reunited with his first wife after eighty-four years of being separated. Together, they embark on a new adventure of prospecting for rare elements from far-flung asteroids scattered around our solar system. They bought a servicable scout ship and hired a crew to fill their need for space exploration by visiting and researching possible candidates, and then selling the valuable information to clients interested in extraction. It's a pretty good gig.
Their plan worked perfectly until they crashed onto a desolate rock far from home, where they make a monumental discovery with the potential to revolutionize space travel.
All they have to do is repair their crippled ship and survive long enough to report their discovery.