PLUTO is the final stop on the Grand Tour taken by Ben Bova of our Solar System. This story also rounds off the Outer Planets trilogy. As Ben Bova passed away in 2020, the publishers enlisted Les Johnson, another award-winning SF author, to finish the story. While some earlier incidents are mentioned, this work stands well alone for readers.

Major Larry Randall arrives with a rescue mission to Pluto. A scientist from a research vessel, Dr. Aaron Mikelson, is happily trundling around the dwarf planet’s surface, ignoring all calls to return. He is the survivor of a terrible accident and now lives half-human, half-AI, supported by machines like the Rover. The other scientists feel Mikelson’s mind has warped and a week on Pluto’s rocky, icy ground has left him in a bad place.

Aboard Tombaugh, the research ship, the Space Force Major is only suffered to speak because, unlike his peers, he has a PhD. The scientists, who are of a particular mindset, if they are willing to come all the way out to the edge of the Solar System, just want the crew of Aurora to retrieve Mikelson and go away again. The major asks Dr. Abigail Grigsby to call him Larry. She won’t do that in front of anyone else. At the same time, new faces are welcome on a six-month expedition for both ships.

The action really heats up halfway, when a strange, dense object is uncovered and the scene shifts to Pluto’s largest moon, Charon. In previous books, we saw that alien visitors had deposited odd items in places like the bottom of a sea on Neptune. No surprise if they did it again on a Kuiper Belt body. Ben Bova used to write by exploring along with his characters. Les Johnson asks what might go wrong if an alien artefact of indeterminate age were uncovered, on Pluto or Charon. Personally, I would leave it the heck alone. I would not go poking it, providing it heat, and I would not, repeat not, bring it aboard the spaceship. So why would even crazy scientists do these things? The stimulus is that Russia and China have sent armed research vessels scooting out to Pluto, and they might grab it first. I say, let them have it, and whatever consequences.

PLUTO is a short novel, in keeping with the size of the location, and the planetary science described nicely rounds off The Grand Tour. We see that there are plenty more dwarf bodies to explore, and people will likely be doing this for the foreseeable future. I can only hope they don’t poke every object they find. Fans of the series will be pleased to complete the official trip with Ben Bova and Les Johnson.