The Agency wanted to send people to Pluto, because that's the sort of thing the Agency was designed to do. However, like all publicly-funded organizations, the Agency was always short of cash, and the cost of sending a team of researchers to Pluto and bringing them back again was prohibitive. The Agency, though, was known for its creativity, and some bright soul at the Proposals Division had the radical idea that you could reduce the cost of a Pluto mission dramatically if you didn't bring the researchers back. In fact, you could cut the cost by about 95% if you just sent a single person, and then left him on Pluto for the rest of his life.
The Proposals Division started putting its proposal together, and one of the preliminary items they investigated was whether you could, in fact, maroon someone six billion kilometers from the Earth and expect him to remain sane. They consulted some psychologists, and the psychologists told them that, yes, you could send someone with a particular type of personality out to Pluto on a permanent basis, and that personality type would remain sane, if you used the word "sane" in its broadest possible sense. It would have to be an extreme misanthrope, someone who didn't like being around other people, and who would, by choice, remain as isolated as possible. To such a person, the thought of being six billion kilometers from the rest of humanity would be like living in paradise.
Of course, in order to function in a useful manner at a research outpost, such a person would also have to be technically proficient to a certain extent, and would have to have methodical habits. This set severe limits on the number of prospective candidates. Before the proposal could go ahead, the Proposals Division would have to know in advance that they could secure a volunteer for the Pluto mission.
And so they came to me.
Fortunately for the Proposals Division, their email was able to make its way through the various filters I have on my account, and the subject line was intriguing enough that I didn't delete it sight unseen. I read their proposal, and sent them a brief response indicating that I would be willing to take part in their mission. It seemed like a low probability event to me, so after I sent my reply, I deleted the email and let the matter drop from my mind. Five minutes later, I had forgotten all about it.
Wheels turned, and documents passed hands, and in due course the mission to Pluto was approved by the relevant authorities. About a year and a half had passed, and I hadn't given the Pluto mission another thought. I had added a couple more filters to my email account, and this time the Agency's email didn't make it though. I have no telecom system, so in the end they had to send someone to my house in the Hebrides. Fortunately for them, I was in a sociable mood that day, so I answered the door and listened to them. We talked at the door for five minutes and then they went away, and I had volunteered to go to Pluto.