Every Celestis Memorial SpaceFlight mission is given a distinctive name, symbolizing unique aspects of the mission and honoring the participants aboard. The seventeenth Celestis Mission is named The Horizon Flight - in recognition of the orbital parameters of the SherpaFX1 spacecraft that carries the Celestis Flight Capsules into space. The Falcon 9 rocket will place Sherpa FX1 into a sun-synchronous polar orbit, meaning that Sherpa will cover the entire surface of the Earth every few days.
Thus, in a very real sense, Sherpa FX1 - and the Celestis capsules - will always be just over the Earth’s horizon as it makes its multi year journey, and hence the mission name.