Distances and phases on
Change units
**The use of Solar Electric Propulsion (SEP) on the Psyche mission makes it difficult to predict exact mission milestone times until much closer to those events than for a mission which traditional chemical propulsion. SEP provides much lower thrust than chemical propulsion and, therefore, is operated over a very long time (over 80% of the time in the case of Psyche). Additionally, for SEP, there is an intricate and fascinating interplay between mass, solar power, and timing/duration of thrusting (more here). Therefore, rough mission milestones are communicated, which will be refined when the respective events approach. For practical purposes of this website, the 15th of the respective month is assumed for the countdowns. They are not predictions. The actual dates will be updated once they become available. More information about how SEP works can be found here, here, and here.
This page was created by Raphael Marschall, @spaceMarschall, www.spaceMarschall.net and is not an official channel of communication by NASA or the Psyche mission.