NASA Parker Solar Probe is an active solar observatory spacecraft that became the first spacecraft to fly through the Sun's corona. Its integrated blowdown monopropellant hydrazine propulsion subsystem uses twelve 4.4 N thrusters for attitude control and trajectory-velocity maneuvers, including trajectory corrections and reaction-wheel momentum unloading. NASA lists 685 kg spacecraft mass at launch.
Future launches and major activity directly linked to this vehicle family.