schematic of Dawn solar panel span

Key Spacecraft Characteristics:

  • Extensive redundancy using flight-proven assemblies from other Orbital and JPL spacecraft
  • Ion propulsion system, based on the design validated on Deep Space 1
  • Two 100 W (RF) traveling wave tube amplifiers, fixed 1.5 m high-gain antenna, 3 low-gain antennas, two small deep space transponders
  • Solar array capable of producing more than 10 kW at Earth's distance from the Sun and more than 1 kW at Ceres's maximum distance
  • Flight proven attitude control system used on Orbview, TOPEX/Poseidon ocean topography mission, and Far Ultraviolet Spectroscopic Explorer
  • Simple hydrazine reaction control subsystem with two sets of six 0.9 N engines used on the Indostar spacecraft
  • Command and data handling uses off the shelf components as used on the Orbview program
  • Modular flight software based on design used on Orbview
  • Core structure is graphite composite. Panels are aluminum core, some with aluminum facesheets and others with composite facesheets.

Spacecraft Diagram:


This figure depicts the Dawn flight system. Upper views are the same scale.


  • HGA – High Gain Antenna
  • LGA – Low Gain Antenna
  • CSS – Coarse Sun Sensors
  • GRaND – Gamma Ray and Neutron Detector
  • IPS Thrusters – Ion Propulsion Thrusters
  • RCS Thrusters – Reaction Control System Thrusters
  • VIR – Visible and Infrared Mapping Spectrometer
  • FC – Framing Camera

- Learn about Dawn's ion propulsion
- Read published article describing the mission: Dawn: A mission in development for exploration of main belt asteroids Vesta and Ceres