The five spin-stabilized (T spin =3s) probes carry identical instruments which exceed the requirements of the primary science objective.

The guiding principles are:

• Selection of existing, low power, low weight units, to ensure no new development costs,
• Common instrument DPU (IDPU) electronics to maximize science and simplify interfaces, motivated by FAST,
• “Common buy” parts procurement to minimize expenditures
• Significant foreign contributions in instruments and analysis, ensuring wide international community participation, and
• Rapid, web-based dissemination of data and IDL analysis code accompanied by a $4M guest investigator program to ensure maximum benefits for the US science community.

The instruments being flown are:

• Fluxgate magnetometers (FGM)
• Electrostatic analyzers (ESA)
• Solid state telescopes (SST)
• Search coil magnetometers (SCM)
• Electric field instruments (EFI)

The instruments on the ground consist of:

• Fluxgate magnetometers (FGM)
• All-sky white light imagers

THEMIS All-sky Imager		FAST ESA Module