This web page's content and links are no longer actively maintained. It is available for reference purposes only. NASA Official: Dr. Paul Mahaffy

Technical Specifications

Average Power

23.3 W, neutral mode; 20.9w ion mode; 13.1 W sleep

Package Size

20.3 cm (H) x 42.2 cm (L) x 36.5 cm (W)

Data Rate

1498 bps telemetry rate, 31.1 ms integration period, 34.0 ms total sample period

Mass Range

1-8, 12-99 Da

Electron impact ion source energy

70 eV, 25 eV


Two secondary electron multipliers operating in pulse-counting mode

Closed Source

Spacecraft speed enhanced sampling of non-reactive neutral gases (e.g. N2, factor 50); neutral source density >5x104 cm3

Open Source

Sampling of neutral gas, neutral radicals and ions with no surface interaction (e.g. N, H2CN+); neutral source density >2x105 cm3; ion flux >104 cm-2 sec-1