Lewis was selected in the NASA SSTI (Small Spacecraft Technology Initiative) program, along with Clark, to demonstrate advanced spacecraft technologies.

The spacecraft was 3-axis stabilized, zero momentum biased control system with 0.004 deg knowledge. A single solar array generated 600 W power at 1 year. The hydrazine propulsion system had eight 1-lbf thrusters. System reliability was 0.86 at 5 years. The primary ground station was at TRW, Chantilly VA, with receive only stations at Univ. Alaska, Fairbanks, Stennis Space Centre, MS, HBCU network. Data was archived by the Stennis Space Centre, and accessible on the Internet or via a T1 line. The payload included :

• Earth imaging Hyperspectral Imager (HSI) with 384 bands (0.4 - 2.5 µm, 30 m pixels, 7.7 km swath, panchromatic: 0.45 - 0.75 µm, 5 m pixels, 13 km swath)
• Linear Etalon Imaging Spectral Array (LEISA), from NASA GSFC (1.0 - 2.5 µm, 256 channels, 300 m pixels, 77 km swath)
• Ultraviolet Cosmic Background (UCB), from UC Berkeley (35 - 85 nm)

In addition to the above instruments, several spacecraft systems technologies were flown. These included a pulse tube cryocooler, a solid state recorder, a fiber optic data bus, GPS attitude determination, a wide FOV star tracker, a magnetically suspended reaction wheel, lightweight structure with integrated thermal control, and a GFRP overwrapped propellant tank.

Contract start was 11 July 1994. Satellite cost was $ 65 million including the TRW hyperspectral sensor. Athena launch cost was $ 17 million. The launch was delayed from the original 23 May 1997 due to launch vehicle problems. After launch, the satellite was spinning out of control. It lost power due to the solar panels not recharging the batteries. It was declared a loss on 25 August 1997.

Design Life: 3 years (required life is 1 year). Typical orbit: 523 km, circular, sun synchronous. Length: 1.77 m (5.80 ft). Maximum Diameter: 0.93 m (3.05 ft). Electrical System: Solar array. Electric System: 0.60 average kW.

• 1994 July 11 - Contract for Lewis satellite issued. -
  Lewis was selected in the NASA SSTI (Small Spacecraft Technology Initiative) program, along with Clark, to demonstrate advanced spacecraft technologies.

• 1997 August 23 - Lewis - Launch Site: Vandenberg. Launch Complex: SLC6. Launch Vehicle: Athena. Perigee: 124 km (77 mi). Apogee: 134 km (83 mi). Inclination: 97.50 deg. Period: 87.10 min.
  Reentered Sep 28