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LEOStar is designed to be launched on a Taurus or Pegasus launch vehicle or in multiple or "piggyback" units on SELVS-II or smaller launch vehicles, Orbital's innovative LEOStar satellite platform supports payloads up to 360 kg and provides a three-to five-year mission life. The 12-sided bus is comprised of four decks: the deployment deck, payload deck, core deck and propulsion deck. The decks are connected together vertically by strong but light stringers, with shear plates attached to the 12 sides. The bottom and mid-decks house all primary spacecraft systems with the payload deck reserved for payload mounting.

Designed for flexibility, the LEOStar bus has been adapted to a variety of space science, remote sensing and technology validation missions. It features a large payload volume to handle multiple instruments and a pointing capability of up to 0.35 with pointing knowledge of up to 0.24, which can be dramatically enhanced by the addition of a star tracker.

To date, Orbital has built six LEOStar buses and has three more in production. The LEOStar bus was designed for low rate production line assembly and testing, which provides cost and schedule advantages through the uses of mature designs, familiar manufacturing and test equipment, dedicated and experienced personnel, and established vendor sources.

LEOStar's unique design offers frequent, cost-effective, launch-sharing opportunities. Depending on the payload height and complexity, for example, two LEOStar satellites readily fit within the Taurus, Athena, Delta-II and SELVS-I and II launch vehicles.

Originally designed as a common bus for the U.S. Air Force's Standard Technology Experiment Program (STEP) series of space technology missions, the LEOStar bus has supported five flight STEP missions and several other programs.

Customers can purchase the LEOStar spacecraft alone, or as part of a turn-key service that includes launch, operations and data delivery as well. For the OrbView-1 and OrbView-2 programs, based on other Orbital-built satellites, the company provided end-to-end services and is paid for delivery of data. Orbital produced the satellite bus, integrated two payloads and launched the satellite on a Pegasus, and is currently conducting mission operations from its own ground station, delivering data to principal investigators via direct downlink and the Internet.


  • Addition of star tracker provides improved pointing accuracy
  • GPS receiver provides onboard orbit knowledge with 30 m accuracy
  • Reconfiguration of solar array for Pegasus launch compatibility
  • Removal of propulsion system allows Pegasus launch
  • Mission operations

The LEOStar platform has been replaced by the LEOStar-2 bus

Satellite Date Launcher Weight (kg) Remarks
Launch BOL
Glory (ex VCL (ESSP 1)) 04.03.2011 F Taurus-3110 545
OrbView 3 26.06.2003 Pegasus-XL 304
STEP 0 (TAOS, USA 101, P90-5) 13.03.1994 Taurus-1110 503
STEP 1 (P90-1) 28.06.1994 F Pegasus-XL Launch failure
STEP 2 (SIDEX, P91-2) 19.05.1994 T Pegasus HAPS 180 Launch failure
STEP 3 (P92-2) 22.06.1995 F Pegasus-XL 268 Launch failure
STEP 4 (P95-1) 22.10.1997 Pegasus-XL 403
TSX 5 (P95-2) 07.06.2000 Pegasus-XL 250

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