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TDO 1, 2, 3, 4


TDO (Technology Demonstration Orbiter) is a series of USAF SMC missions to test technologies on orbit. It is a 12U CubeSat.

TDO 1 flew as a secondary payload on the aft bulkhead carrier (ABC) of the Atlas-5(551)¹ rocket launching AEHF 5. The mission was to test orbital debris tracking technologies. It was seperated before the main payload.

TDO 2 is the alpha numeric name of the multi-manifest small satellite vehicle flying with the AEHF-6 mission, is carrying multiple U.S. Government payloads that will provide optical calibration capabilities, which will support space domain awareness. The mission of TDO-2 is to support space domain awareness through optical calibration and satellite laser ranging. This capability will assist the nation's warfighters in performing their critical missions. TDO-2 was manufactured by Georgia Institute of Technology and sponsored by Air Force Research Laboratory.

Two more of these satellite, TDO 3 and TDO 4 will fly as a secondary payloads on the aft bulkhead carrier (ABC) of the Atlas-5(421)¹ rocket launching SBIRS-GEO 5. They are carrying multiple U.S. Government sponsored payloads that will provide critical experimental data for the United States Air Force Academy (USAFA). The Department of Astronautics at USAFA was the sponsor for TDO-3 and TDO-4. Both will be seperated before the main payload.

Nation: USA
Type / Application: Calibration
Operator: US Air Force (USAF) SMC
Contractors: Parsons ? (#1); Georgia Institute of Technology (#2)
Equipment: ?
Configuration: CubeSat (12U)
Propulsion: None
Power: None
Orbit: 208 km × 35264 km, 26.17° (#1); 200 km × 35459 km, 26.50° (#2)
Satellite COSPAR Date LS Launch Vehicle Remarks
TDO 1 (EZ 1) 2019-051B 08.08.2019 CC SLC-41 Atlas-5(551)¹ with AEHF 5
TDO 2 (EZ 2) 2020-022A 26.03.2020 CC SLC-41 Atlas-5(551)¹ with AEHF 6
TDO 3 (EZ 3) 2021-042B 18.05.2021 CC SLC-41 Atlas-5(421)¹ with SBIRS-GEO 5, TDO 4
TDO 4 (EZ 4) 2021-042C 18.05.2021 CC SLC-41 Atlas-5(421)¹ with SBIRS-GEO 5, TDO 3