|Function||Small expendable launch system|
|Country of origin||United States|
|Height||19.21 metres (63.0 ft)|
|Diameter||1.67 metres (5 ft 6 in)|
|Mass||36,200 kilograms (79,800 lb)|
|Stages||4 or 5|
|Payload to LEO|
|Mass||580 kilograms (1,280 lb)|
|Payload to SSO|
|Mass||331 kilograms (730 lb)|
|Launch sites||Vandenberg SLC-8|
|First flight||27 January 2000|
|Last flight||15 June 2021|
|First stage – M55A1|
|Thrust||935 kilonewtons (210,000 lbf)|
|Second stage – SR19|
|Thrust||268 kilonewtons (60,000 lbf)|
|Third stage – Orion 50XL|
|Thrust||118.2 kilonewtons (26,600 lbf)|
|Burn time||74 seconds|
|Fourth stage – Orion 38|
|Thrust||34.8 kilonewtons (7,800 lbf)|
|Burn time||68 seconds|
The Minotaur I, or just Minotaur is an American expendable launch system derived from the Minuteman II missile. It is used to launch small satellites for the US Government, and is a member of the Minotaur family of rockets produced by Orbital Sciences Corporation (now Northrop Grumman).
The Minotaur I is the follow-on to the Orbital Sciences' Taurus (later re-named the "Minotaur-C") launch vehicle, combining the original Taurus's booster stage with a second stage from a Minuteman missile.
Minotaur I rockets consist of the M55A1 first stage and SR19 second stage of a decommissioned Minuteman missile. The Orion 50XL and Orion 38, from the Pegasus rocket, are used as third and fourth stages. A HAPS (Hydrazine Auxiliary Propulsion System) upper stage can also be flown if greater precision is needed, or the rocket needs to be able to manoeuvre to deploy multiple payloads. It can place up to 580 kilograms (1,280 lb) of payload into a 185-kilometer (115 mi) low Earth orbit at 28.5 degrees of inclination.
The Minotaur I is 69 feet tall and 5 feet wide.
Initially Minotaur I launches are conducted from Space Launch Complex 8 at the Vandenberg Air Force Base. Starting with the launch of TacSat-2 in December 2006, launches have also been conducted from Pad 0B at the Mid-Atlantic Regional Spaceport on Wallops Island.
There have been twelve launches of the Minotaur I, all successful.
|Flight||Date (UTC)||Payload||Launch pad||Trajectory||Result|
|1||January 27, 2000
|JAWSat (P98-1) (FalconSat1 / ASUSat1 / OCSE / OPAL)||Vandenberg SLC-8||LEO||Success|
|2||July 19, 2000
|MightySat II.1 (Sindri, P99-1) / MEMS 2A / MEMS 2B||Vandenberg SLC-8||LEO||Success|
|3||April 11, 2005
|4||September 23, 2005
|Streak (STP-R1)||Vandenberg SLC-8||LEO||Success|
|5||April 15, 2006
|COSMIC (FORMOSAT-3)||Vandenberg SLC-8||LEO||Success|
|6||December 16, 2006
|TacSat-2 / GeneSat-1||MARS LP-0B||LEO||Success|
|7||April 24, 2007
|8||May 19, 2009
|9||February 6, 2011
|USA-225 (NROL-66)||Vandenberg SLC-8||LEO||Success|
|10||June 30, 2011
|11||November 20, 2013
|ORS-3, STPSat-3 and 28 CubeSat satellites||MARS LP-0B||LEO||Success|
|12||June 15, 2021