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On this day – May 20

Posted on May 20, 2025May 9, 2025 By Barb Sande

The events on this day in history for our heritage companies are noted below.

The earliest event was in 1960, the latest event was in 2015

Five milestone events (5 to 65+ years ago)

Human Spaceflight:

NONE

Military and Classified Programs:

1970 – LAUNCH: Lockheed Corona 138, Thor SLV-2H/Lockheed Agena D, SLC3W, VAFB – MILESTONE: 55 years ago

1972 – LAUNCH FAILURE: Classified mission, MM Titan 24B, SLC4W, VAFB

1975 – LAUNCH FAILURE: DSCS II-05, 06, MM Titan IIIC, LC40, CCAFS – Transtage attitude control lost – MILESTONE: 50 years ago

2015 – LAUNCH: USA-261/Cubesats, ULA Atlas V 501, LC41, CCAFS – MILESTONE: 10 years ago

Exploration and Interplanetary Programs:

1978 – LAUNCH: Pioneer Venus Orbiter, GD Atlas SLV-3D/Centaur, LC36A, CCAFS

Earth-Monitoring and Civil Weather Satellite programs:

1965 – LAUNCH: RCA DSMP Block 4A F3, Thor Burner 1, SLC10W, VAFB

2005 – LAUNCH: LM NOAA-18 (N), Delta 7320-10C, SLC2W, VAFB – MILESTONE: 20 years ago

Commercial Programs:

1999 – LAUNCH: LM Nimiq-1, Proton-K/DM-2M, LC81/23, Baikonur, Kazakhstan 

Test, ICBM, FBM programs:

1960 – LAUNCH: GD Atlas D, LC12, CCAFS – MILESTONE: 65 years ago

1969 – LAUNCH: MM Titan II VAFB 395-B

1986 – LAUNCH: Lockheed Poseidon C3, SSBN659, ETR

Other:

NONE

The photo today is of the Atlas SLV-3D/Centaur on the pad just before the launch of Pioneer Venus Orbiter in 1978.  Photo Credit: NASA. 

May 20 – Atlas SLV-3D on the pad just before launch of Pioneer Venus Orbiter. Photo Credit: NASA.
On This Day

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