Delta B

The Delta B, or Thor-Delta B was an American expendable launch system used for nine orbital launches between 1962 and 1964.^[3] A derivative of the Thor-Delta, it was a member of the Delta family of rockets.^[4]

Delta B prior to the launch of TIROS-8
Function	Expendable launch system
Country of origin	United States
Capacity
Payload to LEO
Altitude	350 nautical miles (650 km; 400 mi)
Mass	800 pounds (360 kg)[1]
Payload to Earth escape trajectory
Mass	130 pounds (59 kg)[1]
Launch history
Status	Retired[2]
Launch sites	Cape Canaveral LC-17[3]
Total launches	9
Success(es)	8
Failure(s)	1
First flight	13 December 1962
Last flight	19 March 1964
[edit on Wikidata]

The first stage was a Thor missile in the DM-21 configuration, and the second stage was the AJ10-118,^[1] which was derived from the earlier Delta-A.^[4] An Altair solid rocket motor was used as a third stage.^[1]

All nine launches occurred from Cape Canaveral Air Force Station Launch Complex 17.^[3] Most of the launches carried communications satellites, including Syncom-1^[2] and Syncom-2.^[2] Syncom-1 was intended to be the first satellite to be placed into a geosynchronous orbit, however the spacecraft malfunctioned prior to reaching this orbit.^[5]Syncom-2 subsequently became the first geosynchronous satellite,^[5] and was placed at 55° west of the Greenwich Meridian. The final launch failed due to third stage underperformance,^[6] all other launches were successful.^[3]