Kevin Forsyth Home

 

History of the Delta Launch Vehicle



Current Delta News

(What about Delta IV?)

Archive for May, 2009


15-May-09 | Delta flight 341 – STSS-ATRR

A two-stage Delta II model 7920, sporting a 10-foot-diameter composite fairing, successfully launched on Tuesday, 5 May 2009, carrying STSS-ATRR into orbit for the Missile Defense Agency.

Given the mission’s “quasi-classified” status, United Launch Alliance was precluded from webcasting the launch, and the best source for on-site updates turned out to be—once again—Justin Ray’s Mission Status Center at Spaceflight Now. Official range liftoff time from SLC-2W at Vandenberg Air Force Base was 13:24:25.757 PDT.

MDA was understandably tight-lipped about specific details, including payload size, mass, and target orbit. Nevertheless, that did not prevent spaceflight expert Jonathan McDowell from speculating on its design and mass in the latest Jonathan’s Space Report, nor independent observers from locating what they believe is STSS-ATRR in a near-circular polar orbit, roughly 470 nautical miles in altitude.

Most importantly, very little has been said about its onboard sensors and their capabilities, leaving the public with only the most general description of the spacecraft’s mission: “the Space Tracking and Surveillance System (STSS) Advanced Technology Risk Reduction (ATRR) mission… is a space-based sensor component of a layered Ballistic Missile Defense System (BMDS) to detect, track, and intercept ballistic missiles.” [ULA Mission Book]

STSS-ATRR is a $400 million pathfinder for future BMDS missions, testing the technologies that—if proven viable—will be incorporated into upcoming operational satellites. Another technology demonstrator is slated to launch on a Delta II later this summer. Both missions have seen more than their share of delays and cost overruns.


     

Archives

Back to top