The Centaur upper stage that sent four magnetospheric probes into an elliptical orbit around Earth re-entered the atmosphere on August 28, 2017 after slowly decaying from orbit over the course of two and a half years. Launching atop an Atlas V 421 rocket, Centaur lifted the satellites into a 585 by 70,100-Kilometer orbit before slightly lowering its orbit to speed up its decay.
NORAD ID: 40486
Object: Atlas/Centaur R/B
Type: Centaur Upper Stage
Dry Mass: 2,243 Kilograms
Launched: March 13, 2015 – 02:44 UTC
Launch Vehicle: Atlas V 421
Launch Site: SLC-40, Cape Canaveral Air Force Station
Re-Entry Prediction: August 26, 2017 – 15:01 UTC +/-7 Min.
Re-Entry Zone: Atlantic Ocean