NASA and the National Oceanic and Atmospheric Administration (NOAA) have launched the first of four Joint Polar Satellite System (JPSS) satellites, which are designed to provide more accurate weather forecasts than existing polar-orbiting satellites.

JPSS-1 lifted off on a United Launch Alliance (ULA) Delta 2 rocket from Vandenberg Air Force Base in California at 1:47 a.m. Pacific time Nov. 18. About 63 minutes later, the satellite deployed its solar arrays and was operating on its own power. The Delta 2 also dispensed five research cubesats for NASA.

JPSS-1 is slated to undergo three months of tests before becoming operational.

A series of factors – a launch safety alarm, the presence of boats near the launch site, a faulty battery in the launch vehicle booster and high winds – combined to delay the launch by eight days.

Ball Aerospace [BLL] built JPSS-1 and Raytheon[RTN] provided the ground system. Ball, Harris Corp.[HRS], Northrop Grumman [NOC] and Raytheon provided the spacecraft’s sensors.

Orbital ATK [OA] is building JPSS-2, which is slated for a 2021 launch.

ULA, a joint venture between Boeing [BA] and Lockheed Martin [LMT], said the JPSS-1 launch was the second to last mission for the Delta 2, which has had 154 launches since its introduction in 1989. The rocket’s final mission is for NASA’s ICEsat-2 Earth-observing satellite in 2018.