Watch the Falcon 9 light its engines for a static test fire (members only)

The twin 177-foot-tall solid-fueled boosters for the first flight of NASA’s Space Launch System have been stacked inside the Vehicle Assembly Building at the Kennedy Space Center to await arrival of the rocket’s cryogenic core stage, which is set for a second engine test on a firing stand in Mississippi later this month.

Held down by heavy-duty restraints, a Falcon 9 rocket fired up its nine Merlin engines for more than three seconds Thursday evening in a key readiness test before launching with a commercial television broadcast satellite next week.

NASA has decommissioned a long-lived satellite launched in 2000 that demonstrated remote sensing and surveying instruments and techniques common in today’s orbiting Earth observatories.