Controllers at the Goddard Space Flight Center in Greenbelt, Maryland, will send commands at 9:54 p.m. Eastern Daylight Time (Wednesday, 01:54 GMT) ordering six of the spacecraft's 12 thrusters to fire for about 30 minutes.
That will drop the satellite's orbit from its current altitude of 316 miles (510 kilometers) to 217 miles (350 kilometers) above Earth.
Three additional 30-minute burns are scheduled -- one Wednesday night, May 31 (Thursday morning GMT) and two early Sunday, June 4 -- to bring the 17-ton, school bus-sized Compton crashing into an uninhabited part of the eastern Pacific Ocean.
Compton is expected to crash June 4, about an hour after the last burn, in an area about 2,500 miles (4,025 kilometers) southeast of Hawaii.
It will be the largest spacecraft to burn up in Earth orbit since Skylab in 1979. More than 6 tons of Compton debris -- ranging from fragments of a few ounces to chunks weighing several hundred pounds -- are expected to survive the plunge.
Last Sunday, Goddard controllers test-fired Compton's thrusters for 1 to 2 seconds to make sure they performed properly.
NASA is bringing the nine-year-old satellite to an end because one of Compton's three stabilizing gyroscopes has failed. The space agency fears that another gyroscope failure would render the Compton uncontrollable, reducing NASA's ability to manage its fall from orbit -- and determine its impact area on Earth.
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