The Biggest Rocket Ever

Until now, history’s most powerful rocket was the Apollo program’s Saturn 5, which put out a prodigious 7.5 million lbs (3.4 million kgs) of thrust when its engines were lit. But when NASA’s new Space Launch System (SLS) thunders off the pad, six engines will generate 8.8 million lbs (4 million kgs) of power. The more powerful launch system is necessary for the larger spacecraft and heavier payloads that will be required for human exploration of the moon (under the new Artemis program) and Mars, as well as robotic missions to Saturn and Jupiter. In development since 2004, the SLS twice this summer disappointed space watchers when technical issues scrubbed its planned maiden launch. But NASA is determined to get the $4.1 billion rocket off the pad; it’s now scheduled for launch in November. “We’re going to keep to our schedule,” NASA Administrator Bill Nelson says.

Write to Jeffrey Kluger at jeffrey.kluger@time.com.