A spacecraft built and flown by Texas-based company Intuitive Machines landed near the south pole of the moon on Thursday, the first US touchdown on the lunar surface in more than half a century and the first ever achieved by the private sector.

The uncrewed six-legged robot lander, dubbed Odysseus, touched down at about 6:23 p.m. EST (2323 GMT), the company and NASA commentators said in a joint webcast of the landing from Intuitive Machines’ (LUNR.O), opens new tab mission operations center in Houston.

The landing capped a nail-biting final approach and descent in which a problem surfaced with the spacecraft’s autonomous navigation system that required engineers on the ground to employ an untested work-around at the 11th hour.

It also took some time after an anticipated radio blackout to re-establish communications with the spacecraft and determine its fate some 239,000 miles (384,000 km) from Earth.

When contact was finally renewed, the signal was faint, confirming that the lander had touched down but leaving mission control immediately uncertain as to the precise condition and position of the vehicle, according to the webcast.

“Our equipment is on the surface of the moon, and we are transmitting, so congratulations IM team,” Intuitive Machines mission director Tim Crain was heard telling the operations center. “We’ll see what more we can get from that.”

NASA Administrator Bill Nelson immediately hailed the feat as a “triumph,” saying, “Odysseus has taken the moon.”