The first US lunar lander launched in more than five decades has experienced an anomaly preventing it from pointing its solar panels toward the sun, the company that built the robot said on Monday, January 8.

Astrobotic’s Peregrine lunar lander separated successfully from United Launch Alliance’s new Vulcan rocket overnight from the Cape Canaveral Space Force Base, and quickly established communications with NASA’s Deep Space Network of ground-based radio antennas.

All its systems powered on as expected, and it “entered a fully operational state,” Astrobotic said in a tweet. But “unfortunately, an anomaly occurred which prevented Astrobotic from achieving a stable sun-pointing orientation. The team is responding in real time as the situation unfolds and will be providing updates as data is obtained and analyzed.”

The lunar lander is experiencing a “critical loss of propellant,” making it almost certain to fail in its mission to touch down softly on the Moon, according to Astrobotic. “The team is working to try and stabilize this loss, but given the situation, we have prioritized maximizing the science and data we can capture,” Astrobotic tweeted. “We are currently assessing what alternative mission profiles may be feasible at this time.”

The lander’s documentation, available online, says that while in orbit, Peregrine’s top mounted solar panel stays pointed at the sun to enable maximum power generation. “The solar panel is utilized to provide battery charge and maintain lander and payload operations. After descent to the lunar surface the power system continues to provide reliable power services to payloads through the end of mission,” it says.

Peregrine is on its way to the moon and is supposed to hold its orbit before finally landing on a mid-latitude region called Sinus Viscositatis, or Bay of Stickiness, on February 23. Until now, a soft landing on Earth’s nearest celestial neighbor has only been accomplished by a handful of nations. But the United States and others are increasingly turning to the commercial sector to carry out routine missions and ship hardware at a fraction of the cost.