The Japan Aerospace Exploration Agency’s spacecraft, launched Wednesday on Nasa’s Artemis I mission, has been plagued by communications problems since it separated from the Space Launch System rocket that night. Jaxa hoped to attempt a landing as soon as Monday night if all went well, but the agency failed to restore communications in time.

Japan would have been the fourth country to land a spacecraft on the moon’s surface, after the former Soviet Union, the US and China. Measuring 11cm by 24cm by 37cm, Omotenashi would have been the smallest craft ever to touch down on the moon.

Jaxa plans to hold a news conference Tuesday. The agency said it will work with other organisations involved to determine what went wrong and how to move forward. It will continue working to restore communications with Omotenashi, hoping the craft can be used to measure radiation and for other experiments.

The project cost millions of dollars, and Jaxa intended for it to help in planning future low-cost lunar exploration missions.

The other Jaxa probe launched Wednesday on the same rocket, Equuleus, is working as intended.