![](http://www.ecns.cn/hd/2024/07/18/869701935ed848209e0d0523e149a055.jpg)
Photo released on July 15 shows the Mare Tranquillitatis pit as seen by NASA's Lunar Reconnaissance Orbiter. (Photo/VCG)
Researchers have found evidence for a substantial underground cave on the moon that is accessible from the surface, making the spot a prime location to build a future lunar base.
![](http://www.ecns.cn/hd/2024/07/18/88a250a8f54d445193e6436db767ffc9.jpg)
Photo released on July 15 shows the Mare Tranquillitatis pit as seen by NASA's Lunar Reconnaissance Orbiter. (Photo/VCG)