HOUSTON   -   As the full moon shines in the night sky this weekend, take a moment to revel in its beauty and search for a large, dark plain. The surface feature is Mare Tranquillitatis, or the Sea of Tranquility, where the Apollo 11 mission landed on the afternoon of July 20, 1969. The full moon won’t peak until 6:17 a.m. ET Sunday, but the silvery orb will still appear at its best Saturday, the 55th anniversary of NASA astronauts Neil Armstrong and Buzz Aldrin conducting humankind’s first moonwalk. Now, as NASA and other space agencies plan for a more established human presence on the moon through the Artemis program, it turns out that the Sea of Tranquility may have an unexplored treasure worth revisiting. Scientists have found a subterranean cavity beneath the Sea of Tranquility, and it may provide shelter for future lunar astronauts in the form of a cave. Lunar caves, or underground passages formed by volcanic processes during the moon’s early history, are connected to pits covering the lunar surface. The long, wide cave, found by reviewing archival NASA data, could be used to protect astronauts from harsh radiation and extreme temperature swings as well as provide a new avenue to study lunar rocks. Astronomers have detected an exoplanet with an orbit shaped like a cucumber that may be turning into another type of world. The unusual orbit, which changes temperatures on TIC 241249530 b from a warm summer day to hot enough to melt titanium, may be a sign that the planet is moving closer to its star. Astronomers estimate that in hundreds of millions of years, the planet will only take a few days, rather than six months, to orbit its star and become a hot version of Jupiter. Separately, the European Space Agency plans to send a spacecraft named Ramses to accompany the asteroid Apophis as it makes a safe, close approach of Earth — 10 times nearer than the moon — in April 2029.

The spacecraft could capture quakes and landslides on the space rock as it is affected by Earth’s gravity.