Ina, the Young Scar
A small, strangely fresh-looking feature on the Moon seems to be far younger than anything around it, if it is young at all.
What was reported
Ina is a small D-shaped depression about 3 km across, first noticed on photographs taken from Apollo 15 in 1971. Its floor is covered in smooth, rounded mounds surrounded by rough, bright ground, unlike almost anywhere else on the Moon.
In 2014 a study counting tiny craters on its surface suggested Ina formed less than 100 million years ago, making it evidence of volcanic activity long after the Moon was thought to have gone quiet.
Explanations offered
Other scientists argue that Ina is billions of years old, and that its unusual surface fools crater counts, perhaps because it's made of porous volcanic foam that absorbs small impacts. Both sides agree it's one of the strangest features on the Moon; a sample from it would settle the question.
- When
- Photographed by Apollo 15 in 1971
- Where
- Ina, Lacus Felicitatis, the Moon
- Witnesses
- Apollo 15 and later lunar orbiters
- Status
- Disputed
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.