Summary:
- NASA's Perseverance rover is exploring an ancient river delta on Mars, searching for signs that the planet could have supported microbial life in the past.
- The rover is having difficulty drilling into a rock sample that appears to be unusually hard and uncooperative, which is puzzling scientists.
- Understanding the composition and history of this rock could provide valuable insights into the past habitability of Mars and the potential for life to have existed there.