NASA has released the Artemis II crew’s handwritten notes from their lunar flyby, including observations of mysterious flashes on the Moon.

The agency’s Preliminary Lunar Science Report, published on October 8, confirms the astronauts saw five extremely faint “pinprick” bursts of light on the lunar surface from 46,000 miles away. Scientists ruled out spacecraft reflections and cosmic rays before concluding the flashes were caused by rocky fragments striking the Moon.

The crew also experienced a 54-minute total solar eclipse while passing behind the Moon’s far side, creating ideal dark conditions for the observations.

Pilot Victor Glover described the lunar terminator as “islands of light” with valleys like black holes. The notes by Reid Wiseman, Glover and Jeremy Hansen mark the first crewed lunar science observations in over 50 years.

Artemis II was the first crewed lunar mission in more than five decades, flying four astronauts around the Moon without landing. The science report’s findings will feed into planning for Artemis III, which aims to return astronauts to the surface.