Space Junk: Low Earth orbit is littered with millions of pieces of debris from old satellites, rockets, and even tools dropped by astronauts.
Possible Microscopic Life: In the late 1990s, the discovery of microscopic fossils in a Martian meteorite sparked debate about the possibility of past life on Mars.
Light Show of Cosmic Rays: Astronauts have reported seeing flashes of light in their eyes during spaceflight.
Strange Clouds: Space isn't just a black void. Astronauts have observed a variety of unusual cloud formations in space, including noctilucent clouds, which are Earth's highest-altitude clouds.
Unidentified Space Objects (USOs): While there's no confirmed evidence of extraterrestrial encounters, some astronauts have reported seeing UFOs.
Animal Stowaways: In 2002, tiny tardigrades, also known as water bears, were found to have survived being launched into space on a scientific mission.
Solar Flares and Auroras: Astronauts witness the full fury of the sun firsthand. Solar flares, massive bursts of radiation, can pose a danger to spacecraft and astronauts.
The Beauty and Overview Effect: Perhaps the most profound discovery isn't an object but a perspective shift.