A rock from Mars collected by a Japanese Antarctic research expedition is set to be exhibited at the 2025 World Exposition to be held in Osaka, according to government sources.

The rock is the world's biggest sample of a meteorite from Mars and holds significance as it indicates that there once existed water on the planet. The government hopes to make it a key exhibit item at the Expo.

The government is also mulling the display of sand retrieved by the Hayabusa2 explorer from the asteroid Ryugu in 2020. It plans to set up a booth exploring the origins of the universe and life in line with the Expo theme "Designing Future Society for Our Lives."

The Mars rock was discovered by the Antarctic research expedition in 2000. It is about the size of a rugby ball, with a width of 29 centimeters, depth of 22 centimeters and height of 16 centimeters. It is stored at the National Institute of Polar Research in Tachikawa, Tokyo.

In the last Osaka Expo in 1970, a long line of visitors formed for an exhibit of a moon rock, retrieved in the Apollo 12 lunar mission, at the U.S. pavilion.