First woman to reach the Challenger Deep

On 7 June 2020, Dr Kathryn Sullivan (USA) became the first woman (and the eighth person overall) to reach the deepest known point in Earth's oceans. The former astronaut and NOAA administrator made the descent in the DSV Limiting Factor, piloted by explorer and retired naval officer Victor Vescovo (USA), who has visited the Challenger Deep more than any other person (eight times as of 26 June 2020). The Challenger Deep is situated at the south-western end of the Mariana Trench, approximately 400 kilometres (250 miles) south-west of Guam, and plunges to c. 10,934 metres (35,872 feet) beneath the surface of the Pacific Ocean.

Sullivan visited the "Eastern Pool" depression at the bottom of the Challenger Deep at c. 10,934 m (35,872 ft) - with a deviation of +/- 3 m at 1-sigma and +/1 6 m at 2-sigma - and spent approximately 1.5 hr exploring the seafloor.

Having also participated in three Space Shuttle missions with NASA between 1984 and 1992, this means that Sullivan is also the first person to visit space and the deepest point on Earth, and has covered the greatest vertical extent by an individual (within Earth's exosphere); those astronauts that took part in missions to the Moon have travelled farther from our planet's surface overall but ventured beyond Earth's atmosphere.

Following the successful dive, back on the surface on board the support vessel Pressure Drop, Sullivan received a direct call from astronauts Chris Cassidy, Doug Hurley and Bob Behnken on the International Space Station offering their congratulations on her achievement.