After reaching high altitudes in 1984 being the first female American to journey in outer space, Kathy Sullivan has now reached rock bottom. This is after she has also become the first woman to go to the lowest depths of Earth reaching the Challenger Deep.

In a report by The Times of the UK, it seemed that Sullivan's historical walk in outer space on the 11th of October in 1984 was not enough for her and decided to dive 36,000 feet into the depths of the Pacific Ocean. In her journey about 6.8 miles under the sea, she was aboard Limited Factor, a submersible.

Last Saturday, Sullivan updated her Facebook status and informed everyone that she was able to complete the historic dive into the lowest point of Earth and back.

According to the New York Times, 68-year-old Sullivan was accompanied by the Victor Velasco, the 54-year-old pilot of the vessel. The former astronaut and the retired US Navy officer celebrated their successful feat by giving the International Space Station a call after they returned safely from their expedition.

Sullivan is only the eight-person in the world who is able to accomplish such feat and reach the Challenger Deep. According to her, being a hybrid astronaut and oceanographer is a moment that is only done once in a lifetime.

Read also: Dinosaur's Final Meal: 110 Million Years Old Dinosaur Stomach Contents Unveiled

Challenger Deep is a trench within Mariana's Trench which is about a mile deeper down the ocean compared to the altitude of the planet's highest peak, Mount Everest. The said deep belongs to the hadal zone, which got its name from Greek mythology's underworld which is the domain of Hades. The place has also a very high water pressure which is often compared to the pressure of 100 elephants standing in the head of a person. Aside from this, the place's temperature is very low and since it is deep down in the trench there is no light source.

In 1960, Lt. Don Walsh of the Us Nave and Jacques Piccard who is an oceanographer from Switzerland became the first people to reach the deep.

Before Sullivan, the latest to visit the deep is an underwater explorer and the director of the classic film "Titanic", James Cameron. Cameron went into the depths of Mariana's Trench in 2019 in the vessel Deepsea Challenger.

According to CNet, Sullivan's Dive aboard the Limiting Factor which Triton Submarines of Florida manufactured was a collaborative effort with Caladan Oceanic and Eyos Expeditions.

Eyos Expedition's Rob McCallum said that Challenger Deep is one if not the most exclusive spot on the planet, He also said that more people have traveled to outer space and the moon than those who have dived into the bottom of the ocean.

During her spacewalk, Sullivan traveled to space aboard the space shuttle called the Challenger. It can be noted that both the spacecraft that brought her to outer space and the trench in the Pacific that she dove into is named after the Royal Navy ship which was first to record the depth of the planet's lowest point in 1875. The ship was known as HMS Challenger.

Related article: $1 Million Rocky Mountain Treasure Found After Decades