Why NASA astronauts Sunita Williams and Butch Wilmore will experience a splashdown

NASA announced that Wilmore and Williams will depart the ISS on Tuesday, March 18, with the Crew Dragon splashdown scheduled for approximately 5.57 pm EST. The space agency's decision to bring forward the astronauts' return was based on favourable weather conditions.
Have you ever wondered why American astronauts opt for splashdown instead of landing on solid ground? Let's try and find out.

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What is splashdown?

Splashdown is the method of landing a spacecraft by parachute in a body of water, especially by a parachute, in a waterbody, mostly seas and oceans. It was used by American manned spacecraft prior to the Space Shuttle program. It is also possible for the Russian Soyuz spacecraft and Chinese Shenzhou spacecraft to land in water, though this is only a contingency.

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Before a spacecraft, returning to Earth, can perform a safe landing, it needs to slow down. While it is careening back to Earth, a spacecraft has a lot of kinetic energy. Friction with the atmosphere introduces drag, which slows down the spacecraft. The friction converts the spacecraft’s kinetic energy to thermal energy, or heat.

All this heat radiates out into the surrounding air, which gets really, really hot. In the case of SpaceX’s massive Starship rocket, this temperature even reaches 3,000 degrees Fahrenheit (nearly 1,700 degrees Celsius).

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Unfortunately, no matter how quickly this transfer happens, there’s still not enough time during reentry for the vehicle to slow down to a safe enough velocity not to crash. So, the