Outer space can be very scary for many different reasons. In general, however, when a human being goes into space, they are kept within some type of vehicle or space station. Even when they go outside the space station to complete some type of work, it is a priority to keep the astronaut tethered securely in place so that they don’t float away.

Rarely, however, it is necessary for an astronaut to go out into space with no tether at all. It has happened just four times in the history of space exploration, and the pictures and videos of the events are widely considered to be among the most terrifying to exist.

An untethered space walk is scary for a number of reasons. Visually, they make most people uneasy because the astronaut is simply floating out in space, attached to nothing. When you see it, you can’t help but wonder what would happen if they were unable to maneuver themselves back onto the shuttle or space station. Floating out in space until you run out of air sounds like something out of a nightmare.

It is also terrifying because of how dangerous it can be. If the astronaut makes a mistake or their equipment fails, there may be no way to recover them in time.

On February 7, 1984, astronaut Bruce McCandless II became the first person to ever experience this. The video of him floating away from the space shuttle Challenger is famous, often described as the most terrifying space video ever.

Just a few days later on February 9th, astronaut Bob Stewart joined him on an untethered trip outside of the shuttle. Just to make this a little scarier, it is important to remember that were moving at almost 28,900 kilometers per hour (18,000 miles per hour) while in orbit high above the Earth.

Later in the year, astronauts Dale Gardner and Joseph Allen both had to fly untethered through space. This time they were doing it in order to recover two satellites that were placed into incorrect orbits after a rocket failure. NASA decided that having these astronauts get into manned maneuvering units (MMUs) to retrieve the satellites was the best option. Fortunately, they were able to complete the mission successfully, with astronaut Anna Fisher operating a remote manipulator system for support.

You can see this activity take place in a video from NASA:

NASA explained what happened during this mission:

“After Hauck and Walker piloted Discovery to within 35 feet of Palapa, Allen and Gardner exited the airlock to begin the spacewalk portion of the satellite capture. Allen donned the MMU mounted on the side wall of the cargo bay, attached the stinger to its arms, and flew out to Palapa. Once there, he inserted the stinger into the satellite’s Apogee Kick Motor bell and using the MMU’s attitude control system stopped Palapa’s spin.

Fisher then steered the RMS to capture a grapple fixture mounted on the stinger between Allen and the satellite. She then maneuvered them over the payload bay where Gardner waited to remove its omnidirectional antenna and install the bridge structure. However, Gardner could not attach the ABS to the satellite due to an unexpected clearance issue on the satellite. Using a backup plan, Allen undocked from the stinger, leaving it attached to the satellite as well as the RMS, and stowed the MMU in the payload bay. With Allen now holding the satellite by its antenna, Gardner attached an adaptor to the bottom end of the satellite to secure it in its cradle in the payload bay.”

It can never be said that astronauts are not among the most brave people in (or above) the world.

Personally, I will gladly stay down here on Earth with my feet on the ground.

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