How to Return to the Spacecraft after Astronaut Drifts Away in Space?

Safety measures and teamwork in space travel.

First of all, the spacesuit is equipped with dual-hook safety ropes. To climb from point A to point B on the spacecraft, the procedure is to unlock one of the safety ropes, hook it onto point B, cross over, and then hook the A point safety rope onto point B. This ensures that there is always one safety rope attached to the spacecraft railing. If you lose even this, it only means that you didn’t follow the instructions and generally they won’t even let you go up there.

Of course, you may argue that the hook itself may be faulty, or that some micro meteorites have punctured the safety rope or something. Well, let’s assume you survive in such a situation. You don’t need to panic because there is a saying from Muhammad: “If the mountain won’t come to Muhammad, then Muhammad must go to the mountain.”

It’s the same in space. As long as you don’t get ejected, it’s usually just a deviation of a few meters per second in relative velocity. It’s true that you don’t have any propulsion on your own, but the spacecraft does. If you don’t go towards the spacecraft, the spacecraft will come towards you. RCS, activate!

Like this, you watch as a few spots appear on the surface of the spacecraft, and then this tens of tons (or even hundreds of tons) giant gradually glides towards you. Just reach out your hand and you can grab onto the railings all over the spacecraft, along with your terrified pale-faced teammate, and the unavoidable scolding after returning to the cabin.

But so what? As long as you survive, that’s all that matters.

Outcomes of Astronauts' Failure to Secure Themselves Outside Spaceship

Once an astronaut fails to hold on and falls into space when exiting the spacecraft, their fate will be extremely tragic. Let’s take a look at two real cases.

Case 1

On March 18, 1965, Soviet astronaut Leonov boarded the “Voskhod 2” spacecraft and entered space, successfully completing the first-ever spacewalk in human history. This laid the foundation for human space exploration. However, it was during this spacewalk that Leonov almost didn’t make it back.

At that time, Leonov was one of the first group of astronauts selected, with outstanding personal abilities. Originally, the spacewalk was scheduled for 1967, but due to increasing competition between the US and the Soviet Union, the plan was advanced by two years. Despite many preparations being incomplete, Leonov was pushed up to carry out the mission.

Before preparing to exit the spacecraft, Leonov first went to the airtight chamber to breathe oxygen. He needed to inhale a large amount of pure oxygen to reduce the nitrogen content in his blood. After an hour of preparation, Leonov finally opened the hatch and slowly floated out of the spacecraft into space.

As Leonov floated further and further away, he eventually stopped at a distance of 5.3 meters from the spacecraft. This was the length of the safety cord attached to him, with one end locked to the spacecraft and the other locked to Leonov, preventing him from accidentally falling into space.

After floating in space for a while, Leonov then stayed on top of the spacecraft for a few minutes. Just as he was preparing to return to the spacecraft, an unexpected accident occurred.

At that time, there were some defects in the design of the spacesuit. It swelled up like a balloon, almost about to burst, whether it was due to excessive pressure inside or some other malfunction.

If the spacesuit burst open, Leonov would be exposed to the vacuum of space. Within a minute, his body would boil, and he would suffocate to death. Fortunately, the spacesuit didn’t burst open, it just swelled up like a balloon.

The spacecraft’s hatch was small, and Leonov could barely squeeze back in. However, after the spacesuit swelled up, Leonov couldn’t get in no matter how hard he tried. He was stuck outside.

If a solution couldn’t be found, he would be forever stranded in space. At that moment, Leonov was extremely nervous, with his heartbeats reaching 190 per minute and cold sweat all over his body.

Fortunately, Leonov was a well-trained pilot and an outstanding astronaut. Even though he was extremely nervous, when faced with this sudden situation, Leonov found a risky solution: he opened the exhaust valve of the spacesuit, releasing all the gas inside, and then quickly managed to make his way back into the spacecraft.

At that time, the gas released from the spacesuit was primarily oxygen. If he hadn’t seized the opportunity to get back into the spacecraft, he would have suffocated due to lack of oxygen and remained in space forever.

Case 2

On September 25, 2008, the manned spacecraft Shenzhou 7 was successfully launched. The next day, Shenzhou 7 completed its orbit change and entered a circular orbit at an altitude of 343 kilometers. The spacewalk mission was about to begin.

On September 27, after sufficient rest, astronauts Zhai Zhigang and Liu Boming prepared for the spacewalk. They arrived at the spacecraft hatch and tried to open it together, but to their surprise, the hatch didn’t budge.

At that moment, Zhai and Liu felt a tightness in their hearts. They looked at each other, ready to give it another try. However, even if they exerted all their strength, they could only open the hatch a small crack. Before they could react, the hatch closed again.

Could it be that the mission was already over before it even began?

As the best astronauts in China, Zhai and Liu didn’t want the “China’s first spacewalk mission” to fail. They decided to take a break to regain their strength and then make another attempt.

After a short rest, Zhai reached out his hand towards the hatch again, while Liu took out a lever. Yes, the most advanced spacecraft in China was opened by a lever.

It was later discovered that the hatch couldn’t open because of a pressure issue. The air inside the cabin wasn’t completely released, resulting in high pressure that prevented the hatch from opening. Regardless of the situation, Liu and Zhai solved the problem using the lever. They opened the hatch.

However, just at the moment the hatch opened, a piercing fire alarm sounded. The instrument panel showed a fire in the orbital module.

A spacecraft on fire isn’t a joke. Once it explodes, both the astronauts and the spacecraft would be destroyed, forever trapped in space.

In an instant, the hearts of the three astronauts were gripped with tension. Jing Haipeng quickly checked the situation in the cabin, hoping to resolve the problem as soon as possible. Liu Boming and Zhai Zhigang were prepared to risk their lives to defend the brief glory of the mission.

Liu Boming said, “There’s no time for us to worry about the fire anymore. Let’s just focus on completing the mission.”

Zhai Zhigang responded succinctly with just two words, “Understood!”

Accompanied by the piercing fire alarm, Liu Boming and Zhai Zhigang successfully exited the spacecraft. They waved the Chinese national flag in their hands, greeting all the people of the world.

The successful spacewalk by Liu Boming and Zhai Zhigang marked the completion of China’s first spacewalk mission, making China a country capable of independently conducting spacewalks.

After completing the spacewalk mission, Liu Boming and Zhai Zhigang returned to the spacecraft. After a careful inspection, they discovered that there was no fire in the orbital module. It was a false alarm.

Everyone let out a sigh of relief. If the spacecraft had actually caught fire or any unexpected accidents had occurred, these three heroic astronauts would have been forever trapped in space.

The two real cases above are the actual experiences of astronauts. They almost became permanent residents of space. Now, let’s return to the topic at hand - what happens if astronauts fail to hold on and detach from the spacecraft?

Under normal circumstances, it is very difficult for an astronaut to detach from the spacecraft.

When an astronaut exits the spacecraft, they are always attached to a safety tether specially designed to be uncuttable even with a knife. The two ends of this safety tether are connected to both the spacecraft and the astronaut, firmly keeping them connected.

With the protection of the safety tether, an astronaut will never disconnect from the spacecraft. When they want to return, they simply need to hold onto the safety tether and drift back slowly, which is very convenient.

Unless an astronaut is too excited and exits without securing the safety tether, there is a possibility of detaching from the spacecraft. In this situation, as long as they are not too far from the spacecraft, there are still some self-rescue methods.

1. Jetpack

Each astronaut carries a jetpack on their back when exiting the spacecraft. As the name suggests, this backpack generates propulsion through jetting, allowing astronauts to maneuver in space.

The space jetpack has numerous jet nozzles, providing 360-degree coverage. It can fly in any direction, with a maximum speed of 48 kilometers per hour. If an astronaut is not far from the spacecraft, using the jetpack gives them a good chance to return.

2. Deflating the spacesuit

Although the jetpack is sophisticated, it can still malfunction. If it fails to function properly, astronauts have another unconventional solution, which is to release the oxygen inside their spacesuits.

By releasing the oxygen, they can generate propulsion and approach the spacecraft. However, this method is only feasible if there is enough oxygen and they are close enough to the spacecraft.

What happens if an astronaut detaches from the spacecraft and cannot return?

Detaching from the spacecraft means losing all supplies. There would be no water, no food, and the oxygen inside the spacesuit would only last for about 8 hours, at most 16 hours. After 16 hours, the astronaut would suffocate and perish.

Protected by the spacesuit and affected by the space environment, an astronaut’s body wouldn’t be harmed.

Space is a unique environment. In places with the presence of the sun, the temperature is high, causing the astronaut’s body to dehydrate, becoming a mummified corpse that doesn’t decay. In places without the sun, the temperature is extremely low, freezing the astronaut’s body, also preventing decay.

In simple terms, regardless of the situation, an astronaut’s body won’t decay. They would continue to float in space, possibly returning to Earth or flying into deep space. But no matter which direction they fly in, they will all face the same fate of being reduced to ashes.

In Conclusion

Space is dangerous, and the space environment is harsh. However, there are countless heroic astronauts who continuously engage in spacewalks, aiming to help humanity conquer the universe. They are heroes, worthy of respect!

Throwing Tools in Space

According to a story about an American astronaut:

While repairing the space station, the astronaut wanted to return to the module, but suddenly the rope came loose and the person started drifting away.

In a moment of desperation, the astronaut threw the wrench in his hand in the opposite direction, causing them to slowly move towards the spacecraft.

The astronaut had several other tools in their hand, so they continued throwing them…

In the end, they made it back to the spacecraft.

Note: When I first read this story, the astronaut had a name, but over time, I have forgotten.

Spacewalk Procedures and Precautions (航天员出舱程序和预防措施)

After the astronaut leaves the spacecraft, at most one of the two safety ropes can be disconnected at the same time. Setting aside the muscle memory already developed through ground simulations, the most important aspect is that every step (movement) has been prearranged and must undergo confirmation 2-3 times (by oneself, teammates, and ground command).

Generally speaking, astronauts working outside the spacecraft usually secure themselves with a foot restraint. Whenever they need to move, they must confirm the status of their safety ropes three times. If it’s not apparent from the video received on the ground that the astronaut forgot to attach the safety rope, their teammate didn’t notice, and they themselves forgot and moved without being attached, it wouldn’t be much of a problem.

This is because astronauts usually move by clinging to the spacecraft wall or standing on the robotic arm. If they have been moving for five or six minutes without anyone noticing that they haven’t attached their safety rope, the probability is extremely low.

Once they start “floating,” they will be able to intuitively sense it and can grab onto the handrails on the spacecraft wall.

If it really happens that they become distracted by the equipment on their spacesuit and inadvertently float away without noticing, their teammate would generally notice it in a timely manner. Their teammate can just grab them.

If both of them become so distracted that they don’t notice one of them floating away, it would be beyond reach. They would first throw a rope, and if they can’t grab onto it, they would use the robotic arm. If the robotic arm can’t reach, they would send someone in the Extravehicular Mobility Unit (EMU) to catch them. If even that is not possible, they would manipulate the space station. If the space station can’t reach, they would directly separate a Shenzhou spacecraft to catch them.

They would then wait to be disciplined upon returning.

Safety Measures for Spacewalks

Answer: The main method of connecting the astronauts to the spacecraft during a spacewalk is with a safety tether. Without the safety tether, there is a certain degree of danger for astronauts floating away from the spacecraft.

A spacewalk refers to when astronauts venture outside the spacecraft for equipment repairs or scientific experiments. Due to the lack of the spacecraft’s solid outer shell for protection, spacewalks are inherently risky. One of the dangers is that astronauts may be unable to return to the spacecraft once they detach from it. However, there are certain methods to address this, such as the following:

Safety tether connection

In general, during a spacewalk, astronauts connect themselves to the spacecraft using a safety tether, which allows them to return to the spacecraft when they lose their footing.

In the early days of spacesuit technology, the safety tether used during spacewalks was generally made in the form of an umbilical cord, which provided a continuous source of life support for the astronauts. Nowadays, spacewalk suits do not typically adopt this method because the umbilical cord has limitations in terms of distance.

Thrust-assisted spacesuit

Modern spacewalk suits are equipped with independent life support systems that provide astronauts with oxygen, pressure, temperature, and even propulsion.

For example, the spacewalk suits used on American space shuttles are equipped with 24 nitrogen thrusters, allowing astronauts to easily control their own posture and safely return to the spacecraft even when completely detached from it. However, the amount of nitrogen in the thrusters is limited. If an astronaut drifts too far away from the spacecraft’s orbit, it may become impossible to return.

In such a situation, astronauts must try their best to discard any objects they can and then use the recoil force to push themselves towards the spacecraft. As a last resort, they may have to release some of the gas used for the breathing system, just like the actions depicted in the movie “The Martian” by the protagonist.

How to Return to the Spacecraft After Drifting Away in Space?

How to Return to the Spacecraft if an Astronaut Accidentally Drifts Away in Space?

If an astronaut accidentally drifts away from the spacecraft while they are outside the cabin in space, they need to follow specific procedures to safely return. This situation, known as an untethered spacewalk, requires immediate action to ensure the astronaut’s survival and their reunion with the spacecraft.

  1. Stay Calm: It is crucial for the astronaut to remain calm and composed, as panic can further complicate the situation.

  2. Assess the Situation: The astronaut needs to evaluate their distance from the spacecraft and determine if they can reach it by using propulsion devices or other means of propulsion.

  3. Activate Rescue System: If the astronaut cannot reach the spacecraft on their own, they should activate the rescue system provided in their spacesuit. This system is designed to generate a thrust force that can bring them closer to the spacecraft.

  4. Communicate with Mission Control: Simultaneously, the astronaut should establish communication with the Mission Control Center on Earth. They should inform the control center about the situation and receive guidance and assistance.

  5. Follow Mission Control’s Instructions: The astronaut must follow the instructions provided by the Mission Control Center precisely. Mission Control will guide them on the necessary steps to return safely to the spacecraft.

  6. Use Propulsion Devices: If available, the astronaut should utilize propulsion devices like hand-held jets or space tethers to maneuver back to the spacecraft. These tools can generate thrust and aid the astronaut in regaining proximity to the spaceship.

  7. Monitor Oxygen Levels: During the return process, the astronaut should closely monitor their oxygen levels and ensure they have an adequate supply. In case of any depletion or malfunction, the astronaut must inform the Mission Control Center immediately.

  8. Utilize Any Nearby Structures: If in proximity to other structures such as satellites or space stations, the astronaut may consider using them as temporary shelters or platforms to wait until further assistance arrives.

  9. Emergency Return Vehicle: In extreme cases where the astronaut cannot reach the spacecraft or any suitable structure, they may need to deploy an emergency return vehicle. This vehicle serves as a lifeboat and can provide a safe passage back to the spacecraft.

Remember, the utmost priority is the immediate and safe retrieval of the astronaut. Therefore, quick communication with Mission Control and adherence to their instructions is crucial in such situations.

Throw helmet backwards for chance to float back to spaceship.

Simple, you know about the conservation of momentum, right?

Take off your helmet and throw it forcefully in the opposite direction.

You have a chance of floating back towards the spaceship.

Returning to Earth or another space station without equipment would be difficult.

Oxygen probably only lasts about 30 minutes, and there probably isn’t much left because some has already been used earlier. It would be extremely dangerous for the astronaut to float away from the spacecraft. Either the mother ship needs to launch an oxygen cylinder to him, or he needs to use a jetpack to return to the mother ship. Of course, the astronaut is currently secured by a safety rope, so even if he drifts away, he can use that thin steel wire rope to pull himself back to the spacecraft.

If the mother ship explodes or loses control and becomes uninhabitable, the astronaut can still try to find a way to return to Earth or another space station. This would require some jet propulsion equipment, parachutes, and so on. However, many astronauts do not possess these resources, so it’s really unclear what they would do in that case.

Throwing things in the opposite direction of the spacecraft obeys the law of conservation of momentum.

Conservation of Momentum Law: Just Throw Stuff in the Opposite Direction of the Spaceship

The law of conservation of momentum states that by throwing objects in the opposite direction of the spaceship, momentum can be conserved.