What if you opened fire in space?

The only difference when pulling the trigger on Earth and in space is the shape of the smoke . Peter Schultz, an astronomer at Brown University, said in space, "there would be a huge smoke coming out of the barrel of the gun."

However, shooting in space can also lead to some pretty grotesque scenarios.

Shoot a star

After the shot, the bullet will continue to move in space forever.

Imagine you're floating freely in an intergalactic vacuum, just you, a gun and a bullet. You will have two options. One is that you will think about why you ended up like this. And two is to shoot down a certain star for relief.

With the second option, Newton's Law 3 will cause the reaction from the bullet to hit the gun in the opposite direction with the same magnitude and because you are holding the gun, you will also be affected by it. With very few atoms in space to create resistance, you will slowly drift backwards without even knowing it. If the bullet comes out of the barrel at 1,000 m / s, you will be fired back at a few centimeters / s. The reason is because you have a lot bigger size and volume than bullets.

After the shot, the bullet will continue to move in space forever. "The bullet will never stop, because the universe is expanding faster than the ability of the bullet to hit a large amount of matter" could slow it down, said Matija Cuk, an astronomer at Harvard University. , said. If the universe did not expand, one or two atoms in a cubic centimeter would encounter the bullet in a near-vacuum space that would make it stand still after 10 million light years.

Specifically, the rate of expansion of the universe is about 73 km / s / megaparsec (equivalent to 3 million light years or nearly the average distance between galaxies). According to Cuk's calculations, matter 40 to 50 thousand light years away from the bullet will move away from the bullet at the same speed, so the bullet will never reach that amount of material. In the future, the bullet will only be able to meet atoms nearly 40 thousand light-years away from your muzzle.

By the way, you will also drift in space forever after firing that shot.

Drain all magazine without worrying about sliding the target

In fact, the gun is also carried into space, although not the space between galaxies. For decades, Russian astronauts' survival kits had guns. Until recently, new guns were not included in the kit, but only "a three-part versatile weapon, along with a shovel and a knife," said James Oberg, a space historian. These guns are launched into space for astronauts to use when falling into dangerous areas during the return to Earth. But even so, there is still the possibility of astronauts holding guns shooting miscellaneous before landing.

In the universe, you can theoretically shoot yourself in the back.

So what if the astronaut shot at Jupiter while traveling in space?

This astronaut will be able to shoot freely without looking. According to Robert Flack, a physicist at the University of London, Jupiter's gravity tends to attract the bullet, even though it is fired at the target. "Jupiter is too big, it will catch the bullet and take the planet back in a curve," Flack said.

According to Schultz, if the bullet is fired directly at Jupiter, the planet's gravity will increase the speed of the bullet to about 60 km / s as soon as it enters its atmosphere.

Be careful behind it

Sneaking in the back is a cowardly act. But in space, "you can theoretically shoot yourself in the back," Schultz said.

This can happen when you are in orbit around a planet. Because the objects that orbit around the planet are actually in a free-falling state, you only need a little arrangement to shoot yourself in the back. You will need to shoot the bullet at an appropriate angle so that it can go into orbit and return to the starting point. At the same time, you also need to calculate how far the body will be pushed back, the height changes after the shot.

"The shot must be precise,"  Schultz said.

In fact, the scenario is not as weird as when you hear it. In fact, Schultz says scientists have already tested this phenomenon to study the impact of high speed on objects.

However, given the amount of maths to be dealt with, Cuk suggested that a better way to kill himself in space was to stand at a peak on the Moon. "Sneaking yourself can do it if you stand on a moon crest and shoot at the horizon at about 1,600 m / s." This can work as long as you take into account the level of the moon's concave surface to ensure the shot is fired at an appropriate height.