Black Hole Spaghettification

Black Hole Spaghettification

Spaghettification, also known as the “noodle effect,” is the stretching out of an object as it comes into contact with an extreme gravitational field, typically that of a black hole.

Black holes have incredibly powerful tidal forces. The singularities within them contain the most powerful gravitational fields in the known universe. Because of this, objects that venture past their event horizon, or point of no return, cannot escape their pull, whether it be an astronaut, an entire star, or even light itself.

Once an object passes over this threshold, the strong tidal forces stretch it out both vertically and horizontally, similar to a
spaghetti noodle, hence the name “spaghettification.”

Facts about Spaghettification

  • It occurs as a result of the gravitational gradient, a phenomenon where the strength of the gravitational pull on various parts of an object differs depending on the object’s orientation
  • Spaghettification stretches objects vertically and compresses them horizontally
  • A human undergoing spaghettification would likely die in less than a second
  • The process has been observed on large astronomical objects
  • It can occur before or after an object crosses a black hole’s event horizon, depending on the black hole’s size

How does Spaghettification Work?

The simplest way to describe the process is by using a hypothetical astronaut as an example, first discussed by Stephen Hawking in his book, A Brief History of Time.

If an astronaut were to free-fall into a black hole, he or she would be affected by the gravitational gradient, which is the difference in the strength of the gravitational pull depending on the astronaut’s orientation.

If the astronaut were falling feet-first into the black hole, the gravity would be stronger at his or her feet than at their head. This difference in gravitational pull would cause their body to be stretched out.

Additionally, as the astronaut’s body was vertically stretched, their body would also be compressed horizontally. The right side of the body would be pulled towards the left, and the left side pulled towards the right, further stretching them out in a noodle-like fashion.

Would it be painful?

Obviously, the laws of physics would prevent a human from surviving the spaghettification process. Exactly how painful it would be, and at what point they would die depends on the size of the black hole.

For supermassive black holes, since their event horizon is much larger, the point of death would most likely be sometime after crossing the event horizon. However, a person wouldn’t feel any immediate effects
while crossing over the event horizon.

Alternatively, in the case of a smaller black hole with an event horizon much closer to its center, a human would be killed before crossing the event horizon. In both cases, spaghettification would be very quick, occurring in less than a second.

Has it ever been observed?

Spaghettification of an object the size of a human has never been tested, observed, or proven. It has only been hypothesized using mathematical models and calculations of black holes.

However, objects on an astronomical scale have been observed going through this amazing and somewhat terrifying process. In 2018, astronomers observing a pair of colliding galaxies called Arp 299, around 150 million light-years from Earth, captured images of the spaghettification of a star.

Using a combination of radio and infrared telescopes, including the National Science Foundation’s Very Long Baseline Array (VLBA), they witnessed a black hole, 20 million times more massive than the Sun, tearing apart a sizable nearby star. Though this is the first time such an event has been observed, scientists believe they may be a common occurrence throughout the universe.