BLACK HOLES: A Dark Dive

Without a doubt, the most intriguing celestial bodies in the universe are black holes. A black hole is a region in space where gravity is so strong that nothing can escape from it, not even light hence the name "black". Gravity is said to be just under the surface of a black hole because of how dense its interior is.(Black Holes, NASA)

According to Einstein's general theory of relativity, a black hole may develop when spacetime is deformed by a sufficiently condensed mass. (Wikipedia). Blackholes are formed when massive stars undergo a supernova explosion at the end of their life cycle. When a star runs out of its nuclear fuel, it can no longer withstand the force of gravity. The core of the star collapses, forming a black hole. This black hole grows as it absorbs its surrounding mass.

The black hole structure simply consists of the outer and inner event horizon and the singularity. The event horizon generally marks the boundary beyond which nothing can affect the observer, the velocity to escape is equal to the speed of light and as general relativity theory suggests nothing can outrun or even compete with the speed of light so there is no escape. The center point is called the singularity a point where there is infinite density formed because of the mass being absorbed. (Event Horizon, Britannica)

So how have the knowledge and understanding of Black holes developed over time? Let's take a step back to 1971, the first black hole known as Cygnus X-1, was identified by researchers Paul Murdin and Louise Webster. When a rocket was launched into space it detected enormous amounts of X-rays which was impossible for an independent star to produce.

“Cygnus X-1 was the subject of a bet between Kip Thorne, who argued for a black hole, and Stephen Hawking, who argued against it. The bet wasn’t settled in Thorne’s favor until 1990” (Sky at Night, BBC)

The first image of a black hole—or rather, its shadow—was taken in 2019 where a light being bent around the supermassive black hole at the center of M87 was recorded by a global network of radio telescopes. The presence of these (primarily) unseen giants is now undeniable.

You may be wondering what exists beyond a black hole a portal, a parallel universe, or a different world however the reality is far from that as NASA stated in an article:

 “General relativity predicts that the very center of a black hole contains a point where matter is crushed to infinite density. It’s the final destination for anything falling into the event horizon”

 The corona of a supermassive black hole appears as pale, conical swirls above the accretion disk in this illustration

. NASA/Aurore Simonnet (Sonoma State Univ.)

As we have seen the structure and properties of a black hole it is concluded by science that extreme spacetime distortions brought forth by the strong gravitational pull inside a black hole create an environment that is both strange and intriguing, contradicting common sense. Any incident engulfing materials like rockets, satellites, and other matter has sent no message that could be a clue for further development, hence the mystery of black holes is still not fully explored. As stated in an article by Space:

"Falling through an event horizon is passing beyond the veil — once someone falls past it, nobody could ever send a message back," he said. "They'd be ripped to pieces by the enormous gravity” (where do black holes lead, space)

Glossary:

• Core: Central region of a star's nuclear fusion.

• Deformation: Warping by massive gravitational forces.

• Nuclear fuel: Energy for stellar fusion reactions.

• Portal: Passage through spacetime's mysterious veil.

• Spacetime: Blend of space and time continuum.

• Supernova explosion: Massive stellar energy release event.

• Theory of relativity: the laws of physics are the same for all observers in uniform motion and describe how gravity affects the fabric of spacetime.

• X-rays: High-energy radiation from astronomical objects.

References

1. https://science.nasa.gov/universe/black-holes/anatomy/, NASA, anatomy of a black hole

2. https://science.nasa.gov/universe/black-holes/,  NASA, Black hole basics

3. https://www.skyatnightmagazine.com/space-science/black-holes-first-discovered, “sky at night magazine” by BBC by Colin Stuart, February 28, 2024

4. https://cosmosmagazine.com/space/astrophysics/9-coolest-stories-about-black-holes-from-2021/,  COSMOS Credit: DESY, Science Communication Lab, December 21, 2021

5. https://www.britannica.com/topic/event-horizon-black-hole,Britannica Written and fact-checked by The Editors of Encyclopaedia Britannica, Sep 7, 2024

6. https://www.space.com/where-do-black-holes-lead.html,Space, Where do black holes lead to? By David Crookes, Daisy Dobrijev

Written By: Minahil Malik