First, let me do you a favor.
If you haven’t watched Interstellar, if you couldn’t understand Interstellar or if you don’t like Interstellar, this is not the article for you.
We all believe black holes are the most dangerous entities in the universe. Cold, Dark, and silent giants dispersed all around the universe sucking everything that goes nearby into the dimensions that no scientist can understand. A place where time stops, a place that even light cannot escape from its extreme pull.
So, everyone thought living near a black hole was impossible.
Amidst all this negativity towards black holes, in 2014 Christopher Nolan’s masterpiece interstellar Nolan talked about a different approach towards black holes and the future of human beings. While we desperately trying to save the earth from all this pollution and destruction Nolan talked about leaving the earth. In a world every Sci-fi portrayed a spaceship meeting a black hole as the end of life, Nolan saw an opportunity for the next human civilization. But it’s just a movie, right?
Or…. is it possible?
Before getting into that let’s clear some common misconceptions about black holes. The first one is “we know nothing about black holes”. That is not quite right. Yes, we don’t know what’s beyond the event horizon. But we know what’s before that and most of the physics related to things around a black hole. Another misconception is black holes are completely invisible. Although we can’t see a black hole, we can locate a black hole by many light-emitting objects around a black hole. Easiest is the accretion disk. When particles are attracted towards a black hole, they gain angular momentum and start rotating around it. Due to high gravity, they quickly gain speed and collisions make them hot and they start emitting radiation. Another source is particle jets. And there is hawking radiation. This is the only thing coming from a black hole. a rich high dose of X-Ray radiation. Another misconception is bigger black holes are more dangerous. With a couple of simple equations, we can see for ourselves that larger black holes can make much more stable orbits for planets which is crucial for the existence of life.
So, what are the requirements for life to originate?
The most basic one is, we need a surface, a planet. And this planet needs a stable orbit. A planet also provides a constant source of carbon and minerals. Then an energy source, radiation to some extent. That planet should have an Oxygen and Nitrogen filled atmosphere. A suitable temperature, pressure, and water in liquid form. If a black hole can allow forming a planet with these conditions, we can talk about life.
What are the odds of finding a planet that fulfills all the above requirements?
When you think about it you might feel like it’s extremely thin. But the actual case is quite the opposite. According to French astrophysicist Sean Raymond, there could be around a million habitable planets around a supermassive black hole(SMBH) (theoretically). Furthermore, he says these are in 400 rings with 2500 planets in each ring. Crazy right?
Okay, now we have a million habitable planets. So, what kind of life are we talking about?
Life around a black hole can be discussed in two different ways:
- Origin of life on a planet
- Survival of an already evolved life after migration
First, let’s look at the origin of life around a black hole. As we all know, the Origin of life needs a series of biochemical reactions that take place over a long period. A study done by Harvard University astronomer Manaswi Lingam showed some interesting results related to this area.
Lingam and his team showed that SMBHs are capable of powering UV mediated prebiotic reactions that lead to the synthesis of biomolecular building blocks. And the emission of visible radiations by blackholes opens the possibility of photosynthesis.
But there are problems. These energy sources release a lot of UV and X-ray radiation. Unless these planets have a thick atmosphere evolution of these molecules into life would not be possible. Even if there is a life that will be limited to primitive unicellular life forms. There are bacteria that can withstand high UV amounts by making a biofilm around them. Studies have shown that these habitable zones start around 140 light-years away from Sagittarius A which is a SMBH.
How about the interstellar incident? Can we move to a planet near a black hole and make civilization there?
This is the part where things get a little tricky. Because here, we are not talking about simple organisms. We are talking about complex organisms that need a lot of energy and no native protection against the incoming radiation. So, we need a much bigger black hole; around 163 million solar masses ( even larger than the one that is in the middle of our galaxy which is 4 million solar masses ). Remember what I said earlier, bigger the black hole less deadly. And there is time dilation. Even this is not a huge deal for the origin of life when we talk about migrating humans to a new planet this plays a huge role. A year for a planet near a black hole would feel like thousands of years for us. So, even if we plan to go for a planet near SMBH, all the initial studies that involve going to the planet would take a lot of time. And we need permanent protective measures for protection against all the UV and X-ray radiation. So I think you can understand that humans as a species living near a black hole is almost impossible. Theoretically, it is possible if all things go right. But what are the odds of that?
To summarize everything, there is a considerable chance of the occurrence of life near a black hole. And most probably that life won’t go beyond the unicellular level. But the case in interstellar is not possible. Migrating to a planet near a black hole is a fight with radiation, time dilation, and finding a rare one-of-a-kind black hole.
WHY?
When I was writing the last paragraph, a question popped into my mind that almost made me clear the whole article I wrote. That was why we are interested in these highly theoretical and improbable things. What’s the reason?
To be honest of all the things we discussed in this article, this is the hardest to answer. Or at least this was the hardest question to answer a few years back. But one man proved that there are benefits to space exploration in recent years. He is none other than Elon Musk. Here, Logic is simple. A man simply doesn’t spend billions of his money for space exploration if there is no benefit out of it. So here is how Mr. Musk Explains why we need this space exploration.
“When I was in college there were three areas that I thought of what’s really going to affect the future of Humanity in a significant way. They were the Internet, the transition to sustainable energy, and the third was the extension of life beyond Earth and becoming a multi-planetary.
If you zoom out and look at a long enough period of the four-billion-year history of Earth and the evolution of life itself, then there are only about half a dozen or so major milestones. So you know here we are and it’s sort of the first time in the four billion year history of Earth that life has been able to go beyond Earth. And that window may be open for a long time but something may happen that closes that window and prevents us from extending life beyond Earth and that risks the extension of life or at least consciousness as we know it. That would be a terrible thing. Life is a terrible thing to waste.”
Written by: Kalana Bandara
- McKay, C. P. (2014). Requirements and limits for life in the context of exoplanets. Proceedings of the National Academy of Sciences, 111(35), 12628–12633.
- Could a habitable planet orbit a black hole?
- Bakala, P., Dočekal, J., & Turoňová, Z. (2020). Habitable zones around almost extremely spinning black holes (black sun revisited). The Astrophysical Journal, 889(1), 41.
