Mr. Terry hung up the phone and stared into empty space for a little while before he snapped back to reality. He was hurting on the inside, on the one hand, he had lived quite a fulfilling life. Good career, found an excellent wife, obedient and caring children. However, these kids that he was teaching would never get to experience any of these rites of passage that he had enjoyed so much. He quickly tidied up himself and made his way back to the room which was starting to get a bit rowdy.
“Is something the matter Mr. Terry?” Ruby asked with that kind of ignorance only children had.
“No, no, that call was just my Ummm... son... calling to tell me that he was planning something for the entire ship.” He replied while heading back to his desk. “There will be a slight change of plans, we will be learning about Black Holes for the rest of this class. I’m sure you’ve all at least heard of black holes, aside from obvious radiation we also have to worry about black holes the most.”
“Finally! Something interesting! Is it true that they suck everything in? Is it true that nothing will be able to escape from a black hole? Huh? Huh? Huh?” The usually troublemaking and disruptive Bobby asked with a gleaming passion for learning in his eyes.
The sudden change in attitude Bobby just went through pained Mr. Terry infinitely. This child who abhors learning taking an interest in anything was supposed to be a happy occasion, but not this time, thought Mr. Terry.
“Now, now, Bobby. Let’s start with the basics. Black holes, at least the relatively smaller scale ones, are created by a high mass star once it dies and collapses into itself so much that its gravity became so powerful, nothing will be able to escape it once we enter into a certain distance from the black hole.” Mr. Terry started.
“How big is big Mr. Terry? Bigger than our ship?” Bobby asked curiously.
“Of course it’s got to be bigger than our ship, Bobby. Right, Mr. Terry?” Sam scoffed at Bobby’s foolish question.
“No need to be so critical to your classmate Sam. However, high mass stars are considered to be those that are multiple times the size of our very own sun, well our sun that we left behind all those years ago. This ship is the biggest structure you kids know of so I will use this as an example. I have done the math and it seems that this massive ship, which would be unfathomed of in the 21st century, that can sustain over 5 million people can fit into the Earth almost 2,000,000 times.” Mr. Terry said.
“That’s quite a lot,” Bobby said.
“Oh sweet Bobby, I haven’t even begun yet. Our Sun can fit over a million Earth’s into it.”
“My brain is starting to hurt, that is just too many zeroes for my mind to handle,” Bobby said.
“I heard that our sun isn’t even that big compared to the other stars right?” Sam said showcasing her knowledge in this subject.
“That is the case, Sam, any star that is 15 times the mass of our sun is considered high mass. In fact, one of the biggest stars we have ever discovered, VY Canis Majoris, is able to fit over 9 billion of our suns into it. Space is a wonderful place, but it is just as unnerving as it is filled with mysteries,” Mr. Terry chuckled.
“Mr. Terry, what’s the certain distance that you talked about?” Ruby asked.
“There is a certain point of space around a black hole that can be considered a point of no return type of ordeal. Once inside this point that we call the event horizon, nothing will be able to escape the inward pull of the gravity of the black hole, not even light, which is the upper limit for speed in the universe. We call this invisible boundary the event horizon,” Mr. Terry said as he felt the curiosity in the room reach an all-time peak.
“Nothing? Not even us?” Bobby said.
“Nope, unfortunately not. If we could, well I believe we would have reached our destination a few years ago, but we are still not likely to reach it for the next two or three hundred years I’m afraid. If nothing goes awry that is,” Mr. Terry said with a twinge of guilt.
“Then that means we will die if we get trapped inside the event horizon of a black hole then. That. Is. So. Cool.” Bobby continued.
“Now, now, Bobby. Though that is cool as you say, it won’t be that way if we were to actually be trapped in one.” Mr. Terry replied.
“Mr. Terry is there anything we can do if we are trapped inside the event horizon?” Ruby asked with a slight terror showing on her face.
“No, there is absolutely nothing that can be done. The only thing that we can do is wait for the inevitable and enjoy life until the very end. Though sad as it may sound, what else can you possibly do? Panicking won’t help you, crying won’t help either, turning violent only worsens everyone’s last few minutes or hours alive. Don’t you agree children?”
“Yes!” Some shouted out in unison.
“Let me tell you guys about a black star binary. Basically, there are two stars in a binary and one of them turns into a black hole and if the two are close enough, then the black hole will start sucking the other one’s matter in slowly but surely. The best analogy I can think of this for you to understand is that a set of twin sharks are born and one of them turns violent and starts to eat the other one. Terrifying yes, but the best one I can think of.” Mr. Terry said.
“I think my parents told me about this a long time ago, wasn’t there a process called, ummm, something about overflowing?” Sam asked for reassurance.
“You are pretty close Sam, It’s called a Roche Lobe overflow. How it works is that there is gravity on both the black hole and it’s binary or partner I suppose you could say. There is an invisible line separating these two although it’s theorized to look more like the infinity sign but with a slightly distorted midpoint. Well, if matter from the star passes this midpoint, the black hole’s gravity will pull it in ever so slightly and eventually it will fall into the event horizon and eventually fall into the black hole. Any questions?”
“How is it possible for a star to pass this midpoint?” Sam asked.
“Well, there are quite a few ways, but the major one is because the star gets bigger as they get near the end of their lives. Some of them get big enough for it to overflow into the black hole’s gravitational field and eventually falls in. Excellent question. Any one else?” Mr. Terry looked around the room.
“Is this overflow thing how black holes get so big?” Bobby asked seriously for once.
“Well, we don’t understand everything about this matter yet, but that is what many scientists believe. Let me tell you something that will blow all of your minds away. Black holes are some of the densest objects in the universe, as far as we know. For something like Earth, something that you can barely comprehend with your minds, will not be able to become a black hole even if you squished all that mass into a tiny little tennis ball. Nature sure is amazing.” Mr. Terry said in admiration.
“How do you find this out?” Ruby asked.
“Well, without getting into the nitty gritty of it all, it has to deal with the Schwarzschild radius named after a fellow by the name of Karl Schwarzschild who found out this absolutely brilliant equation in 1916. It’s a very complex subject and I will not get into it today. Alright class, how about we take a little break and resume class in 5 or so minutes.”
The students started to mingle in their seats and talk about what they had just learned. At this point, another call from Eli rang from Mr. Terry’s phone. He excused himself and took the call in the previous room.
“Dad, well, I’m sure you know what happens since you are a scientist yourself. We will not be able to avert this catastrophe and save everyone, this is just far too hopeful of our situation.” Eli told his father.
“Unfortunately I know all too well what will happen. Have you and the council made the preparations of what you had described to me earlier?” Mr. Terry asked.
“Yes, actually. We have just finished launching the writing in the stars, and hopefully, it will reach the other ships before they make the same mistake as us.” Eli responded.
“Well, I guess I can look at the bright side and answer a question that we have not been able to answer, what happens inside a black hole. While I may be sad that we will all die, this constant pursuit of answers is the reason that I became a scientist in the first place. I have to go back now, son.” Mr. Terry said.
“Father, I won’t be able to call you anymore after this, but let’s not make this sad. We have calculated the time it will take for us to enter into the place where we will be ripped apart by tidal forces, about an hour or so left. I really have to go now father, thank you for all you have done for me, I just wish I could do the same for you. That does not seem to be possible now.” Eli said nearly breaking into tears.
“Nonsense, my boy. You’re everything that I wanted in a child and so much more. Your mother would have been proud of the one she would call her son. There is nothing to be ashamed of. You have made me such a happy father, and for that I am eternally grateful.” Mr. Terry said while also trying to hold back tears. They said their farewells and soon enough, Mr. Terry got back to his room that was starting to get a little noisy, but first, he had to make sure he was presentable again. Then he went back inside to continue his last lesson.
“Alright class, let’s calm down now. So, there are 3 main classes of black holes: stellar mass, intermediate mass, and supermassive. Stellar mass is classified as ones that have the mass of around 3 to 100 times the mass of our very own sun. While the absolute units that are the supermassive black holes are anything bigger than 100,000 of the mass of our sun. Intermediate-mass black holes are anything in between them, so about 100-100,000 times the mass of our sun.”
“That’s amazing,” Ruby said in awe.
“Quite, but theoretically, there is no limit to how small a black hole can be as long as it is so dense that it is within the Schwarzschild radius. That is to say, if something as small as let’s say the spaceship that we are in, was to be compressed to a size that we wouldn’t even be able to see, then it will be able to become a short-lived black hole. Although, we haven’t been able to find any of these super tiny black holes, which is a pity.” Mr. Terry continued on.