I'm not sure specifically who the main characters are without reading the novel, but they could be scientists trying to study the black hole and its effects on Earth.
It's possible that there is a group of adventurers or explorers in the 'Black Hole Earth Novel'. They might be brave enough to venture closer to the black hole to gather information or try to find a way to stop its negative impacts on Earth. Their courage and determination could be central to the plot as they face the unknown and extremely dangerous environment near the black hole.
In the 'black hole novel', the main characters could be a family who lives near a black hole research facility. One of the family members might be a technician at the facility and something goes wrong with the experiments related to the black hole. The family then has to deal with the consequences and try to save the day, while also learning more about the nature of black holes.
As I haven't read 'Black Hole A Novel', it's impossible to accurately name the main characters. But if we think about it, it could be that there are some sort of alien entities associated with the black hole. Maybe they live in some way related to the black hole's energy or gravitational field. Or perhaps there are journalists or writers who are trying to document the story of a black hole discovery and they end up being the main characters as they interact with the scientists and experience the awe and danger of the black hole situation.
Since I haven't read it, I can't say for sure who the main characters are. But they could be scientists, astronauts, or even some fictional beings that have a special connection to the black hole.
Since I haven't read the 'black hole graphic novel', I can't say for sure who the main characters are. But they could be scientists, astronauts, or even some fictional characters created specifically for the story.
In the 'Black Mask Hole Story', if it's a mystery - type story, the main character could be a detective - like figure who wears the black mask to hide their identity while they investigate the strange hole. There might be a local who has some knowledge about the hole and its secrets, and they could be another important character. And perhaps there is a shadowy figure in the background who is somehow connected to the hole and the black mask, either trying to protect its secrets or use it for their own malicious purposes.
I'm not entirely sure as I haven't read all of them. But it's likely there are some characters who are at the center of the action. Maybe there's a fearless explorer type who is trying to uncover the secrets of the black hole pantheon.
One interesting concept could be how the presence of a black hole affects Earth's gravitational field. Maybe it causes extreme tides or disrupts satellite orbits.
Obviously Naruto himself is often involved. He's the main character of the original series, so in fanfiction about Naruto and black holes, he would be at the center of the story. Sasuke might also be involved as his rival and sometimes ally.
I'm not sure as I haven't read it. But it could be soldiers, given the mention of black powder which is often associated with firearms in a military context.
I don't know who the author of 'the black hole novel' is. There are so many novels out there, and without more context, it's difficult to determine the author.