For a start, it isn't known whether there is even a single sentient species in the Universe - outside of planet Earth, that is. There might be, but this has not been confirmed.
Second, if there are, there is currently no way to know how many there are, or to gather information about them.
Finally, even assuming you can get all the information, you'll have trouble storing that much information on even the largest computer system available today.
You can make 100 billion separate books that has the descriptions of about 10,000 trillion sentient species (100,000 per book) by simply orderly compiling them.
To make 100 billion separate books of all of the information of 10,000 trillion sentient species (100,000 per galaxy) in our universe, you would need to begin by researching each species. Then combine the information using a computer.
Fiction authors have a free hand for what is in their books. However it is not known how many sentient species there are so the author may decide that also.
Yes. There are at least 90 billion trillion or more planets in the observable universe.
It will be impossible when they make all 100 billion reference books that has each all of the descriptions and info on 126,000 sentient species (alien races) of all shapes, sizes, colors, unusual features, etc. in each one of the 100 billion galaxies in the observable universe. Also, it will be 189,000 pages long in each one of them. But for now, it is unknown.
Not even a single alien race has been found so far. However, assuming for the sake of argument that there are, indeed, 10,000 trillion sentient species (100,000 per book), you would first have to gather all the information (where from?), then store it in some computer system. Both seem impossible tasks, at least for the time being.
There are estimated to be around a trillion comets in the Solar System. Assuming that to be "typical" and figuring roughly a billion trillion stars in the universe, that means the number of comets in the universe is probably in the vicinity of a billion trillion trillion (ten to the thirtieth power).
In my opinion, yes. There are at least 10 billion trillion Earth-like planets in the observable universe.
About 100 thousand million billion trillion
approximately 200 billion trillion stars in the universe.
If you counted 1 number per second, it would take 4000 trillion months (320 trillion years) to count all 10 billion trillion stars (100 billion per galaxy) in a fictitious version of our universe.
Yes. There are at least 12,600 trillion intelligent civilizations (i.e. sentient species) in the observable universe (126,000 per galaxy). They come in all shapes, sizes, colors, unusual features, etc. There is also at least 100 billion in-universe reference books of them (excluding non-sentient ones), because in addition to their large portraits, they get a 1 1/2 page detailed description of their species, their histories and what planet and/or moon they're from, which is at least 189,000 pages in length per book. But for now, it is unknown.