Describe in about 30-40 wordsthe peculiarities of the diary in the lesson?

I would say the main peculiarity of the diary in The Diary of a Space Traveler is the fact that it came back to earth without its owner. It was written by Professor Shonku who built a rocket to go to Mars and he did, but his diary was found on earth even though he wasn't.

faze apex of course.

i think the life is invaluable.

you can also say immeasurable.