You should check out Richard Feynman. He wrote several books on theoretical physics and they are very interesting. He is one of the top Theoretical Physicist of our time.

I read the book from Hawkings about the nature of time ( A Brief History of Time). It is a bit simplistic since he wanted to expand readership but it is a great book and it is not long and boring. The only hard part is visualizing the Universe with the 4th dimension, space/time.

Thinking about the question and reading the responses, I realize I never was a hero worshiper... oh, in the 50's maybe Mickey Mantle, The Mick !
Most of gentlemen listed below I admire as well, (those that i'm familiar with), along with Richard Dawkins and so many women of science, Marie Curie, on n on on...
Today if I had heroes they'd be Barack Obama, Elizabeth Warren, Bernie Sanders, Tulsi Gabbard and a few others.

Jacob Bronowski, James Burke, Phillip Morrison. The first two, Historians of science. The last an actual scientist. All have had many books and/or TV series.

My life would have never been the same without these men. All before Sagan became famous as He did. The first biography I ever read was about Louis Agassiz, When I was in the 3rd or 4th Grade.

Sagan is a great choice. I've read Cosmos, Demon Haunted World and Billiions and Billions. I love his writing style.

I think Neil deGrasse-Tyson is another amazing personality. He was a great successor to Carl Sagan as the host of Cosmos. I enjoy his interviews and presentations that are available on YouTube too.

Sam Harris, Lawrence Krause, Neil Degrasse Tyson. I think they have all contributed to the way I look at the world.

So, he's a businessman, not a scientist, but I really admire Elon Musk for recognizing the coming energy crisis, and doing everything he can to help us transition from a fossil fuel based economy to a lean, green, solar machine. Science can save us, but without the will to use the tech that we already have, there's not going to be much left to save.

Richard Feynman called em on their bullshit when Challenger blew up. Tesla was a man out of time. There are so many (and so few) - as Newton said "I stand on the shoulders of giants", so hard to pick just one. Jules Verne was not a scientist, but a visionary

Like many of my generation I found Dr. Carl Sagan to be an inspiration. His PBS show "Cosmos" affected me deeply. And today I regularly test what others tell me by using Sagan Standard (Extraordinary claims require extraordinary evidence".)

It was Sagan for me, Cosmos was hittign the airwaves when my daughter was born, I would sit with her in teh maternity wing and watch it while she was asleep. We went to live in teh bush after my son was born, I stopped watching TV, but we took tapes of Cosmos and Life on Earth with us.

I admire Johah Saulk, who developed the Polio vaccine. Wha tis even more admirable is that rather than make a fortuen off of it, he put it out in the public domain for everyone's benefit.

Last I checked, one of thre strains of hte disease has been completely vanquished. The last pockets are in thrid world Asian countries, although there is the occasional outbreak elsewhere due to how easy it is for peopel to travel.