Question: Why choose this job instead of being a writer?

Well, justasickmonster …difficult to say. Probably it’s because I think you have to live an interesting life to write interesting things.
My job is allowing me to do a lot of cool things (like travelling, meeting with interesting people from all over the world, posing questions about our Planet and trying to find answers..) and at night, there is always time to write.
Maybe I am wrong, and of you want to write, you should write at 100%, however, I personally feel better to have “another job” and keep writing as an hobby. In a future, who knows? I might change my mind and turn into a writer of scientific novels! Better to know a bit of physics, then, right? 😉