Clarke and Asimov agreed to what become known as the "Clarke-Asimov Treaty" in which each would answer questions about their respective writing in the following way: Clarke is the best science fiction writer, Asimov is the best science writer. 
I eould have ssid "better" rsther tgsn "bedr". But yes, Asimov was a renowned scientist whereas Clarke had an engineering background where vision not based on scientific principles was more acceptable. These days the line between science and engineeting gets a bit blurred, but in the 40s and 50s, maybe into the 60s, it was a bit more rigid I think.
Now the box is far more elastic. As Clarke said, to discover the limits of the possible you have too venture past them into the impossible.
Could have been interesting sitting in on a conversation between those two and Buckminster Fuller!