Wow, I thought he was already dead.
It's cool he lived a long life. 90 is an acomplishment that any human male would like to see. Sadly my father is the oldest male in my family at 56. All my grandfathers and great grandfather died before reaching 50...
The greatest loss when we lose our elders is when we lose all of their knowledge and wisdom, and abilities. Sure we can write things down and document their achievments. But that pals in comparison to actually having the person there to draw off of and learn from. Being my fathers apprentice from the age of 5 on jobs I learned a bit. I can only hope that I can teach my son in the same way (and get free labor) and pass on what little I know.
Did he do the cryogenic thing? Have his brain frozen and stuff in the hopes that in the not to distant future we could clone his body and all that fun stuff. Clarke seemed like the sort.