Yes, he's still alive. And as far as I know, he's still a Professor of Theatre Arts at Johns Hopkins University, where he founded the Hopkins University Theatre, "Theater Hopkins," the Old Barn. Astin went to Johns Hopkins majoring in mathematics, I guess to follow in his father's footsteps. (Dr. Allen Varley Astin was director of the National Bureau of Standards.) Which is probably why Astin is a meticulous actor who's able to effectively teach the craft. It is often said that Astin has a "bohemian streak." Depending on who says something like that, you can probably bet that means he knows his own way and isn't shaken by a set-back or two.
Or that whoever said that doesn't get Buddhism.
And anyone who can play the Stage Director in Our Town and Dr. Gangreen in the Killer Tomatoes sequels (yes, with Clooney) and Professor Wickwire on Brisco County and as Linus Pauling can lounge in the stern sheets anytime.
Happy 77th, Professor.