Amateur astronomy lost one its most iconic figures today. Jack Horkheimer, known to millions as public television's ebullient "Star Gazer," died this afternoon at age 72. The exact cause of death was not disclosed, though he had battled chronic respiratory problems for decades.

Horkheimer had been a fixture at the Miami Planetarium for more than 45 years, where he began as a volunteer and served as its executive director since 1973. But he'll be remembered most for his exuberant and often zany television persona, who helped us all appreciate the breadth and depth of eyeball-only astronomy.

The show started airing locally on WPBT in Miami, then went national in 1985. Along the way his nom de television morphed from "Star Hustler" to "Star Gazer," to sidestep aggressive web-browsing filters.

The shows are distributed free, via satellite to more than 200 stations across the U.S. and to other outlets like the Armed Forces Network. You can download any of the past year's episodes as well. Since Horkheimer and longtime planetarium colleague Bill Dishong produced several episodes in advance, the last one to feature Horkheimer — his 1,708th — will air the first week of September and feature the Summer Triangle. As always, he begins with a chortling "Greetings, greetings, fellow stargazers and ends with his signature phrase "Keep looking up!"

Beyond the enthusiasm he projected over the air waves, Horkheimer had encouraged kids to get involved in astronomy, most notably through annual $1,000 awards given to aspiring young amateur astronomers through the Astronomical League.

It's not yet clear how or if his show will continue. Tony Lima of the Miami Science Museum, home to the planetarium, says the staff is still trying to make sense of Horkheimer's passing, adding, "We at the Museum all feel this loss quite a bit." At least one month of shows will be hosted by Chris Trigg, another staffer at the Miami facility.

Horkheimer's inspiration will live on. In 2007 Cricket Books published a collection of comic strips (first seen in Odyssey magazine) featuring his madcap take on viewing the sky. Colorful to the end, "Horky" offers this amusing, self-penned epitaph in his online bio:

"Keep Looking Up was my life's admonition,
I can do little else in my present position."