LAFAYETTE — The planetarium at the Lafayette Science Museum is preparing for a giant leap in technology with a $500,000 digital upgrade to replace decades-old equipment.

“It’s a whole new world for the planetarium,” curator Dave Hostetter said.

City-parish government is scheduled to take bids for the upgrade next month.

Work to pull out the old equipment is expected to begin in January and the new digital equipment should be up and running by April, Hostetter said.

Shows at the planetarium are the product of old film and slide projectors and a “star machine” that has been used since the planetarium first opened in 1969 near Girard Park before moving downtown in 2002.

The centerpiece of the planetarium’s current show is the 40-year-old star machine, which mimics the night sky by projecting light through hundreds of tiny holes onto the darkened dome ceiling.

“It’s just, frankly, wearing out. It has been a great star machine, but it has reached the end of its lifetime,” Hostetter said.

Other celestial effects, such as images of comets and planets, are produced mainly by a few dozen film and slide projectors with some unusual handmade modifications.

A sunrise sequence, for example, is produced by projecting a slide of the sun onto a small mirror that is then tilted by an electric motor and reflected through filters colored red, orange and yellow — creating an image on the planetarium’s dome of the movement and colors of the rising sun.

“That’s getting to be dated technology,” Hostetter said.

It is also a bit of a chore to manage the old analog system.

“It’s on the order of some 300 different buttons, knobs and controls,” Hostetter said.

The new system will be controlled by computer, with the digital images of stars and planets emanating from a ring of digital projectors around the perimeter of the dome.

“This is going to be a much more dynamic presentation,” Hostetter said.

He said the digital system will offer a great variety of new options — giving viewers the visual experience of zooming in and out of galaxies and planets, circling a planet or traveling “live through the universe.”

“We could fly to Saturn and show you the rings,” Hostetter said.

Lafayette Science Museum Interim Director Kevin Krantz likened the planetarium upgrade to going from a Fisher-Price View-Master toy to a state-of-the-art television.

“We are bridging a big gap with this system,” he said.

The new digital equipment also takes up less space, which will allow the planetarium to expand seating capacity from 72 to 80, Krantz said.

Hostetter said that the old star machine and some of the other special effects equipment will be kept, possibly for an exhibit in the future.

“It’s an important part of our history,” he said. “In a way, I’m going to miss this stuff.”