What happens when galaxies collide? (Watch the drama.)

How do you take a star's temperature? (Tip: Thermometers don't work.)

How high can you launch a rocket? (Yes, you!)

The annual celebration of space science and all things astronomical lifts off tomorrow at the University of Hawai'i Institute for Astronomy's annual open house at space headquarters on Woodlawn Drive.

New this year is "Astronomy School," where visitors can measure the speed of a galaxy, analyze the light from a star, and track the gyrations of Jupiter's moons.

"We want to give visitors a hands-on experience of observing how professional astronomers do it," said astronomer Helene Courtois. "Budding scientists will earn an 'Honorary Astronomer' certificate for finding a star and collecting data from it using our telescope simulator software."

Budding astronomers and astronauts also get to play Astro-Jeopardy, simulate a Mars landing using raw eggs (a big splash last year), and travel through space in the Institute Starlab planetarium.

Away from the floating eggs and rocket launches in the IFA courtyard will be exhibits, demonstrations and tours of the research laboratories. Visitors can check the construction progress on the world's largest digital camera for the Pan-STARRS project to hunt for asteroids.

Family talks will cover topics including Pluto, dark matter and ancient Hawaiian astronomy.

Telescopes will be on hand, of course, to view Venus and the sun, plus advice for amateur astronomers on how to buy and use telescopes and astronomy software.