Photo by David Yamamoto, Special to the Star

Volunteer Gary Bostrup uses a Cassigreen telescope to look at the moons of Jupiter on Saturday during the National Park Service Winter Sky Star Party at Paramount Ranch in Agoura Hills. The event featured lectures and a constellation tour given by CLU professor Mike Shaw and astronomers from the National Park Service and the Griffith Park Observatory.

Light from a half-moon dimly lit the field Saturday night as volunteers trained their telescopes on Jupiter, its four satellites, the Orion Nebula and the Andromeda Galaxy.

The National Park Service's Winter Star Party attracted more than 400 amateur astronomers, stargazers and science fans to the Paramount Ranch in Agoura Hills to catch a glimpse of the celestial bodies.

Saturday's moon, between the new and first-quarter phases, was just bright enough not to drown out the stars. The brightness also accentuated the moon's own grooves and craters, making it one of the party's main attractions.

"I absolutely love astronomy, and I think it's vitally important that we keep eyes in the sky somehow," said volunteer Colin O'Mara-Green, who works part-time at the Griffith Park Observatory. "It gives us an idea how insignificant we are."

The moons of Jupiter the rocky Callisto, Earth-size Ganymede, volcanic Io and icy Europa lined up almost perfectly with the giant gas planet through O'Mara-Green's telescope.

Photo by David Yamamoto, Special to the Star

Valerie Landon points out a constellation to her daughter Brooke Landon, 5, on Saturday at the Winter Sky Star Party at Paramount Ranch in Agoura Hills.

"Europa is covered in ice water ice," O'Mara-Green said to an eager young scientist.

Read more:

Astronomy buffs gaze at stars in Agoura Hills' Paramount Ranch