“It’s such a change from the bad weather that’s in Europe,” said Eugenie Niarchos. “I love being in L.A.”

On a 70-degree November night – about 21 degrees Celsius for the European crowd – the jet-setting heiress and jewelry designer was in town for the launch of Venyx, her newest collection and her fourth to date.

“We have three moons tonight,” she said, pointing to the two oversized planet-like balloons floating above Just One Eye’s rooftop, where she threw an astronomy-themed dinner party for the occasion. (The collection was inspired by the four elements – Earth, Water, Air and Fire.)

Just One Eye for Eugenie Niarchos: Inside the Party

She’s been passionate about astronomy since she was a kid, she said. “And I always loved science fiction, Star Wars, Star Trek.”

“Oh my God, this is sick,” said actress Haley Bennett, eyeing a necklace as she perused the shop, which was bare of all except Niarchos’ newest and previous collections, full of celestial objects.

It was certainly Niarchos’ night, as she was surrounded by friends and family, including her father Philip Niarchos, mother Victoria, sister Electra and brother Theodorakis. There was Demi Moore with daughter Scout Willis and close friend Eric Buterbaugh; Florence and Serge Azria, Olivier Martinez, Rebecca Dayan, Carolina Santo Domingo, Pixie Lott, Benedikt Taschen and Vito Schnabel.

“It’s been lovely,” said Niarchos, who was decked out in her own jewelry. “I was really able to show my brand identity tonight, and that’s what I was really looking forward to show.”