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The 150 or so audience members who came to the Addison-Penzak JCC in Los Gatos on Oct. 30 Tuesday night to hear about Israel’s first lunar spacecraft are all going to the moon.

Well, they’re not actually lunar-bound themselves. In fact, the SpaceIL craft that would make Israel the fourth nation to land a vehicle on the moon doesn’t have room for any live beings, human or otherwise.

But Yonatan Winetraub, one of the three Israeli co-founders of SpaceIL, took selfies and pictures of the JCC audience that will go to the moon in a time capsule containing pictures from Jewish communities around the world.

“It’s going to be on the moon,” Winetraub explained, “so you might as well smile.”

The time capsule will be about the size of a grapefruit. The spacecraft itself, which is scheduled to launch early next year, will be the smallest ever to go to the moon — it’s about 5 feet tall and weighs just 1,290 pounds, including about 940 pounds of fuel.

Thus, there won’t be any room for humans, and the flight will be unmanned. Keeping the cost down meant everything had to be limited in size.

“Small spacecraft, small country, small budget, so no room for oxygen,” Winetraub said.

If the launch and lunar landing are successful, Israel would join the United States, the Soviet Union and China as the only countries to reach the moon — unless an Indian craft set for takeoff at about the same time jumps ahead and pushes SpaceIL down to No. 5.

The SpaceIL project was inspired by a $20 million reward offered by the Google Lunar XPRIZE challenge to build, launch and land an unmanned spacecraft on the moon. The Israeli entry — dreamed up in 2011 by Winetraub and two fellow engineers over beers at a bar in Holon, Israel — was one of five finalists out of the original field of more than 30.

The Israeli entry was the only one by a nonprofit organization, and the founders planned to donate their prize to fund education of scientists and engineers in Israel if they won. But the competition ended in March when Google, which had extended the deadline several times, withdrew the prize because teams couldn’t finish their missions.

Winetraub and his buddies decided to continue with their $95 million project anyway, in hopes it would inspire scientific study among Israeli kids. Construction of the craft is complete, and testing is now underway at Israel Aerospace Industries labs, located next to Ben Gurion Airport.

NASA announced in early October that it will help the SpaceIL team improve its communications with the lunar vehicle, in part by installing an instrument on the craft that reflects laser beams. In return, NASA will have access to data gathered by a magnetometer installed on the Israeli spacecraft, part of a Weizmann Institute of Science experiment.

Small spacecraft, small country, small budget.

The need to keep costs down required other unusual measures. When the craft is launched next year in Cape Canaveral, Florida — on one of Elon Musk’s SpaceX rockets — it will be sharing the ride with several satellites. That means the SpaceIL craft’s trip to the moon will take more than two months, instead of the three days it would have taken on a direct trajectory.

“The problem with rockets is that they are very, very expensive,” Winetraub said. “Apparently, a spacecraft is not something you can build in your backyard.”

The “low-budget” project also means there were virtually no redundant systems built into the craft in case something fails.

“The spacecraft is going to be the bare minimum of what it takes to get to the moon. We want to show you can do it with a small spacecraft,” he said. “There are thousands of pieces that have to work perfectly, but in the end you have to cross your fingers and hold your breath. It’s a risky mission. We just couldn’t afford [backup components].”

Winetraub is studying for his doctorate in biophysics at Stanford University, focusing on a method to interpret and intercept cancer cell communications. Before that, he was part of the International Space University program at NASA’s Ames Research Center in Mountain View, concentrating on how to create colonies on Mars.

He studied electrical engineering and computational neuroscience at Tel Aviv University, and worked as a satellite system engineer for Israel Aerospace Industries.

Getting kids to follow his educational path is part of the motivation of going to the moon.

“If you study science today, in a few years you can build your own rocket ship,” Winetraub told kids in the audience. “Our spacecraft will stay on the moon. Your job is to bring it back.”