SpaceX is set to launch a Falcon 9 rocket on Thursday night, and while it may not be the primary payload, a small Israeli lunar lander is by far the mission's most intriguing payload.

The 180kg Beresheet spacecraft, privately developed by SpaceIL in Israel and funded largely through philanthropy, will spend more than six weeks raising its orbit and becoming captured into lunar orbit before finally making the first private attempt to land on the Moon. Until now, only the US, Russian, and Chinese space agencies have ever successfully landed on the Moon.

This means there is a lot of pressure on the small Israeli team leading the mission, both in their native country and among the commercial lunar community, which wants to prove that private ventures can do what only nations have done before. "What it means to me is that the responsibility is very high," said Yoav Landsman, a senior systems engineer for the project, in an interview.

The first step into space may come Thursday night, with the launch of a Falcon 9 rocket from Florida. The primary launch window for the mission opens at 8:45pm ET (01:45am UTC Friday) for a flight from Space Launch Complex-40 at Cape Canaveral Air Force Station. The main payload is a geostationary communications satellite, PSN-VI. The weather forecast is optimistic.

A long road

An Israeli corporation, SpaceIL was formed a day before the deadline in 2011 to enter Google's Lunar XPrize competition to land a rover on the Moon. At first, the project was led mostly by volunteers, but by 2013, the team realized that if they were going to make a serious run at actually reaching the Moon, they needed professional help.

So SpaceIL began raising tens of millions of dollars from philanthropists such as Morris Kahn, and it staffed up. Landsman was among the hires who joined—he couldn't resist the opportunity to be part of a small team to land on the Moon.

The challenges were immense. They could not afford to buy their own rocket launch, so SpaceIL had to tag along as a ride-share on a mission (they settled on SpaceX in 2016). Because of this, and funding limitations, their spacecraft had to be small, with a limited amount of fuel. The Falcon 9 rocket would drop the Beresheet spacecraft into an elliptical orbit with an apogee of about 60,000km. From there, they would have to get to the Moon on their own.

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

Space IL/YouTube

SpaceIL has released a video, screen-capped above with notes from Landsman, that explains their journey to the lunar surface from launch on February 22 through a projected landing on April 11 in the Sea of Serenity.

On the Moon

Engineers designed the spacecraft to satisfy the demands of the Lunar XPrize, which ended last March without a winner. That competition required a privately funded robot to land on the Moon, travel more than 500 meters, and return high-definition images and video to Earth. Originally, Landsman said they designed the lander with the intent to hop, but now that the contest has ended, the engineers concluded that one soft landing is enough for this mission, and risking the first Israeli heritage site on the Moon made no sense.

The Beresheet vehicle will document its surroundings within a limited lifespan on the Moon. After about three days, Landsman said the vehicle's solar panel are expected to reach a temperature of 200°C and overheat. This was one of the compromises of developing a smaller lander on a tight budget.

So Beresheet will land with urgency, take images and video, transmit them back. When Beresheet is not taking video, it will be attempting to transmit data back to Earth via NASA's Deep Space Network. "We have to hurry and start to download data immediately after landing to get everything back to Earth," Landsman said. If the solar panels last longer, the team will be able to return higher-definition images.

This landing attempt comes as NASA has asked several US companies—some of which were also competing in the Lunar XPrize—to develop the capacity for small landers to deliver science experiments to the Moon. Earlier this month, NASA's science chief, Thomas Zurbuchen, said he would like at least one of those missions to fly by the end of the year, but it's not yet clear whether any of the American companies can deliver.

Certainly, they'll all be watching SpaceIL's attempt to make the first private landing. "The people that were competing with us until not long ago have come to me and told me they are rooting for us," Landsman said. "If we succeed in our mission and show the world we can soft land on the Moon with a privately funded spacecraft, it means the technology is already here."