After entering lunar orbit last week, Israeli spacecraft Beresheet on Monday morning successfully performed another maneuver as it entered ever-tighter orbits around the moon, before attempting to land on April 11 in the Sea of Serenity.
The maneuver reduced the maximum distance of the spacecraft’s elliptical path around the moon from 750 kilometers (466 miles) to 467 kilometers (290 miles). Its current minimum distance is just 210 kilometers (130 miles).
On Sunday, Beresheet successfully performed the first in the series of maneuvers and all of its engines were turned on for 271 seconds, burning 55 kilograms (120 pounds) of the fuel it has left.
In the three days remaining until the landing attempt, engineers will perform further maneuvers to turn Beresheet’s current elliptic orbit into a circular orbit 200 kilometers (125 miles) from the face of the moon.
On Thursday, Beresheet’s engineers executed the most complicated maneuver yet, a perfectly choreographed space hop allowing the car-sized spacecraft to jump from an orbit around Earth to one around the moon — making Israel the seventh country in the world to achieve the feat.
In order for the spacecraft to successfully enter into orbit around the moon, Beresheet needed to slow down from 8,500 kilometers per hour (5,280 mph) to 7,500 kph (4,660 mph). Although that still seems fast to mere humans, according to engineers, it is the orbital equivalent of slamming on the brakes. The engineers accomplished this by turning the spacecraft so that its engines thrust in the opposite direction, slowing down the speed.
It took about nine minutes for eight engines to slowly maneuver the spacecraft in the right direction, and a little less than six minutes for the engines to slow the spacecraft down to the correct speed.
The United States, Russia (as the USSR), Japan, China, the European Space Agency and India have all made visits to the moon via probes, though only the US, Russia and China have successfully landed on the moon; other probes crashed-landed on the surface.
If Israel successfully lands as planned on April 11, it will also be the first time that a privately financed venture has landed there.
The NIS 370 million ($100 million) spacecraft is a joint venture between the Israeli nonprofit SpaceIL and Israel Aerospace Industries, funded almost entirely by private donations from well-known Jewish philanthropists.