(UPDATE: Successful burn!) The first private spacecraft likely to land on the Moon has to ace a critical engine burn at 10:45 a.m. Eastern Standard Time today, or it won’t make it.
The hydrazine-fueled main engine mounted to the base of the Israeli Beresheet lunar lander is set to ignite around 1415 GMT (10:15 a.m. EDT). The six-minute firing will reduce Beresheet’s velocity relative to the moon by more than 600 mph (about 1,000 kilometers per hour), enough for lunar gravity to capture the spacecraft in an elongated orbit.
If the robotic spacecraft misfires Thursday, it will continue past the moon and escape Earth’s gravitational grasp to head deeper into the solar system, bringing the mission to an end.
“It’s a simple maneuver, but it’s very important and very critical,” said Ido Anteby, the CEO of SpaceIL, the non-profit organization that led the development of the Beresheet mission.
Leonard David in at Space (dot) com writes:
As Beresheet approaches landing, each lunar orbit will last only two hours. And it everything works out, the spacecraft will make an autonomous landing on the moon’s Sea of Serenity on the evening of April 11.
That will be an epic moment: To date, only the governments of the Soviet Union, the United States and China have pulled off a soft landing on the moon.
SpaceIL was one of the competitors in the Lunar X-Prize competition. Others dropped out when the prize was rescinded when no-one achieved the schedule, but SpaceIL continued on their own. A landing on the 11th would be a significant achievement.
Beresheet rode into space on a SpaceX Falcon 9, because of course it did. So many things happening at the same time now!
UPDATE: from Space News:
The lander fired its main engine for six minutes starting at 10:18 a.m. Eastern time, slowing the spacecraft down by about 1,000 kilometers per hour, enough for it to be captured into orbit around the moon. SpaceIL said in a statement that that maneuver went as expected, putting the spacecraft into an elliptical orbit with a perilune of 500 kilometers and apolune of 10,000 kilometers.
“After six weeks in space, we have succeeded in overcoming another critical stage by entering the moon’s gravity,” said Ido Anteby, chief executive of SpaceIL, in a statement. “We still have a long way until the lunar landing, but I’m convinced our team will complete the mission to land the first Israeli spacecraft on the moon, making us all proud.”
Beresheet launched Feb. 21 as a secondary payload on a SpaceX Falcon 9 rocket, which released the spacecraft into an elliptical orbit around the Earth. The spacecraft subsequently performed a series of maneuvers to raise the apogee of its orbit to more than 400,000 kilometers. That put the spacecraft on a trajectory to approach the moon and, after this latest maneuver, enter orbit around it.
Beresheet will later move into a circular orbit 200 kilometers high in preparation for its landing attempt, scheduled for April 11. The spacecraft will try to touch down softly on Mare Serenitatis, or Sea of Serenity, in the northern hemisphere of the near side of the moon.
Here is a good summary of the Beresheet mission and history. It could be noted that Apollo 17, the last US Moon mission, also landed in the Sea of Serenity.
Video from what I assume is the headquarters of the company in Israel: