The Falcon 9 rocket was originally launched from Florida in 2015 to deploy the Deep Space Climate Observatory and has been following a “chaotic” orbit ever since.
The SpaceX rocket is on a collision course with the moon after nearly seven years in space, experts say.
The rocket was originally launched from Florida in February 2015 as part of an interplanetary mission to send a space weather satellite on a million-mile journey.
But after completing a long engine run and sending the NOAA Deep Space Climate Observatory to the so-called Lagrange Point – a gravity-neutral position four times farther from the Moon and in line with the Sun – the rocket’s second stage became derelict.
At that point, it was high enough that it didn’t have enough fuel to return to Earth’s atmosphere, but it also “didn’t have enough energy to escape the gravity of the Earth-Moon system,” explained meteorologist Eric Berger.
“That’s why it’s been moving in a somewhat chaotic orbit since February 2015,” Berger added.
Space experts believe the rocket – about four metric tons of “space junk” – has been on its way to crossing the moon at about 2.58 kilometers per second for several weeks.
Bill Gray, who writes software for tracking near-Earth objects, asteroids, small planets and comets, said the Falcon 9 upper stage is likely to crash into the far side of the moon, near the equator, on March 4.
The data analyst said in a recent blog post that the object “made a close flyby of the moon on Jan. 5” but will make “a definite impact on March 4.”
“This is the first unintentional case of space debris falling on the moon that I am aware of,” Gray added.
The exact location of the rocket’s impact remains unclear because of the unpredictable effects of sunlight “pressurizing” the rocket and “ambiguities in the measurement of rotation periods” that could slightly alter its orbit.
“These unpredictable effects are very small. But they will accumulate from now until March 4,” Gray wrote, adding that further observations are needed to refine the exact time and location of the collision.