It is all by chance, but it will create some chaos. NASA has chosen SpaceX, the rocket company founded by Elon Musk, to provide the spacecraft that will transport astronauts to the moon in the future. However, in the meantime, a 4-ton upper stage of a SpaceX rocket launched seven years ago is expected to collide with the moon on March 4, according to recent observations and calculations made by amateur astronomers. The impact is anticipated to occur at 7:25 am Eastern time, although there is still some uncertainty surrounding the exact timing and location. Bill Gray, creator of Project Pluto, a set of astronomical software used for calculating the orbits of asteroids and comets, stated that the rocket piece will not miss the moon. Gray stated that it is highly likely that a predicted object will collide within a few minutes and a few kilometers of its projected location. Throughout the Space Age, human-made objects have ventured into the solar system, with some not expected to return, such as Musk's Tesla Roadster launched by SpaceX's Falcon Heavy rocket in 2018. However, some objects do return, like a mystery object discovered in 2020 that was actually a part of a rocket launched in 1966 during NASA's Surveyor missions to the moon. Gray has been monitoring a specific piece of SpaceX debris that aided in launching the Deep Space Climate Observatory for the National Oceanic and Atmospheric Administration on February 11, 2015. The observatory, also known as DSCOVR, was originally called Triana and was championed by Al Gore as an Earth observation mission. It was later repurposed as a solar storm warning system and now regularly captures images of Earth from space, including rare occurrences like the moon crossing in front of the planet. Typically, the upper stage of a Falcon 9 rocket is intentionally pushed back into Earth's atmosphere after delivering its payload to avoid creating space debris. The upper stage of the rocket used all its fuel to propel DSCOVR to its destination, leaving it in a high, elongated orbit around Earth that could potentially lead to a collision in the future. The motion of the Falcon 9 stage is influenced by the gravitational forces of Earth, the moon, and the sun, as well as sunlight pressure. While debris in low-Earth orbit is closely monitored for satellite and International Space Station safety, more distant objects like the DSCOVR rocket are often overlooked. Gray claims to be the only person tracking these objects. Many spacecraft that have been sent to the moon have crashed there, but it seems that this is the first time something from Earth not intended for the moon will end up there. On January 5, a rocket stage passed within 6,000 miles of the moon, and its trajectory was altered by the moon's gravity, potentially causing it to eventually intersect with the moon. Gray asked amateur astronomers to observe the object as it passed by Earth in January, and one of those who responded was Peter Birtwhistle, a retired IT professional living near London. The Great Shefford Observatory's 16-inch telescope in his garden tracked a rocket stage moving quickly through the sky, allowing Birtwhistle to predict its impact trajectory. Astronomers will have one more opportunity to observe it before it swings out beyond the moon and ultimately hits the far side, hidden from view on Earth. NASA's Lunar Reconnaissance Orbiter will not witness the impact live, but it will fly over the site afterward to capture images of the newly formed crater. Mark Robinson, a professor at Arizona State University and the principal investigator for the orbiter's camera, estimates that the impact of 4 tons of metal traveling at a speed of 5,700 mph will create a crater 10 to 20 meters wide. This will provide scientists with valuable information about what lies beneath the moon's surface, unlike meteor strikes where the size and timing are unknown. India's Chandrayaan-2 spacecraft, also in orbit around the moon, may also be able to photograph the impact site. Other spacecraft that are scheduled to travel to the moon this year may have the opportunity to observe the impact location, unless they also accidentally create new craters. ©2022 The New York Times Company.