A SpaceX Falcon 9 rocket upper stage is set to slam into the moon a month from today (February 4).
In February 2015, the Falcon 9 launched the Deep Space Climate Observatory (DSCOVR), a joint mission between the US National Oceanic and Atmospheric Administration (NOAA) and NASA.
The rocket carried DSCOVR to the Earth-sun 1 (L1) Lagrange point, a gravitationally stable point about 930,000 miles (1.5 million kilometers) from Earth. After getting there, the upper stage ended up pointing away from our home planet.
“This made de-orbiting impossible to eliminate it in our planet’s atmosphere, while the upper stage also lacked sufficient velocity to escape the Earth-Moon system. Instead, it was left in orbit chaotic orbit around the sun near the two bodies,” European Space Agency (ESA) officials wrote in a statement on Wednesday (February 2).
The upper floor’s time in space is now nearly up: it hit the moon on March 4calculated the observers.
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Man-made objects have already been intentionally aimed at the moon, as far back as the 1950s. The practice was common at the time. Apollo Programwith rocket upper stages even used to induce “moonquakes” for surface seismometers to pick up.
But the coming SpaceX The lunar crash is quite different, marking “the first time that human-made debris has unintentionally reached our natural satellite”, ESA officials wrote. (“Debris” does not include spacecraft that crashed while trying to land on the moon, such as Israel’s Beresheet probe in 2019.)
“Falcon 9’s upcoming lunar impact illustrates the need for a comprehensive regulatory regime in space, not only for economically crucial orbits around Earth, but also for the moon“said Holger Krag, head of ESA’s space security program, in the same statement.
“For international astronauts, no clear guidelines currently exist to regulate the end-of-life disposal of spent spacecraft or upper stages sent to Lagrange points,” ESA officials wrote in the press release. “Potentially crash into the moon or come back and burn in earth’s atmosphere have so far been the simplest default options.”
The Falcon 9 upper stage will hit the Moon on March 4 at 7:25 a.m. EST (1225 GMT) on the far lunar side near the equator, according to observer calculations. This is only an estimate, albeit accurate; follow-up observations should enhance the accuracy of predictions.
One such calculation comes from astrodynamics engineer Michael Thompson of Advanced Space in Westminster, Colorado. He generated a plot and a visual to show where the upper floor can crash.
Thompson relied on the work of Bill Gray of Project Pluto, which collects and analyzes observations of near-Earth objects. It was Gray who discovered SpaceX’s upper-stage crash course.
Project Pluto publishes a subset of raw observations made by users around the world. Using these observations, Thompson performed his own orbit determination process in addition to the processes performed by Gray.
Advanced Space has generated predictions currently showing an impact west of the Sea of Tranquility, very similar to the prediction generated by Gray.
The impact will be close to the lunar limb as seen from Earth, according to these calculations. Most of the cast lies slightly on the other side of the moon. Based on current data, the impact is not expected to be near NASA or Chinese Apollo lunar exploration sites.
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The impact may or may not be visible from Earth, Thompson noted.
The predicted impact area is far from the current location of China Chang’e 4 lander-rover duo; it is much closer to the lunar limb than completely on the other side.
Even given the large uncertainties in the attitude of the rocket body and the resulting uncertainties in the effects of solar radiation pressure on it, an impact much closer to Chang’e 4 is unlikely, a Thompson added.
The uncertainty will decrease further once additional observations are made this month.
“NASA’s Lunar Reconnaissance Orbiter (LRO) will not be able to observe the impact as it occurs,” explained a NASA statement sent to Inside Outer Space.
“However, the mission team is assessing whether observations can be made of any changes to the lunar environment associated with the impact and will later identify the crater formed by the impact. This unique event presents an exciting research opportunity. “, added the statement from NASA.
“Following the impact, the [LRO] The mission can use its cameras to identify the impact site, comparing old images to images taken after the impact. The search for the impact crater will be difficult and could take weeks or even months.”
Leonard David is the author of “Moon Rush: The New Space Race” (National Geographic, 2019). A longtime writer for Space.com, David has been reporting on the space industry for more than five decades. Follow us on twitter @Spacedotcom Or on Facebook.