Why do scientists fear that a missile will fall on the moon next month?

The more objects we send to the Moon, the more careful we have to be, and the more difficult it is to apply the criteria.

Researchers expect a floor of an abandoned rocket to fall on the moon's surface early next month, creating a new impact crater, but the potential effects of this fall go beyond - according to scientists - just creating a new hole on the Earth's satellite. What are these effects that worry scientists?

This floor belongs to the SpaceX Falcon 9 rocket, which was launched into space in 2015 carrying NASA's Deep Space Climate Observatory (DSCOVR) probe. And he succeeded in placing it in its orbit 1.5 million kilometers from Earth, facing the Sun, according to a statement published on the European Space Agency's website.

But the upper floor of the rocket did not gain - after performing its mission - enough speed to escape to an independent orbit around the sun, before entering the upper layers of the Earth's atmosphere, where it burns completely, as was customary in most of the previous launch missions in the Earth's atmosphere, which reduces the amount of waste in near-Earth space.

According to the same source, the winged floor - which is 15 meters long and weighs about 3 tons - has taken a wide chaotic orbit around the Earth, so scientists were unable to accurately predict its movement due to its impact on the gravity of the moon, the sun and the earth at the same time.

However, scientists expect - based on accurate calculations - that the rocket floor will fall on the other side of the moon near the equator next March 4 at a speed of about 2.6 kilometers per second, which will create a crater with a diameter of 19 meters.

The news of this expected collision sparked widespread anger on social media, as it was considered irresponsibility on the part of humans that would distort the shape of the moon, but scientists believe that there are other aspects of concern other than those related to distorting the moon.

According to David Rothrey, Professor of Planetary Earth Sciences at the British Open University, in an article published on The Conversation website, the fall of an old missile on the surface of the moon is less harmful to the environment than its burning in the Earth’s atmosphere and the spread of oxides it causes metallic.

Impact craters also accumulate naturally on the moon's surface due to its lack of an atmosphere. Scientists have estimated that there are nearly half a billion craters on the moon with a diameter of 10 meters or more.

In addition, the expected collision will not be the first of its kind. There, for example, the upper floors of the missiles used in the Apollo landing missions crashed, and many vehicles crashed in its airspace, the most recent of which was the Indian vehicle "Vikram" (Vikram) in 2019.

Biological contamination risk

But what to worry about, according to David Rothrey, is the possibility of contaminating the moon with live bacteria or compounds that could be misused as evidence of past life on the moon in the future.

Most nations had agreed to the Planetary Protection Protocol, a set of space mission guiding standards introduced since the 1950s that aim to reduce the potential for biological contamination from Earth to another body (and from another body to Earth), and not to expose any ecosystem that might It is located on another object of danger by bringing species from the earth that may flourish there.

But that did not prevent massive violations, the most recent of which was in 2019, when an Israeli lunar lander carrying DNA samples and thousands of tardigrades crashed onto the surface of the moon.

Tardigrades are creatures about half a millimeter long, which can withstand the vacuum of space without being active in it, and it is possible that these animals, along with the bacteria that reside in their intestines, are now scattered at the site of the vehicle crash.

Although the floor of a rocket that has spent 7 years in space, it likely won't fall into a place with enough water for the bacteria it carries to recover and become active again, "but this is not a risk we should take," as Rothrie wrote in his article, "The more we send More bodies to the moon, we had to be more careful, and it became more difficult to apply standards.