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After almost five decades, it seems that the final resting place of a missing historical material element has been found: a very strange set of lunar features could mark the location where part of the Apollo 12 lunar module has crashed the moon almost two kilometers per second.
This will take a little explanation.
The Apollo 12 Saturn V carrying Al Bean, Pete Conrad and Dick Gordon was launched on November 14, 1969. Four days later, the Lunar Module carrying Bean and Conrad fell from lunar orbit onto the surface of the Moon and landed on November 19th. The astronauts spent a day on the moon, then returned to Earth on November 24 after an extremely successful mission.
On the Moon, they deployed a series of instruments called Experimental Package on the Apollo Lunar Surface or ALSEP. One of these experiments was the passive seismic experiment, designed to detect moon tremors. These tremors can be caused by meteorite impacts, possible volcanic activity, landslides … or they can be created expressly by the man.
How did NASA cause an artificial earthquake? Crushing an Apollo vehicle we do not need anymore on the moon.
The astronauts used two vehicles to get to the moon, then to return to Earth. In addition, each of these was composed of two separate pieces of material.
The command and service module (or CSM) is one of these pairs; the control module was a familiar cone-shaped capsule that returned to Earth and was splashed in the Pacific, and the service module was the cylindrical craft behind the propulsion system (rocket and fuel). This is what brought the astronauts to the moon, slowed them to orbit and brought them home.
In front, there was the lunar module (or LM), the insect-like vehicle that descended to the moon. This one consisted of the phases of descent and ascent. The descent phase (the lower half with the legs) included a rocket strong enough to drop the LM on the Moon's surface, but it was no longer needed afterwards and was dead weight. So, to save fuel, she was left behind, with the ascent phase (the upper part) bringing the two astronauts back into orbit to meet the CSM and the third astronaut (Gordon), who had stayed on the CSM in orbit overnight. landing mission.
Once the Moonwalkers returned to the CSM in orbit, the ascent phase was no longer necessary. Now here's the trick: it broke loose and the remaining fuel was used to desorb it and crush it near the landing site, so that the seismometer could measure the impact. Artificial earthquake!
It was supposed to hit about 10 kilometers from the landing site, but eventually burned the desorbite longer than expected and crashed much further. The problem is that nobody knew where.
Until now. Two scientists may have finally found the site of the impact.
They searched for images taken by NASA's lunar reconnaissance orbiter, which has been creating phenomenal high-resolution maps of the Moon's surface for years. They did not need to look at the entire moon since – since the length of the burn by the desorbite – they knew that the site of the crash was within 80 km of the initial landing site. So they focused on this area. The two authors looked for images individually, without consulting each other, so that they could be independent and not biased. In fact, one of them found the images in question in 2013 and the other in 2016. After that, they worked together on what they had seen.
[Note: I want to be careful here and say that the claims of this being the impact site of the Ascent stage are compelling, but not yet confirmed. So when you read below about the impact site, put an understood “alleged” in front of it.]
They think that the impact site is at a lunar latitude and longitude of 3.920 ° S, 338.828 ° E (click on it to get a panoramic map of the area). They found on the surface a dark trail that corresponds to the trajectory of the stage Apollo 12 Ascent (roughly west by north-west, so mainly from right to left but also a little higher). The series extends about 30 meters long and 4 meters wide, a little narrower and longer than a tennis court.
This corresponds to what is known about the impact of the ascent phase. It was moving at about 1.7 kilometers per second (about twice as fast as a rifle bullet) and the angle of impact was extremely shallow, at around 4 ° compared to the # 39; horizontal. This should leave a groove or hollow dug in the surface.
Dealing with the image to bring out the features, they also spot what looks like a fan of debris blown by the impact, which also has the correct orientation. Given that the climbing stage had a mass of almost 2,400 kilograms, that makes sense as well. He would have hit difficult.
In itself, this would be interesting but not necessarily convincing. But they followed the direction of the northwestern trough and discovered a series of dark trails parallel to the impact mark, starting about 100 meters to the west-northwest. and running for nearly 2.5 km! They interpret this as an impact – blown material that has flown downstream, traveling a certain distance due to low gravity and lack of air resistance.
It's a lot more convincing. And it's better: looking at the topography, they found these trails on the slopes focused towards the site of impact, but not on the slopes facing a way. This is exactly what you expect, as debris has been blown and dropped to the surface. Something moving from a ballistic point of view is unlikely to land on the other side of the hill, and much more likely to hit on its side.
So, case closed? Well no. I have some reservations with the claims. In the wide impact site image that I posted for the first time, there are other trails below and to the left that are approximately parallel to the furrow pathway. impact. I do not know what they are, but their alignment is disturbing. The impact series is the darkest of all, but that does not mean it's really where the impact site was.
In addition, some of the later Apollo missions have also undergone the same process of deorbiting the ascension stages and letting them hit. In no other case, these lower streaks have been seen. It is not necessarily overwhelming; Apollo 12 was perhaps a special case, and it resulted in something to create these streaks, so do not have to arrive with the other missions. This is not a good argument without proof – it is not good to resort to a special pleading. But it's not totally out of the question either; Since there were not many missions, we do not have many examples, and they all hit different places with a different geology, so a weird site is not so stupid.
In my opinion, they are a solid argument, and if I had to bet, I would say they are right … but I would also like to see higher resolution images of the site before I decide.
Incidentally, they also examined the impacts of other missions on the ascent phase, and it will be interesting to see them as well. Maybe they will provide more information on this impact.
With recent announcements from so many private companies and governments claiming to want to go to the moon, I guess it will not be much longer before we have much more information about the moon. We will see the Apollo sites better than it has been since, well, Apollo. Let's hope that many outstanding questions will have an answer, and soon.
Tip o the space suit helmet to my old boyfriend Dan Vergano who tweeted about the paper.
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