Saturday , April 17 2021

Like the asteroid Flyby in 2017, NASA is helping to defend the country from Armageddon

A very strange series of memoranda arrived at the White House in the fall of 2017, which describes a nightmare scenario: The asteroid is obviously on its way to hit the Earth. But these notes were covered by bright red warnings, noting that they are only part of the exercise; humanity has no more reasons than to be afraid of civilization.

The notes were part of a surreal, sophisticated exercise that allowed NASA and the scientific community to practice an existential threat from an asteroid which appears to be on the way to hit the Earth – is based on a true asteroid. And now, the team involved in the exercise published a final set of findings on how the project was going and what people can do to be better prepared for this potentially scenario of apocalypse.

"The most important thing is [that] it was the first time we tested the entire system, including reporting to the White House, "said Vishnu Reddy, a planetary planetary expert at the University of Arizona and co-author of the new document, for last month at an annual conference on moon and planet science which was held in Shundield, Texas. "It was a really fantastic test for a true asteroid test."

Related: Mankind will spy space spacecraft in asteroid for several years to help us preserve all

In early 2017, scientists decided they wanted to carry out such an exercise. So they went looking for an asteroid, which was not really a risk, but it would come close enough to produce realistic data on how the real risk can be played. It will allow planet defense experts, who are studying the threat of asteroid impacts exclusively, to test their monitoring, evaluation and response procedures.

Space rock known as 2012 TC4 corresponds to the law. During the initial detection of this facility in 2012, observations on its way through the solar system suggested that they would make the approximate but not dangerously close access to Earth in October 2017, although the researchers were not positive exactly what would be needed .

So the asteroid got its role as a guinea pig for the end of the world, as we know it.

"We knew it was not a threat … we wanted it to be an exercise, but TC4 was a good candidate," said Michael Kelley, a NASA scientist in the planet defense program and co-author of the review document, during a presentation at the same conference. "It was an asteroid with a little uncertain orbit that was in the time frame we were seeking to carry out this exercise. We knew it was there." We knew roughly where to look at the sky, but we did not know exactly where to direct the telescopes, so we would need let's crawl a bit to try and find it. "

That search started in July 2017, when the team used it Very large telescope in Chile began to try to spot TC4. They stood up for good in August, when they expected they could. A different telescope, Pan-STARRS in Hawaii, they also showed separately that if scientists did not have the 2012 data, they would still notice the asteroid about two weeks before the close approach by 2017.

As TC4 approached, scientists turned telescopes around the world to the facility. First, they looked to follow their path. Observers and orbital trajectory specialists worked together to rebuild their expectations as to where exactly the rock would be, one of the key responsibilities of the planetary defense. As the picture was developed, the team submitted the data to government officials to discuss how the situation in real life would unfold.

The good news is that you have never heard of a major asteroid that struck Earth in the autumn of 2017. The more complicated finding was that there was a time when team calculations suggested that this was a realistic opportunity, said Kelly. In short, on 24 September that year, the calculations gave TK4 1 a chance to hit the Earth. "This is well below the threshold to open up all triggers for an emergency," Kelly said.

Fortunately, within just a few days, there was a chance evaporates. However, uncertainty makes a risky situation, he added, as the team never wants to act hurriedly and cause panic. But someone who did not follow the whole process could take data one day out of context, deliberately or not.

"You have to be very, very careful when you have a lot of measurements coming and waiting to see what fits the model and what's wrong with the model," said Kelly. "You can get to the point where you draw a wrong conclusion, if you stop at a certain point, or if you simply take the picture".

By the end of the exercise, the team completely eliminated the likelihood of impact from TC4 in the foreseeable future.

But scientists were unhappy with simply predicting the asteroid path; they also wanted to collect as much data as possible on the cliff itself. In particular, they examined how it was darkening and lighting up it spuns into space. In the context of a potential drummer, this information is not only scientifically interesting. More than that, the details of the rotation and composition of the asteroid can shape the potential catastrophe, affecting how much of the initial mass makes it through the destructive atmosphere of the Earth.

Here, too, things have become a little dicey. The team set up a number of facilities that they wanted to use in advance, but the fate intervened. Scientists wanted to use it mass radio antenna in Arecibo in Puerto Rico to unleash light waves from the surface of the asteroid and see how they are coming back. But Hurricane Marija devastated the island just weeks before the closest approach to the asteroid, and the telescope was not ready to help. Scientists had to race with ropes in two other radio telescopes, Goldstone and Green Bank, to complement the absence of Arecibo.

And the team wanted to use Hawaii's infrared NASA telescope to better understand the composition of the object. The telescope had a window of three nights to capture TC4. She watched the asteroid on the first night and was placed on another task of the latter. On the third night, the power came out.

"It turns out that someone cut the tree and the tree fell on the electrical line," said Reddy. "And so, the fate of the world will end [the hands of] a person with an ax in his hand who tries to cut a tree in the evening. "

There is no reason to doubt that the same kinds of secular issues will be patiently waiting for a real threat. "There are problems in the real world that can occur even in an emergency situation," Kelly said. "Bad timing is always there".

Despite the challenges during the observations, scientists are quite satisfied with what they learned about TC4. It seems to be very bright, about 10 feet (10 m) in diameter, with a sharp, uneven surface. "This can be a fragment of a very bright, white rock in space," Kelly said. It seems to resemble an unusual type meteorite – a kind that makes up only 1% of the space rocks that we have here on Earth – called aries.

Now that the results of the TC4 exercise are published, the team is ready to apply the lessons learned during the exercise of the new exercise. That team chose a different asteroid, again based on the orbital comfort of the object. "We can not schedule an asteroid[s]. We should wait for them to cooperate, "said Kelly.

This exercise will be on a smaller scale than that of TC4, in order to just learn as much as possible about the spatial rock itself – although scientists already have a good sense of what it is.

"We know a lot, but we pretend we do not know," said Reddy. "Imagine if this asteroid hits us, say, 15, 20 years from now and this is the last, best spillover when we can characterize it so that we know what to do next 15, 20 years before impact. Learn?"

This kind of preparation is not just for learning distant cosmic rocks sailing through the solar system. It also means learning about deeply land-based, deeply human factors, how to be prepared if someone smashes the wrong tree on the wrong day.

"This exercise was actually a good lesson in reality to try to do it in practical terms," ​​Kelly said. "The events in the real world affected the campaign, but we dealt with them and worked through it." And as a result, people should be better prepared for the next close approach.

"Fortunately, the fate of the Earth did not ride on this, so we are fine," he said.

The project is described in paper released in March in the Icarus magazine.

E-mail Meghan Bartels at [email protected] or follow it @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

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