The heartbeat soars in the suburbs of Washington DC.., where scientists and engineers hope to see Monday evening how youA vending machine-sized spacecraft 11 million miles from Earth crashes into an asteroid.
If everything goes as planned and the laws of gravity and motion don’t change at the last moment, this will happen at 7:14 p.m. EST – or, to be precise: 7:14:23 p.m.
Nothing major is at stake except the demonstration of technology that could one day save civilization.
It is important to note that the asteroid in question no threat to earth and he did nothing wrong to deserve this attention. But the space collision is a critical moment for the Double Asteroid Redirection Test (DART)), NASA’s first “planet defense” test.
This mission is designed to show how ‘kinetic impactor’ could deflect dangerous asteroid that could hit Earth. There are plenty of space rocks that could disrupt our typically peaceful journey around the sun. The general planetary defense strategy is to alter the orbits of asteroids so that, even as they approach Earth, they pass through without danger.
The DART team members are confident they’ll pull it off, but admit it’s not a resounding success. The spacecraft could crash. There will be no consolation for scientists and engineers if they have nearly reached the goal. They’re not horseshoes or hand grenades: proximity doesn’t matter when it comes to altering the trajectory of an asteroid.
“The success of the mission is pretty clear: you have to hit this asteroid,” said Elena Adams.engineer at Johns Hopkins University’s Applied Physics Laboratory in Laurel, Maryland, who is performing the mission under contract with NASA.
The asteroid is called Dimorphos. It measures about 500 feet (152 meters) in diameter. No one knows exactly what it looks like. In telescopes, it is a fuzzy point. The first time the Earthlings will examine it closely will be less than an hour before impact.
Dimorphos orbits another larger asteroid, called Didymos (Greek for twin), because both orbit the sun. This type of “binary” asteroids is common.
The spacecraft was launched last November from California. The larger asteroid essentially serves as a guide star for the mission. But only the smallest asteroid is the target. When the ship approaches the large Didymos, you should see the small Dimorphos spinning behind its companion. It will be a head-on collision.
Things are bound to be tense in the mission operations room in Laurel. The Applied Physics Laboratory handles a lot of classified government research, but sometimes participates in ingenious space missions. Seven years ago, he successfully piloted NASA’s New Horizons spacecraft near Pluto and obtained the first close-up images of the dwarf planet.
This mission is similar in that it is fraught with pitfalls and uncertainties. The ship must make crucial navigational decisions at the last moment autonomously. Flying a spacecraft at high speed – about 14,000 miles (22,500 km) per hour – towards a relatively small asteroid is something no one has ever done before.
If the DART ship misses the target, it will theoretically have a second chance to encounter Dimorphos in two years.but the engineers do not even dream of breathing a little.
Previous space science missions by NASA and the Japanese space agency have sampled asteroids, but they have been carefully choreographed encounters with incremental approaches. DART anticipates a high-speed crash. The scientists and engineers behind the mission say they won’t know if they will collide with the asteroid until around 20 seconds before impact.
“Asteroids are extremely dark,” Adams said. “We have to hit something that is the size of two stadiums. They can only be seen an hour before they hit them (…). Even then, it’s just one pixel in our camera.”
Mission engineers are making final adjustments to the spacecraft’s trajectory, but the final approach, in the hours before the predicted collision, will be automatic. A camera on board the spacecraft will capture images of the smaller asteroid while helping the vehicle focus on the target.
The final images transmitted by the spacecraft camera will show a small white dot transforming into something brighter, bigger and more asteroid. Then, if all goes according to plan, Dimorphos will come out so large that it fills the field of vision.
And it will be the last thing seen when the spaceship makes the ultimate sacrifice.
Telescopes on Earth, as well as Webb and Hubble in space, will also observe the impact.
The most worrisome asteroids with potential global climate repercussions are those over a kilometer in diameter. These are the easiest to spot. More than 95% of the estimated population of these killer rocks have been identified, said planetary scientist Nancy Chabot, the DART coordinator.
Less than half of the asteroids between 140 meters and 1 kilometer have been identified. It is an ongoing effort. Boulders of this size – and Dimorphos is one of them – could level a large city with a direct hit. Chabot said early detection is key to planetary defense.
“It’s something that doesn’t happen at the last moment. It’s something that happens years in advance,” he said.
NASA and its partners currently have a catalog of 30,000 objects, said the agency’s planetary defense chief Lindley Johnson. Scientists can calculate their orbits for a few decades into the future, but as the timeline lengthens, the orbital uncertainties increase.
No dangerous asteroids appear to be on the verge of colliding with Earth at this time, as far as those things can be calculated, Johnson said. But he will keep a close eye on Monday night’s asteroid redirect test.
“We have to have this technology,” he said. “It would be wise for us to test all of this beforehand, so we’re not trying this for the first time when we really need it to work.”
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