An examination of data from a NASA mission that successfully hit its target, such as Dimorphos on September 26, proves that our protected planet can be intercepted by an asteroid or deflected without advancing the probe, the work concludes.
When NASA’s Double Redirection Asteroid Test (DART) successfully impacted its target nearly five months ago, disrupting the orbit of the small moon asteroid Dimorphos in 33 minutes, the weapon team painstakingly analyzed Data collected from the planetary defense’s first test mission.
The rocket mission of the asteroid used a technique called “impact” in motion, which simply means that the object crashes into something else, in this case, a ship into an asteroid. Maryland, it was found that the impactor mission in motion can be effective in bending the trajectory of asteroids, a big step towards the goal of preventing future asteroid impacts on Earth. These findings were published in four articles in the journal Nature.
“I was excited when DART hit an asteroid for the first demonstration of planetary defense technology and that was the beginning,” said Nicola Fox, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “These discoveries add to our fundamental understanding of asteroids and lay the foundation for how humanity can defend Earth from a dangerous asteroid by changing its course.”
The first article reports in detail about the successful demonstration of DART’s kinetic impactor technology: the restoration of the impact itself, the report of the time leading up to the impact, the precise specification of the location and nature of the impact site and the record. on the size and appearance of Dimorphos.
it is the first step
The authors note that a successful autonomous launch of a small asteroid, with limited prior observations, is a critical first step on the way to developing kinetic impactor technology as a viable operational capability. for the defense of the planet.
The findings show that intercepting an asteroid with a diameter of about 800 meters, such as Dimorphos, could be done without an advanced exploration mission, although the advanced exploration would provide valuable information for planning and predicting the outcome. That is enough lead time: several years at least, but rather decades. “However,” the authors state in the article, the success of VERTI “generates hope for humanity’s ability to protect Earth from the threat of asteroids.”
The second paper uses two independent approaches to ground light curves and radar observations. The research team arrived at two constant measurements of the period of the change of motion of the movement: 33 minutes, plus or minus one minute. This large change indicates that the withdrawal of material excavated from the asteroid and its impact into space (known as ejection) has contributed to a significant change in the asteroid, beyond the chest of space itself.
The key to impact in motion is that the impact to the asteroid comes not only from the impact of space, but also from the recoil of this ejecta. The authors conclude that “to demonstrate a proof-of-concept for planetary defense in kinetic impactor technology, it is necessary to demonstrate that an asteroid can be targeted in a fast collision and that the target’s orbit can be changed.” Then she was successfully released. “
moment of change
In a third paper, the research team calculated the change in momentum transferred to the asteroid as a result of the impact of the kinetic energy by studying the change in the phase of the orbital dimorphism. The impact caused an instantaneous slowdown in the speed of Dimorphos in orbit to about 2.7 milliseconds throughout, again indicating that the ejecta played a significant role in amplifying the asteroid’s direct momentum change through space. That momentum change was amplified by a factor of 2.2 to 4.9 (depending on the mass of Dimorphos), indicating that the momentum change transferred due to the thrust output significantly exceeded the ship’s momentum change. DART space only.
This discovery “strengthens the effectiveness of impact motions in preventing future asteroid impacts on Earth,” the authors conclude. The scientific value of the projectile goes beyond confirming the film impactor as a means of planetary defense. The mission to Dimorphos broke new ground in the study of asteroids. The DART impact turned Dimorphos into an “active asteroid,” a space rock that orbits like asteroids but has a tail of material like comets, explained in a fourth paper by the Jian-Yang Li Institute of Science.
Although scientists have proposed that some asteroids are active as an impact event, until now no one had observed asteroid activation. The Dimorphos rocket mission is being reduced under more precisely known and carefully observed impact conditions, allowing for the first time a more detailed study of active asteroid formation.
“DART, as a controlled planetary impact experiment, provides a unique understanding of the target, the morphology of the ejecta and the entire ejecta evolution process,” the authors write. “SPIN will be a model study of recently discovered asteroids that show natural impact activity.”
“We are very proud of Jason Kalirai,” said Jason Kalirai, civil space mission area executive at APL. “In a core analysis of operations that begin after the Dimorphos impact, the results demonstrate how successful impactor motion can be as a technology, paving the way for a bright future for planetary defense.”
