NASA’s DART mission is a step toward preparing the world for a possible future asteroid strike.
NASA’s DART mission is a step toward preparing the world for a possible future asteroid strike like the one that killed dinosaurs some 66 million years ago, the odds of which are very slim in our lifetime, Indian scientists said. .
In a unique mission, the Double Asteroid Redirection Test (DART) spacecraft successfully crashed into an asteroid on Tuesday to test whether space rocks that could threaten Earth in the future can be safely pushed out of the way.
DART – the world’s first demonstration of planetary defense technology – targeted the asteroid moon Dimorphos, a small body just 160 meters in diameter.
“We are surrounded by several asteroids and comets that orbit our sun. Few of them are potentially dangerous to Earth. Therefore, it is better to prepare our defenses to prevent such asteroids on a collision course with Earth in the future.” to avoid,” said Chrisphin Karthick, a scientist at the Indian Institute of Astrophysics (IIA), Bengaluru.
Karthick, who is involved in the DART project, noted that the mission is “certainly a step toward” preparing the world for a possible future event like the one believed to have led to the extinction of dinosaurs. about 66 million years ago.
“This successful DART mission is an example of that. We now know exactly how to target the spacecraft at such a small body. We can also prepare for the larger body with the post-impact observations from this DART mission,” Karthick told PTI.
Dimorphos orbits a larger 780-meter-long asteroid called Didymos. Neither asteroid poses a threat to Earth. By comparison, the dinosaur-killing asteroid that hit Earth was about 10 kilometers in diameter.
The one-way DART mission, NASA confirmed, can successfully navigate a spacecraft to deliberately collide with an asteroid to deflect it, a technique known as kinetic impact.
Goutam Chattopadhyay, a senior scientist at NASA’s Jet Propulsion Laboratory (JPL) in the US, also noted that the mission will help prepare for a future-threatening asteroid.
“DART is an experimental mission to try out a concept for deflecting an asteroid. The idea is that if we can encounter these asteroids whose trajectory is toward us and we do it at a sufficient distance from Earth, a small deflection will be enough to change the path of the asteroid,” he added.
However, scientists noted that most asteroids, which are quite large and can cause damage when collided with Earth, have a miniscule chance of hitting the planet.
“However, the probability of that is non-zero and we must always be vigilant. There is always a possibility that a big one is coming our way and the question becomes, what our approach would be and how we can reduce it. That’s why these programs important,” Chattopadhyay told PTI.
“At least for the next century there is no such threat from the known asteroids that could cause massive casualties,” Karthick said, adding that this risk assessment, however, is based on the asteroids known to science so far.
Small asteroids always hit Earth, but they burn from the heat generated in the atmosphere. However, for large enough asteroids, that is not the case, as the outer core will burn up, but there will be enough mass left over to do damage.
The team will now observe Dimorphos using ground-based telescopes to confirm that the DART impact changed the asteroid’s orbit around Didymos.
Researchers expect the impact to shorten Dimorphos’ orbit by about 1 percent, or about 10 minutes; measuring exactly how much the asteroid was deflected is one of the main goals of the full test.
“After the impact, the team will observe Dimorphos using ground-based telescopes to confirm that the impact of DART changed the asteroid’s orbit around Didymos,” Karthick said.
“The expected output of the impact is to shorten Dimorphos’ orbit by about 1 percent or about 10 minutes. One of the main goals is to measure the deflection of the asteroid’s orbit,” he added.
Chattopadhyay said, however, whether the mission was able to deflect the asteroid’s orbit will not be known until all the data is collected.
“I would like to emphasize that our calculations and small-scale laboratory experiments show that it may work well.” he added
NASA has a multiple approach to monitoring Near Earth Asteroids (NEAs). The space agency started an observation program in 1998. Most discoveries are supported by telescopic measurements on the ground,
“For this we mainly use radars and lidars. Mostly they are systems on the ground, but our existing satellites in space are also used to image and track these objects,” the scientist added.
Lidar is a method of determining distance by aiming a laser at an object or surface and measuring the time for the reflected light.
“The DART mission is humanity’s first attempt to alter an asteroid’s trajectory by crashing a man-made object into it. Today’s successful impact is a major step forward in that direction.
“However, to know the ultimate success of this concept, we need to wait a few more years before a significant change in the trajectory will be clearly visible,” said Dibyendu Nandi, a space scientist at Indian Institutes of Science Education and Research, Kolkata.