NASA’s test is set to make history on Monday, Sept. 26, and the LICIACube spacecraft’s “mini-camera” (short for Light Italian CubeSat for Asteroid Imaging) is warming up to capture the event, NASA said.

Check out the NASA event page here

Asteroids, more than mere potentially dangerous rocks, are themselves small geologically diverse worlds that tell the story of the origin of the Solar System, but which are still little known. The HERA probe, which will be launched after the DART mission, aims to explore these “unknown lands”, according to AFP, as quoted by Agerpres.

On Monday night into Tuesday, NASA’s DART mission will attempt to divert the asteroid from its path by encountering Dimorphos, a small “moon” orbiting the larger asteroid Didymos, located 11 million kilometers from Earth.

This experiment aims to reduce the orbit of a smaller asteroid around a larger one so that NASA engineers can find out if humanity can voluntarily change the trajectory of an asteroid that could threaten our planet.

“Such a two-asteroid system is an ideal test bed for planetary defense exercises, but it’s also a completely new environment,” summarized Ian Carnelli, HERA mission coordinator at the European Space Agency (ESA).

The European probe, named HERA after the Greek goddess of marriage, will launch in October 2024 and arrive at asteroid Dimorphos in 2026. His goal: to return to the “crime scene” to assess the effects of the DART strike.

Thus, the small asteroid deflection test will be fully documented thanks to the information collected by the instruments on board the HERA probe (video cameras, laser, high-resolution imaging, radar). The information obtained will help planetary defense specialists supplement with a high degree of reliability the computer models used to extrapolate the scenarios regarding the collision with the asteroid.

“New world”

“We need to know the nature and composition of asteroids because depending on the texture of the rock, they don’t pose the same danger,” said Bhavya Lal, NASA’s deputy administrator, at the International Aeronautical Congress in Paris this week. .

Scientists hope to be surprised by the results of these studies. “Because we know next to nothing” about these celestial bodies, said Patrick Michel, principal investigator of the HERA mission. “This is a new world that we are going to open,” he added.

This astrophysicist believes that asteroids “are not simple boring rocks from space, but fascinating and complex small geological worlds with craters, basins, rock fields, particle emissions.”

But researchers know very little about these areas because the gravity on their surface is very low compared to Earth’s: the behavior of matter there is “absolutely paradoxical, we can’t just rely on images to know how these asteroids behave.” , we have to touch them,” explained Patrick Michel.

One such example: a small explosion caused on the surface of asteroid Ryugu (discovered in 1999) created a 15-meter crater, much larger than predicted by computer simulations. Also, although the astrophysicists thought the asteroid rock was solid, “its surface surprisingly behaved like a liquid upon impact.”

Back in time

Binary systems such as Didymos and its companion Dimorphos make up about 15% of known asteroids and have not yet been studied.

With a diameter of 160 meters (the size of the Great Pyramid of Giza), Dimorphos will be the smallest asteroid ever explored by humans.

Instruments on board the HERA probe will try to unravel the mysteries of Dimorphos: shape, mass, chemical composition, internal structure, impact resistance, the shape of the crater caused by DART. At the end of the mission, the microsatellite will try to land on the surface of the asteroid to measure how it might ricochet.

Such unprecedented documentation will help astrophysicists travel back in time, as asteroids are excellent “bearers of the history of the solar system,” said Patrick Michel. These small telluric bodies have preserved the memory of the original composition of the Solar System and its planets, which were formed as a result of collisions.

“Today we live in an era when all solid surfaces in the solar system have craters. But to reconstruct the original scenario, we need to understand what happens when two bodies collide. Not in the laboratory, but on a real scale, thanks to a couple of DART-HERA missions,” the scientists explained.

The DART mission was launched in November 2021 from a base in California. After a 10-month journey, the US probe will collide with asteroid Dimorphos on Monday evening at 23:14 GMT at a speed of more than 20,000 km/h.

The spacecraft is no bigger than a car, and its target has a diameter of about 160 meters (half the height of the Eiffel Tower).

There is no reason to panic, because Dimorphos does not threaten the Earth in any way: its orbit around the Sun passes at a distance of 7 million kilometers from our planet.

The moment of collision is announced as spectacular and can be watched live on the website of the American space agency.

The goal is not to destroy the asteroid, but to deflect it slightly using the “Kinetic Impact Technique”.

Dimorphos is a satellite of the asteroid Didymos (diameter 780 meters), around which it makes a complete revolution in 11 hours and 55 minutes. The goal of the DART mission is to shorten Dimorphos’ orbit around Didymos by about 10 minutes.

This change can be measured from Earth by observing the change in brightness when a small asteroid passes in front of a larger asteroid.

To reach such a small target, the spacecraft will move in autonomous flight for the last four hours, like a homing missile.

Its Draco video camera will take the first last-minute images of the asteroid at a rate of one image per second, visible to Earth live with a delay of just 45 seconds.

In three minutes, the shoebox-sized LICIACube satellite, launched hours earlier by the DART probe, will fly within 55 kilometers of the asteroid to photograph the impact’s aftermath. The images will be sent back to Earth in the coming weeks and months.

The Hubble and James Webb space telescopes will also observe the event.

Very few of the known asteroids are considered potentially dangerous to Earth, and none of them will come close to our planet in the next 100 years.

“But I guarantee you that if you wait long enough, such a space object will appear,” said Thomas Zurbuchen, NASA’s science director.

Nearly 30,000 asteroids of all sizes have been cataloged near Earth (called geocruisers because their orbits cross Earth’s orbit). About 3,000 new asteroids are discovered every year.

According to scientists, almost all those with a diameter of more than 1 kilometer have already been discovered. But they also say that only 40% of asteroids larger than 140 meters in diameter are currently known to be capable of destroying entire regions on Earth.

If the DART probe misses its target, it will have enough fuel to make another attempt in two years.