Meteor falling on Canada in 2021 may change humanity's view of solar system

Meteorites regularly fall towards the planet Earth, some of them are heated due to contact with the air, are worn out and disappear into the Earth's atmosphere, while another part reaches the surface of the Earth, at least 15-20 meteorites per day. The meteorite that fell in Canada last year, according to the authors of a study published in the scientific journal Nature Astronomy, could fundamentally change our view of the solar system, given where the meteorite reached Earth.

The meteorite fell in Canada on Feb. 22, 2021, at 6:23 a.m. local time. The moment of impact was captured by observatories, security systems, and many other video recording devices, including cameras that are part of the Global Fireball Observatory (GFO) network, which are specifically designed to find and capture such falling meteorites, allowing scientists to calculate their trajectory and place of origin.

The meteorite came from the Oort cloud

The meteorite is small, weighing only about 2 kg, and, judging by the way it cracked on contact with the air, it clearly consisted of stone. These types of meteorites usually come from the asteroid belt between Mars and Jupiter or somewhere closer to Earth. In this case, however, scientists determined that the meteorite traveled much longer. According to their calculations, it came from the Oort cloud, which is a huge collection of icy objects surrounding the solar system.

In their paper, a group of 13 scientists from different universities explain that current models of Oort cloud formation suggest that meteoric material began forming much closer to the Sun and from the remnants of the planet-building process in the solar system. Over time, the gravitational pull of Jupiter and the other giant planets returned it all back to where it is thought to have formed. However, according to this model, objects in the Oort cloud should consist of ice, not rock, like the Canadian meteorite.

"This discovery supports an entirely different model of the formation of the Solar System, one which backs the idea that significant amounts of rocky material co-exist with icy objects within the Oort cloud,” explained study author Denis Vida. “This result is not explained by the currently favoured solar system formation models. It’s a complete game changer."

You can see a model of the meteorite's trajectory in the video below.

Planet-killing asteroids

Scientists study asteroids that pose a potential threat to Earth on a daily basis so that they can predict at an early stage (later and to prevent a collision with the Earth) whether or not an asteroid could pose a serious threat to the Earth.

As part of such initiatives, NASA's DART probe recently collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. The goal of the DART mission was to determine if the asteroid's trajectory could be artificially altered to protect Earth and avoid clashing with asteroids in the future. Prior to the collision, Didymos orbited Dimorphos in 11 hours and 55 minutes. Scientists had expected that the collision would change the asteroid's orbit and change its rotation time by about 73 seconds, but the scientific experiment exceeded expectations: the time of one rotation of Dimorphos around Didymos was reduced by 32 minutes, and now it lasts 11 hours 23 minutes.

However, there are still some asteroids that are impossible to detect, because they hide, so to speak, under the Sun's rays, and it is difficult for telescopes to detect them. For example, modern space telescopes like the James Webb and the Hubble never are pointed at the Sun because the brightness of the star would burn out their sensitive optics. One such planet-killing asteroid, called 2022 AP7, was discovered this November.

Chinese researchers recently proposed deploying a new system of six spacecraft in Venus-like orbits that would aim to detect and warn of potentially threatening asteroids as quickly as possible.