A new image of the asteroid probe provides clues to the formation of the planet



[ad_1]

Washington (AFP) – Photos taken by a probe of the size of a shoebox exploring the near-Earth asteroid, Ryugu, offer new clues to its composition, information that should help scientists to understand the formation of our solar system.

On October 3, 2018, the Japanese satellite Hayabusa2 dropped the Franco-German MASCOT mask (Mobile-German Asteroid Surface Scout). He fell free-fall from a height of 41 meters (135 feet) for six minutes before hitting the surface.

He then rebounded several times – reaching a height of 17 meters at the first rebound – before coming to a stop.

Ryugu is only 900 meters wide and its gravity is 66,500 times lower than that of the Earth. If MASCOT had been fitted with wheels, its forward movement would have brought it back into space.

Instead, he jumped to the surface using the minute amount of momentum generated by a metal swing arm attached to his square body, which weighed 10 kilograms (22 pounds).

In addition to temperature readings and other measurements, MASCOT returned a series of photographs showing that the asteroid is covered with two types of rocks and rocks: dark, rough rocks with friable surfaces resembling cauliflowers and shiny and smooth rocks.

"What's interesting is that Ryugu is the product of some kind of violent process," said Ralf Jaumann of the German Aerospace Center at AFP. He is the main author of an article describing the results, published Thursday in the journal Science.

Ryugu may be the child of two parent bodies that collided, separated, and were then collapsed together by gravity, according to the researchers.

Otherwise, it could have been struck by another body that created different internal temperature and pressure conditions, creating both types of material.

Many rocks contain small blue and red "inclusions" – a material trapped in the rock during its formation – much like a type of rare primordial meteorites found on Earth, called carbonaceous chondrites.

"This material is a primitive material – it's the very first material of the solar nebula," or the cloud of dust and interstellar gas that formed the planets of our system, Jaumann said.

Hayabusa2, who left Earth in 2014 and landed twice on the surface of the asteroid, most recently in July, will arrive home next year with samples to be analyzed in the laboratory.

MASCOT's observations provide, for the first time, information on the geological context of the material's origin, including how it is exposed to changes in temperature and its "aging" in space. .

"We do not know how the planets formed at first," Jaumann said.

"And to understand this, we must (we must) go to the small bodies, these primitive bodies, paramount in their history in their evolution, in order to understand the 10 to 100 million years of planetary formation."

– A dust mystery and a future threat? –

MASCOT also introduced scientists to a new mystery: its lack of fine particles, or interplanetary dust, that would normally accumulate after millions of years of atmospheric aging.

The paper offered theories but no definitive conclusion.

The dust could have fallen into tiny holes on the surface of Ryugu when the asteroid was allegedly hit by other bodies.

Alternatively, temperature changes could result in an electrostatic force that has expelled dust in the space. Or, water could have existed on Ryugu and its evaporation would have resulted in the smallest particles.

There is another reason to study asteroids: the survival of humanity could one day depend on it.

The orbit of Ryugu places it mainly between Earth and Mars. Although this is close, it should not put us in danger, but other asteroids could.

If their composition is similar to that of Ryugu, trying to eliminate them with a missile would probably break them into smaller rocks still directed towards the Earth.

One possibility would be to build a large reflective solar sail and place it on the surface of the asteroid, so that the solar radiation pressure gradually changes its course, said Jaumann.

Regardless of the strategy adopted, he and other astronomers say that it is clear that these little enigmatic bodies are of significant importance in our solar neighborhood.

[ad_2]

Source link