Astronomers have revealed the most detailed map of asteroid Psyche so far

Astronomers have produced the most detailed map yet of the surface of 16-Psyche, an asteroid that scientists believe could hold clues to how planets formed in our solar system. according to paper Published in the Journal of Geophysical Research, 16-Psyche has a very diverse surface of mineral, sand, and rock suggesting that its history could include mineral eruptions, as well as collisions with other celestial bodies. The asteroid is the focus of NASA’s Psyche mission, which will be launched later this year.

as we are I mentioned earlier16 psychic M-type asteroid. (meaning it has a high metal content) orbits the sun in the main asteroid belt, unusually resembling a potato. The long-favored hypothesis is that Psyche is the exposed mineral core of a protoplanet (a minor planet) from the early days of our solar system, with its crust and mantle stripped by collisions (or multiple collisions) with other objects. In recent years, scientists have concluded that estimates of mass and density do not correspond to All-metal residue. Instead, it is likely to be a complex mixture of minerals and silicates.

Alternatively, the asteroid may have once been the original body of a certain class of stony and iron meteorites, those that shattered and reshaped to form a mixture of metal and silicates. or maybe something like 1 seriesa dwarf planet in the asteroid belt between the orbits of Mars and Jupiter—with the exception of 16 Psyche may have experienced a period of iron volcanoes during cooling, leaving highly enriched minerals in those volcanic centers.

Scientists have long suspected that metal cores lie as deep as terrestrial planets like Earth. But these cores are buried too far under the mantle and crusts of rock for researchers to detect. As the only mineral object ever discovered, Psyche provides an ideal opportunity to shed light on how the rocky planets in our Solar System (Earth, Mercury, Venus and Mars) formed. NASA agreed self mission In 2017, with the aim of sending a spacecraft to orbit the asteroid and collect important data about its properties.

Previous mapping efforts relied on measuring infrared light bouncing off the asteroid’s surface using various telescopes around the world. Last year, astronomers produced a much higher resolution Psyche surface map, based on 2019 observational data collected by all 66 radio antennas of the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile.

By combining all of these signals into a single artificial signal, the team achieved the resolution equivalent to a telescope with a diameter of 16 kilometers (10 miles) — about 20 miles per pixel. This view enabled them to resolve many of the compositional differences on the asteroid’s surface. Use this to create a file Heat emissions map From the surface of the asteroid with high accuracy 3D model self.

This latest map is based on hundreds of computer-simulated scenarios, each featuring a different mixture of surface material composition, taking into account the asteroid’s rotation. The team then compared those simulations to the actual heat emissions in the ALMA data to determine the most likely map of the 16-Psyche’s surface.

The results: the asteroid is rich in minerals, but its distribution across its surface varies. A similarly varied distribution of silicates indicates that 16-Psyche may have had a silicic-rich mantle. Moreover, the material at the bottom of the craters changes temperature faster than along the edge as the asteroid is spinning. The authors suggest that these craters may contain sediments (“pools”) of fine-grained sand. This is a bit surprising given 16-Psyche’s mass and stronger gravity, compared to smaller asteroids that contain fine-grained material.

“These data show that Psyche’s surface is heterogeneous, with marked differences in composition,” Simon Marchi said of the Southwest Research Institute, a Psyche task researcher who was not involved in the current study. “One of the primary goals of Psyche’s mission is to study the composition of the asteroid’s surface using gamma rays, a neutron spectrometer and a color imager. So, the possibility of compositional variations is something the Psyche Science team is eager to study further.”

DOI: Journal of Geophysical Research, 2022. 10.1029/2021JE007091/a> (About DOIs).