How did Pluto get its white heart?
When a piece of ice collides with an ice dwarf, it is interpreted artistically
Source: University of Bern, illustration by Thibaut Roger
Pluto has long lost its status as the ninth planet. But the strange bright spot on its surface remains a mystery. Now astrophysicists have found a cool explanation for this – and at the same time they have solved another question.
DrThe huge, bright core on Pluto's surface was likely the result of a collision with a piece of ice. This is the result of simulations conducted by an international research group, which were published in the journal Nature Astronomy. the Stady He also wonders whether there is actually an ocean beneath the surface of the dwarf planet.
In July 2015, the American space probe “New Horizons” flew near the dwarf planet located on the edge of our solar system after more than nine years of flight. Delivered High-resolution images and data from Pluto and its moons to Earth for the first time. The images showed a large, bright core on the surface of the ice dwarf. This structure was named “Tombo Reggio” after the American astronomer Clyde Tombo, who discovered Pluto almost 100 years ago.
An international group of astrophysicists led by Harry Ballantyne of the University of Bern has studied the mystery surrounding the formation and nature of Pluto's core. The team focused on Sputnik Planitia, the western, teardrop-shaped part of the structure. This part covers an area of 1,200 by 2,000 kilometers, which is equivalent to a quarter of the area of Europe, and is three to four kilometers deeper than most of the celestial body's surface.
“Sputnik Planitia’s bright appearance is due to the fact that it is mostly filled with white nitrogen ice,” lead author Ballantyne was quoted as saying in a statement from the university. The ice moves and the current travels, so that the surface becomes constantly smooth. “This nitrogen likely accumulated quickly after the impact due to the low altitude,” explains Ballantyne.
This image clearly shows the heart-shaped structure on Pluto's surface
Source: NASA/Johns Hopkins University Applied Physics Laboratory/Southwestern Research Institute
Using simulation software, the team recreated how Sputnik Planitia was created. In this way, astrophysicists calculated that this part of the core was probably the result of a planetary body with a diameter of about 700 kilometers colliding with the surface at low speed.
The rock is probably mainly ice with a rocky core. “The elongated shape of Sputnik Planitia strongly suggests that it was not a direct frontal impact, but rather an oblique impact,” explains co-author Martin Goetze from the University of Bern.
“Pluto's core is so cold that the rocks remained very solid and did not melt despite the heat of the impact,” Ballantyne adds. Thanks to the oblique angle of impact and the low speed, the impactor's core did not sink into Pluto's heart, but rather remained above it. “Somewhere beneath Sputnik lies the remains of the core of another massive object that Pluto never fully digested,” adds co-author Eric Asfaugh of the University of Arizona.
As the authors note, their study also sheds new light on the internal structure of the ice dwarf, which has been dead for nearly 20 years. condition Lost as a planet. It is currently assumed that Pluto, like other celestial bodies in the outer solar system, has an underground ocean of liquid water.
Simulations now also allow the view that there is only a very thin subsurface ocean or no subsurface ocean at all.
“Alcohol buff. Troublemaker. Introvert. Student. Social media lover. Web ninja. Bacon fan. Reader.”
More Stories
Zelinger defends cooperation with China
Science – a research initiative that brings millions to the University of Mainz – Education
Do you want to work at NASA? These are the 43 citizen science projects that want to do real science