A huge heart-shaped formation on its surface Pluto has piqued the interest of astronomers since NASA’s New Horizons spacecraft photographed it in 2015. Now, researchers believe they have solved the mystery of how this heart formed.
The formation is called Tombo area (Tombaugh Regio) in honor of astronomer Clyde Tombaugh, who discovered Pluto in 1930. But the details surrounding the Tombaugh Region’s elevation, geological makeup, and distinctive shape, as well as its highly reflective surface, which is whiter from the rest of Pluto, could not be explained.
A deep basin called Sputnik Plain (Sputnik Planitia), which forms the left side of the heart, hosts much of Pluto’s frozen nitrogen. It covers an area 1,200 x 2,000 kilometers, which is about a quarter of the size of the US, but is also 3 to 4 kilometers lower in elevation than the majority of the planet’s surface. The right side of the heart also has a layer of frozen nitrogen, but it is much thinner.
Through new research on the Sputnik Plain, an international team of scientists has determined that a cataclysmic event created the heart. After an analysis with numerical simulations, the researchers concluded that a planetary body about 700 kilometers in diameterlikely collided with Pluto early in the dwarf planet’s history.
Pluto’s “heart” (lower left) as photographed by the New Horizons spacecraft on July 24, 2015
NASA/JHUAPL/SwRI via AP
The findings are part of a study of Pluto and its internal structure published in the journal Nature Astronomy.
Simulations of conflict
The researchers created the numerical simulations using smoothed particle hydrodynamics (SPH) softwarein order to model different scenarios around the collision of the planetary body with Pluto.
The results showed that the planetary body probably collided with Pluto angled and not frontally.
“Pluto’s core is so cold that the rocky body that collided with it remained very hard and did not melt despite the heat of the collision. “Thanks to the collision angle and low speed, the core of the body did not sink into Pluto’s core, but remained intact as a splash on it,” said lead study author Dr. Harry Balladyne, from the University of Bern in Switzerland.
But what happened to the planetary body after it hit Pluto? “Somewhere below the Sputnik Plain is the remaining core of the massive body, which Pluto never quite digested.”
The teardrop shape of the Sputnik Plain is a result of the coldness of Pluto’s core, as well as the relatively low speed of the collision itself, the team found. Other types of faster and more direct collisions would have produced a more symmetrical shape.
With information from: Pluto gained a ‘heart’ after colliding with a planetary body by Ashley Strickland, CNN
