SCIENCE + TECHNOLOGY

Pluto gained a ‘heart’ after colliding with a planetary body

Apr 20, 2024, 7:00 AM

The New Horizons spacecraft took an image of Pluto's heart on July 14, 2015....

The New Horizons spacecraft took an image of Pluto's heart on July 14, 2015. (Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/NASA via CNN Newsource)

(Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/NASA via CNN Newsource)

Originally Published: 18 APR 24 15:26 ET
Updated: 19 APR 24 17:53 ET

Editor’s note: Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.

(CNN) — A huge heart-shaped feature on the surface of Pluto has intrigued astronomers since NASA’s New Horizons spacecraft captured it in a 2015 image. Now, researchers think they have solved the mystery of how the distinctive heart came to be — and it could reveal new clues about the dwarf planet’s origins.

Related: Jeff Caplan’s Minute of News: I’ll sit out on the next mission to Mars

The feature is called Tombaugh Regio in honor of astronomer Clyde Tombaugh, who discovered Pluto in 1930. But the heart is not all one element, scientists say. And for decades, details on Tombaugh Regio’s elevation, geological composition and distinct shape, as well as its highly reflective surface that is a brighter white than the rest of Pluto, have defied explanation.

A deep basin called Sputnik Planitia, which makes up the “left lobe” of the heart, is home to much of Pluto’s nitrogen ice.

The basin covers an area spanning 745 miles by 1,242 miles (1,200 kilometers by 2,000 kilometers), equivalent to about one-quarter of the United States, but it’s also 1.9 to 2.5 miles (3 to 4 kilometers) lower in elevation than the majority of the planet’s surface. Meanwhile, the right side of the heart also has a layer of nitrogen ice, but it’s much thinner.

Through new research on Sputnik Planitia, an international team of scientists has determined that a cataclysmic event created the heart. After an analysis involving numerical simulations, the researchers concluded a planetary body about 435 miles (700 kilometers) in diameter, or roughly twice the size of Switzerland from east to west, likely collided with Pluto early in the dwarf planet’s history.

The findings are part of a study about Pluto and its internal structure published Monday in the journal Nature Astronomy.

Recreating an ancient ‘splat’ on Pluto

Previously, the team studied unusual features across the solar system, such as those on the far side of the moon, that were likely created by collisions during the early, chaotic days of the system’s formation.

The researchers created the numerical simulations using smoothed particle hydrodynamics software, considered the basis for a wide range of planetary collision studies, to model different scenarios for potential impacts, velocities, angles and compositions of the theorized planetary body’s collision with Pluto.

The results showed that the planetary body likely crashed into Pluto at a slanted angle, rather than head-on.

“Pluto’s core is so cold that the (rocky body that collided with the dwarf planet) remained very hard and did not melt despite the heat of the impact, and thanks to the angle of impact and the low velocity, the core of the impactor did not sink into Pluto’s core, but remained intact as a splat on it,” said lead study author Dr. Harry Ballantyne, research associate at the University of Bern in Switzerland, in a statement.

But what happened to the planetary body after it smacked into Pluto?

“Somewhere beneath Sputnik is the remnant core of another massive body, that Pluto never quite digested,” said study coauthor Erik Asphaug, professor at the University of Arizona’s Lunar and Planetary Laboratory, in a statement.

The teardrop shape of Sputnik Planitia is a result of the frigidity of Pluto’s core, as well as the relatively low velocity of the impact itself, the team found. Other types of faster and more direct impacts would have created a more symmetrical shape.

“We are used to thinking of planetary collisions as incredibly intense events where you can ignore the details except for things like energy, momentum and density. But in the distant Solar System, velocities are so much slower, and solid ice is strong, so you have to be much more precise in your calculations,” Asphaug said. “That’s where the fun starts.”

Pluto’s murky origins

While studying the heart feature, the team also focused on the internal structure of Pluto. An impact early in Pluto’s history would have created a mass deficit, causing Sputnik Planitia to slowly migrate toward the dwarf planet’s north pole over time while the planet was still forming. This is due to the fact that the basin is less massive than its surroundings, according to the laws of physics, the researchers explained in the study.

However, Sputnik Planitia is near the dwarf planet’s equator.

Previous research has suggested that Pluto could have a subsurface ocean, and if so, the icy crust over the subsurface ocean would be thinner in the Sputnik Planitia region, creating a dense bulge of liquid water and causing a migration of mass toward the equator, the study authors said.

But the new study offers a different explanation for the feature’s location.

“In our simulations, all of Pluto’s primordial mantle is excavated by the impact, and as the impactor’s core material splats onto Pluto’s core, it creates a local mass excess that can explain the migration toward the equator without a subsurface ocean, or at most a very thin one,” said study coauthor Dr. Martin Jutzi, senior researcher of space research and planetary sciences at the University of Bern’s Physics Institute.

Kelsi Singer, a principal scientist at the Southwest Research Institute in Boulder, Colorado and co-deputy principal investigator on NASA’s New Horizons Mission, who was not involved with the study, said the authors did a thorough job of exploring the modeling and developing their hypotheses, though she would have liked to have seen “a closer tie to the geologic evidence.”

“For example, the authors suggest the southern portion of Sputnik Planitia is very deep, but much of the geologic evidence has been interpreted to point to the south being shallower than the north,” Singer said.

The researchers believe that the new theory regarding Pluto’s heart could shed more light on how the mysterious dwarf planet formed. Pluto’s origins have remained murky given that it exists on the edge of the solar system and has only been studied up close by the New Horizons mission.

“Pluto is a vast wonderland of unique and fascinating geology, so more creative hypotheses for explaining that geology are always helpful,” Singer said. “What would help to distinguish between different hypotheses is more information about the subsurface of Pluto. We can only get that by sending spacecraft mission to orbit Pluto, potentially with a radar that can peer through the ice.”

The-CNN-Wire
™ & © 2024 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.

We want to hear from you.

Have a story idea or tip? Send it to the KSL NewsRadio team here.

Science + Technology

The Utah Department of Transportation (UDOT), in collaboration with Utah State University (USU), su...

Diana Jones

Vertiports: The future is coming to Utah sooner rather than later

The Utah Department of Transportation, or UDOT, is pushing Utah into the future by taking steps to integrate vertiports around the state. But what are they? 

11 hours ago

The European Union is about to enact strict new rules to try to prevent misuse of Artificial Intell...

Simone Seikaly

New AI rules for the EU, but the loneliness remains

As the European Union adopts strict rules for Artificial Intelligence, some in America question if AI can replace loneliness.

3 days ago

a helicopter shown, vertiport demonstration tonight...

Sam Herrera

LISTEN: UDOT and USU to conduct vertiport demonstration

The Utah Department of Transportation and Utah State University will conduct the state's first vertiport demonstration Monday night.

4 days ago

The sun is rising with a flare over Korla, Xinjiang Uygur Autonomous Region, China, on May 10....

Brian Fung, CNN

Why tonight’s massive solar storm could disrupt communications and GPS systems

An unusual amount of solar activity due to a solar storm this week could disrupt some of the most important technologies society relies on.

14 days ago

Boeing's Starliner capsule sits atop an Atlas V rocket as it's rolled out to the launchpad on May 4...

Jackie Wattles, CNN

How to watch the first crewed flight of Boeing’s long-awaited Starliner spacecraft

Boeing’s spaceflight program may reach a milestone Monday night with the launch of its Starliner spacecraft.

19 days ago

This photo provided by NASA shows an Eta Aquarid meteor streaking over northern Georgia on April 29...

CHRISTINA LARSON, AP Science Writer

The Eta Aquarid meteor shower, debris of Halley’s comet, peaks this weekend. Here’s how to see it

The Eta Aquarid meteor shower, remnants of Halley's comet, peaks this weekend.

21 days ago

Sponsored Articles

a doctor putting her hand on the chest of her patient...

Intermountain Health

Intermountain nurse-midwives launch new gynecology access clinic

An access clinic launched by Intermountain nurse-midwives provides women with comprehensive gynecology care.

Young couple hugging while a realtor in a suit hands them keys in a new home...

Utah Association of Realtors

Buying a home this spring? Avoid these 5 costly pitfalls

By avoiding these pitfalls when buying a home this spring, you can ensure your investment will be long-lasting and secure.

a person dressed up as a nordic viking in a dragon boat resembling the bear lake monster...

Bear Lake Convention and Visitors Bureau

The Legend of the Bear Lake Monster

The Bear Lake monster has captivated people in the region for centuries, with tales that range from the believable to the bizarre.

...

Live Nation Concerts

All the artists coming to Utah First Credit Union Amphitheatre (formerly USANA Amp) this summer

Summer concerts are more than just entertainment; they’re a celebration of life, love, and connection.

Mother and cute toddler child in a little fancy wooden cottage, reading a book, drinking tea and en...

Visit Bear Lake

How to find the best winter lodging in Bear Lake, Utah

Winter lodging in Bear Lake can be more limited than in the summer, but with some careful planning you can easily book your next winter trip.

Happy family in winter clothing at the ski resort, winter time, watching at mountains in front of t...

Visit Bear Lake

Ski more for less: Affordable ski resorts near Bear Lake, Utah

Plan your perfect ski getaway in Bear Lake this winter, with pristine slopes, affordable tickets, and breathtaking scenery.

Pluto gained a ‘heart’ after colliding with a planetary body