Pluto Archives

April 21, 2021April 21, 2021 by Nancy Atkinson

New Horizons is Now 50 Astronomical Units Away From the Sun

Currently exploring the Kuiper Belt, New Horizons is just one of five spacecraft to reach beyond 50 astronomical units, on its way out of the solar system and, eventually, into interstellar space. (Credit: NASA/Johns Hopkins APL/Southwest Research Institute)

As the New Horizons spacecraft hurtles out towards interstellar space, it has now reached an historical milestone. On April 17, 2021, New Horizons passed 50 astronomical units, or 50 times Earth’s distance from the Sun. It is just the 5^th spacecraft to reach that distance, joining the Voyagers 1 and 2 and the Pioneers 10 and 11.

October 16, 2020October 16, 2020 by Evan Gough

Pluto has Snowcapped Mountains, But Why?

On the left, the region of "Cthulhu" near the equator of Pluto and on the right, the Alps on Earth. Two identical landscapes, created by very different processes. Image Credit: © NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute © Thomas Pesquet / ESA

We can thank NASA’s New Horizons spacecraft for opening our eyes up to Pluto’s complexity. On July 14th, 2015, the spacecraft came within 12,500 km (7,800 mi) of the dwarf planet. During the flyby, New Horizons was able to characterize Pluto’s atmosphere and its surface.

Among the things New Horizons saw was a region of snowcapped mountains.

June 23, 2020June 23, 2020 by Evan Gough

Pluto and Other Kuiper Belt Objects Started Out With Water Oceans, and Have Been Slowly Freezing Solid for Billions of Years

Far left: Pluto and it's heart-shaped feature called “Tombaugh Regio” in honor of astronomer Clyde Tombaugh, who discovered the dwarf planet. The bright expanse of the western lobe of Pluto’s “heart” is informally called Sputnik Planum. Above left: Pluto’s surface sports a remarkable range of landforms that have their own distinct colors, telling a complex geological and climatological story. Credit: Courtesy NASA / JHUAPL / SwRI Table of Contents page 2015 Annual Report Division: (15)

It seems unlikely that an ocean could persist on a world that never gets closer than 30 astronomical units from the Sun. But that’s the case with Pluto. Evidence shows that it has a sub-surface ocean between 100 to 180 km thick, at the boundary between the core and the mantle. Other Kuiper Belt Objects may be similar.

But time might be running out for these buried oceans, which will one day turn to ice.

May 14, 2020May 14, 2020 by Evan Gough

Astronomers Continue to Analyze Pluto’s Atmosphere

This image of Pluto taken by the New Horizons spacecraft shows the blue color of Pluto's high-altitude haze. Image: NASA/New Horizons.

When NASA’s New Horizons spacecraft flew past Pluto, studying the atmosphere was a key scientific objective. Most of what we know about the ice dwarf came from that flyby. That happened in July 2015, but it took over 15 months to send all the data home, and it’s taking even longer to analyze it.

February 6, 2020February 6, 2020 by Evan Gough

There Are Winds Blowing On Pluto, Driven by Frozen Nitrogen

NASA's New Horizons spacecraft captured this image of Sputnik Planitia — a glacial expanse rich in nitrogen, carbon monoxide and methane ices — that forms the left lobe of a heart-shaped feature on Pluto’s surface. SwRI scientists studied the dwarf planet’s nitrogen and carbon monoxide composition to develop a new theory for its formation. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Earth and Pluto don’t have much in common. Earth is a vibrant, living world, whereas Pluto is cold, distant and lifeless. But one thing they do have in common is nitrogen. Earth’s atmosphere is about 78% nitrogen, and Pluto’s primary atmospheric constituent is also nitrogen, although the exact percentage is unclear.

On Pluto, where the surface temperature is about 42 Kelvin (-231 Celsius) most of that nitrogen is frozen. A new study says that Pluto’s frozen nitrogen drives the planet’s winds, and shapes its feature surfaces.

November 1, 2019November 1, 2019 by Evan Gough

NASA is Now Considering a Pluto Orbiter Mission

NASA’s New Horizons mission taught us a lot about Pluto, the ice dwarf planet. But the spacecraft sped past Pluto so quickly, we only got high-resolution images of one side of the planet, the so-called “encounter side.” New Horizons gave us a big leap in understanding, but in a way, it asked more questions than it answered.

The next step is clearly an orbiter, and now NASA is starting to seriously consider one.

October 25, 2019October 25, 2019 by Evan Gough

New Horizons Team Pieces Together the Best Images They Have of Pluto’s Far Side

New Horizon's July 2015 flyby of Pluto captured this iconic image of the heart-shaped region called Tombaugh Regio. Credit: NASA/JHUAPL/SwRI.

Pluto was discovered in 1930 by astronomer Clyde Tombaugh. For decades, not much detail was known about the erstwhile planet. We assumed it was a frozen, dormant world.

August 9, 2019August 9, 2019 by Evan Gough

A Bunch of New Names for Pluto’s Surface Features Were Just Approved

14 of Pluto's surface features have new official names now. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Ross Beyer

Pluto is getting some new names. In the past, prior to the New Horizons mission, there wasn’t much to name. But now that that spacecraft has flew past Pluto and observed it up close, there’s some features that need naming.

Now the IAU (International Astronomical Union) has approved a new set of names for 14 of the dwarf planet’s surface features.

May 23, 2019May 23, 2019 by Matt Williams

An Insulating Layer of Gas Could Keep a Liquid Ocean Inside Pluto

New Horizons view of Pluto — The heart-shaped region of Pluto's surface was formed at least in part by a cataclysmic "splat," scientists say. (Credit: NASA / JHUAPL / SwRI)

In July of 2015, NASA’s New Horizons mission made history by becoming the first spacecraft to ever conduct a flyby with Pluto. In addition to providing the world with the first up-close images of this distant world, New Horizons‘ suite of scientific instruments also provided scientists with a wealth of information about Pluto – including its surface features, composition, and atmosphere.

The images the spacecraft took of the surface also revealed unexpected features like the basin named Sputnik Planitia – which scientists saw as an indication of a subsurface ocean. In a new study led by researchers from the University of Hokkaido, the presence of a thin layer of clathrate hydrates at the base of Pluto’s ice shell would ensure that this world could support an ocean.

March 9, 2019March 9, 2019 by Matt Williams

Pluto and Charon Don’t Have Enough Small Craters

New Horizons image of the small craters on Pluto's moon Charon. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

In 2015, the New Horizons mission became the first robotic spacecraft to conduct a flyby of Pluto. In so doing, the probe managed to capture stunning photos and valuable data on what was once considered to be the ninth planet of the Solar System (and to some, still is) and its moons. Years later, scientists are still poring over the data to see what else they can learn about the Pluto-Charon system.

For instance, the mission science team at the Southwest Research Institute (SwRI) recently made an interesting discovery about Pluto and Charon. Based on images acquired by the New Horizons spacecraft of some small craters on their surfaces, the team indirectly confirmed something about the Kuiper Belt could have serious implications for our models of Solar System formation.