HONOLULU (KHON2) — A single day on Pluto is as long as 6.9 Earth days. Today, Feb. 18 is Pluto Day. You may ask yourself why Pluto has its own day since it is no longer considered a planet of our solar system.

Well, according to a new survey, sixty-six percent of respondents believe that Pluto needs to be restored as one of the planets of our Solar System.

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So, what is Pluto’s history here on Earth?

In 1902, Percival Lowell suggested there may be a 9th planet when he discovered that some of the planets, asteroid belts and comets seemed to have orbits that intersected with an unknown planet/object. But, it was not until 1930 that Pluto was discovered by Clyde Tombaugh.

The discovery threw astronomy for a loop, and astronomers had to recalculate how they understood both our solar system to be and the nature of the universe itself.

In 1978, Jim Christy discovered Charon, a body he believed to be Pluto’s moon. The size of Texas, this body casts the same amount of the Sun’s light onto Pluto as our moon casts on Earth.

However, in 2006, Pluto was declassified from a planet to a dwarf planet.

The discovery of several objects known as plutinos led to the discovery of the Kuiper Belt. This belt has possibly millions of icy bodies that have rotation patterns that are beyond the orbit of Neptune, and Pluto was in this belt.

The declassification of Pluto changed everything we understood about the outer planets of the Solar System. Textbooks had to be changed and algorithms updated.

But, the debate on whether Pluto should be reclassified as a planet has raged on for 17 years.

The New Horizons spacecraft made its way past Pluto in 2015. It discovered that Pluto has blue skies, spinning moons, red snow, a heart-shaped glacier the size of Texas and Oklahoma and a range of mountains as tall as the Rockies.

Since this flyby in 2015, NASA has discovered nine new things about Pluto that are unique.

1. Pluto has a heart.

This ‘heart’ drives the activity of the planet. The heart is a vast million-square-mile glacier made of nitrogen and is called Sputnik Planitia, The Sputnik Planitia forced Pluto to reorient so that the basin faces opposite of Charon.

According to James Tuttle, a planetary scientist and New Horizons team member at the Jet Propulsion Laboratory in Pasadena, California, this process is called a polar wander. This is when a planetary body changes its spin axis; this is usually due to some sort of large geological process.

2. Pluto’s surface may have a vast, liquid water ocean below.

While Charon is pulling and tugging on Pluto, the 2015 flyby also indicated that below Pluto’s icy crust is a large, water ocean that is causing a significant pull from Charon.

The ocean probably penetrated Sputnik Planitia from below. Astronomers believe that an object from Kuiper’s Belt collided with Pluto to create the large basin. This removed any thick crust and left the basin vulnerable to the water from below.

3. The possible liquid ocean may cause Pluto to be tectonically active.

Pluto has enormous faults that stretch for hundreds of miles and cut approximately 2.5 miles into the icy crust.

The significance of this is that the ocean below the surface continues to be in the process of freezing and creating new faults today. It also means there may be other bodies in the Kuiper Belt that also may have water oceans which expands the number of inhabitable bodies in our solar system may have.

4. Pluto may still have volcanic activity.

While on Earth there is hot, molten lava that spits, bubbles and erupts from underwater fissures, Pluto may have what is known as cryolava.

Cryolava is cold and slushy, and scientists believe that at some point this cryolava poured over the surface of Pluto at various points in its history.

5. Just like Earth, Pluto has glaciers that cut across its surface, even today.

There are not that many bodies in the solar system that have active glaciers, Earth, Mars and a handful of moons.

The 2015 flyby showed that east of Sputnik Planitia there are dozens of nitrogen-ice glaciers as well as water-ice glaciers. Because water is less dense than nitrogen, the water ice glaciers float on top of the nitrogen.

6. Sputnik contains heat convection cells.

This is Pluto’s most unique feature. There are no other planets that have polygonal shapes in the ice that churn on the surface of glaciers.

Astronomers said that they look like cells under a microscope. It is evidence that Pluto’s warm interior is escaping or venting underneath its glaciers. They form bubbles of upwelling and downwelling that look sort of like lava lamps.

7. A beating ‘heart’ controls Pluto’s atmosphere and climate.

This beating heart functions in much the same way Greenland and Antarctica do on Earth; it controls the climate.

Pluto’s heart-shaped Tombaugh Regio contains nitrogen ice, and it goes through a cycle every day. The ice sublimes to vapor during daylight hours; and during the frigid nighttime hours, it condenses back to the surface.

This also explains why Pluto has deserts.

8. There are dunes on Pluto.

The Sahara and Gobi deserts on Earth are made up of quartz, basalt and gypsum sands that are blown by, sometimes, gale-force winds. Astronomers believe that the dunes on Pluto are made up of sand-sized grains of methane ice carried by winds that blow at no more than 20 mph.

The water-ice mountains to the northwest fringes of the Sputnik glacier are probably what contributes to the small particles while the winds are provided by Pluto’s beating nitrogen ‘heart’.

9. There are virtually no small craters on either Pluto or Charon.

For years, astronomers have worked on the premise that large and small objects were jettisoned throughout the solar system as the universe was formed.

The fact that neither Pluto nor Charon have small craters shows scientists that the objects in the Kuiper Belt are not small. It also defies how scientists have come to understand how the universe was created and what happened when it was.

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According to NASA, “New Horizons transformed Pluto from a fuzzy telescopic dot, into a living world with stunning diversity and surprising complexity,” said Hal Weaver, New Horizons project scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.

So, what do you think? Is Pluto a planet or a dwarf planet?