I heart Pluto day!

Yesterday was I Heart Pluto day! On February 18 marks the 95th anniversary of Pluto’s discovery. Today we will be talking about facts about Pluto!

Pluto history

It all happened in 1930 a young man called Clyde Tombaugh fresh off his farm in Kansas discovered Pluto. He was fascinated with the night sky, spending many many many hours scanning the sky to find a moving planet "X". He built telescopes with random items around the farm. One day he sent a letter of drawings of Mars and Jupiter to Lowell observatory. They were looking for staff so right then he was hired. The director said in a letter, 'We're just recommencing the search for a ninth planet, and we need somebody to help with it. It looks like you know what you're talking about, so why don’t you come work for us?"

He used a trick called "blink comparison," making him search through many photos for a hidden moving planet. Blink comparison basically means looking at photographs of the same part of the sky on different nights and then quickly switching between the two images to find any moving objects. Every day he huddled himself in the cold and winter to take these pictures and FINALLY on February 18, 1930, he saw the one dot he had been searching for!

A ninth planet, Pluto, had been discovered...

Then again in 1978 Jim Christie and Bob Harrington were analyzing new photos. They found a random bump on Pluto then again after a year boom the bump is gone?! This was evidence that Pluto had a moon! A moon named Charon after Greek mythology, Charon served as the ferryman in the underworld. Charon was almost the size of Pluto! It was so big that both Pluto and Charon spin around each other, like a double dwarf planet combo! Later on, the Hubble telescope found two other dim moons.

Planet or Not?

Pluto was our ninth planet for a long time, in 2006, Pluto's status was re-checked by the International Astronomical Union (IAU), they changed Pluto from a planet to a dwarf planet along with its other friends/objects in the solar system that are similar to Pluto: Ceres, Makemake, Haumea, and Eris.

A planet is only:

1. Orbit the sun
2. Be a spheroid under the force of its own gravity
3. Clear its orbit of other debris

But! Pluto fails the third criterion!

It's in the Kuiper belt, the Kuiper is like a doughnut bulging out. It has many cold rocks beyond Neptune. Pluto's path overlaps with objects in the Kuiper Belt making it not a clear path.

The Star of Dwarf Planets

Studying Pluto is quite the challenge it takes the biggest telescopes and the most advanced instruments! Even for the HUBBLE SPACE TELESCOPE, it's tough! We could really get just a tiny dot in telescopes BUT later on, in 2015, NASA's New Horizons spacecraft gave us our first detailed picture of the one and only, Pluto. Showing many mountains and valleys made from ice and hey! It has the iconic heart shape known as Tombaugh Regi.

Pluto, named after the god of the underworld in Roman mythology, has a year that lasts 248 Earth years. Pluto has 5 moons orbiting around it, the largest moon is Charon. It is so big that Pluto and Charon orbit each other like a double planet. Pluto’s other four moons: Hydra, Nix, Kerberos, and Styx, are much smaller than Charon. It has a thin atmosphere of nitrogen, methane, and carbon monoxide making a blue tint and different layers of haze. It is about -223 degrees Celsius, far too cold! It orbits far out in the Kuiper belt in an oval-shaped path. The Kuiper belt has many cold rocks and in the Kuiper belt, Pluto is known as the "King of the Kuiper Belt," because it's the largest object there.

The year of Pluto 2015

In 2001 the New Horizon mission was on! On January 19, 2006, NASA launched a robot spacecraft on a very long journey to the Kuiper Belt! It was the first mission to the Kuiper belt. We finally got to visit Pluto, Charon, and the Kuiper Belt on July 14, 2015! Still, the New Horizon is studying other rocky objects in the Kuiper Belt to this day.

Every year, the Lowell Observatory hosts the I Heart Pluto Festival to celebrate the discovery of Pluto!