On the 1st Jan 2021, we celebrated an end to a terrible year and the start to a new one, but also 220 years since the discovery of the often overlooked Dwarf Planet Ceres… 

The dwarf planet Ceres was discovered on New Years Day of 1801 by a Sicilian astronomer called Giuseppe Piazzi.

Guiseppe’s keen eye noted that the planet orbited the sun between Mars and Jupiter. Later, however, astronomers then discovered many things orbiting in the same region as Ceres, which prompted them to demote this dwarf planet and all the other objects to asteroid status. 

In 2006, there was a similar debate regarding Pluto, which made astronomers redefine the meaning of a planet.

Ceres rose like a Phoenix; reclassified again as a dwarf planet, along with the more famous Pluto who tends to get all the headlines. 

Even though Ceres is the smallest of the known dwarf planets, it remains the largest object in the asteroid belt.

It became the first dwarf planet to be orbited by a spacecraft from 2015 to 2018 when NASA through the Dawn Mission examined it more, unlocking several mysteries. 

Dwarf Planet Ceres
Dwarf Planet Ceres


The discovery of Ceres is mostly attributed to Giuseppe, however way back in the 1500s astronomer Johannes Kepler and Tycho Brahe also played a part. The latter was an enthusiastic night observer and a Danish nobleman. 

Kepler looked for any information he could find about the planets’ motion when he laid his hands on Tycho’s astronomical data. He mostly focused on Mars’ retrograde motion, which led him to develop Kepler’s three planetary motion laws, one of his more significant discoveries. 

While doing this, he spotted a surprisingly large empty area between Mars and Jupiter and asserted that there was something in the gap based on his theories of how regular planets move and orbit. 

He thought it was an undiscovered planet, a thought supported by his writing ‘Between Jupiter and Mars, I place a planet.’

It turned out that he was not the only observer who spotted this gap; Johann Titus laid the foundation to the Titus-Bode Law by stating a relationship between the orbital distances of the planets and the sun and also focused upon this large seeming void. 

These theories were further strengthened when in 1781, William Herschel discovered a new planet, we now call it Uranus.  

What sparked even more interest is that the distance to the sun aligned closely with the calculations provided by Titus-Bode Law.

A search then started, and by the end of the 18th century, a team of astronomers called the Celestial Police was founded to explore the gap between Mars and Jupiter. 

Giuseppe was supposed to be a member, but as it turned out, he had already discovered the planet before the Celestial Police extended him an invitation. He beat them to the find. 

Dwarf Planet Ceres Surface
The Surface on Dwarf Planet Ceres


Piazzi thought that the small spot he saw was a mere dim star, which was not part of his chart. However, when he made a closer observation, he found the object had moved.   

He couldn’t further observe the object in the few nights that followed due to illness and bad weather. Still, by January 24, 1801, Piazzi established that the object was a member of the solar system by tracking its motion and calculating its distance. 

This was the discovery of the missing planet, and Piazzi named it Ceres, a name given to the Roman goddess of agriculture, fertility, and harvest.

Other astronomers then started to discover new bodies around Ceres, which led Heinrich Olbers, a German Physician and astronomer, to discover the asteroids Pallas and Vests in 1802 and 1807 consecutively. 

However, when Neptune was discovered in 1846, the Titus-Bode Law, which had helped in Ceres’s discovery, was shown to be inaccurate and is no longer used today.  

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