Trivia

Hard

Which Of Our Solar System’s Dwarf Planets Was Discovered First?

Pluto
Ceres
Haumea
Eris
Ceres, as seen by the Dawn space probe.
Justin Cowart (NASA)/Flickr

Answer: Ceres

Although Pluto might be the most famous of the dwarf planets in our solar system—especially after the 2006 classification controversy that demoted it from “planet” to “dwarf planet”—it wasn’t the first one to be discovered.

The earliest observation of a dwarf planet dates to 1801 when it was discovered on New Year’s Day by Italian mathematician and astronomer Giuseppe Piazzi. Piazzi observed Ceres a total of 24 times, with the final time being February 11, 1801 when illness interrupted his observations. Based on those observations, he was unable to clearly determine if it was a planet or comet and opted for a more conservative estimate that it was a comet passing through our solar system. Later that same year, Carl Friedrich Gauss developed an efficient method of orbit calculation, which helped determine that it was in fact a dwarf planet.

In addition to being the first dwarf planet discovered in our solar system, Ceres has the distinction of being the smallest, which makes its place as first-discovered even more unique. The next dwarf planet, Pluto, wasn’t discovered until 1930. Nearly eighty years passed before any new dwarf planets were discovered, but between 2004 and 2005, three were added to the roster: Eris, Haumea, and Makemake. Why the long period between discoveries? Although scientists estimate there are dozens of dwarf planets in our solar system, their tiny size (Ceres, for example, is approximately 1.28 percent the size of the Moon) and enormous orbits (Eris takes nearly 560 years to orbit the Sun) make them particularly difficult to pin down and observe.

Trivia

Hard

What Beverage-related Item Was Invented Entirely By Accident?

Trivia

Hard

Before They Became World Renowned For Phones, Nokia Was Famous For?

Trivia

Hard

The 1956 Centurion, A Buick Concept Car, Had Which Of These Modern Features In It?

Trivia

Easy

Which Of These Categories Is Officially Banned By The Guinness Book Of World Records?

Trivia

Hard

The Screen-Independent Unit Used For Ensuring Exact Proportions Across Different Display Systems Is Called A?

Trivia

Hard

The Largest Known Freshwater Flood In All Of History Is Known As The?

Trivia

Very Hard

The Fastest Rotating Planet In The Solar System Is?

Trivia

Very Hard

The Largest Asteroid Impact Site In The World Is Located In?

Trivia

Very Hard

Which Game Console Was Marketed In Korea As The “Super Aladdin Boy”?

Trivia

Easy

The Largest Single Source Of Dust Pollution In The United States Is A?