It was 15 years ago this month that once a certified solar system member. Pluto was kicked out of the club as it was downgraded to dwarf planet status. And a lot of the world is still pretty upset about it. Even Dr. Mike Brown, the man credited for it, accepts , accepts Indeed, his Twitter handle is PlutoKiller. Enough said. But why was Pluto kicked out of the solar system anyway? Were nine planets just one planet too many? Or was there a little more to it?
Darling of the solar system
The discovery of Pluto was announced with much excitement and fanfare back on February 18, 1930. Astronomer Clyde Tombaugh found it at the Lowell Observatory in Flagstaff, Arizona, with contributions from William H. Pickering. It was a time of intense planet-hunting; with explorers having mapped the continents on Earth, they turned instead to mapping the stars. And the possibility of a ninth planet in our solar system – known as Planet X – was the most sought-after prize. The Lowell Observatory had been hunting for the elusive world since 1909, with founder Percival Lowell dying empty-handed in 1916.
But Lowell had seen Pluto, although he didn’t realize it. Unknown to him, on March 19, 1915, his observatory had captured two faint images of Pluto. They weren’t the first to photograph the planet. At least 16 photos of Pluto have been identified that predate its official discovery. Pluto was there all along. They didn’t realize the gravity of what they were looking at. Then in 1930, 23-year-old astronomer, Clyde Tombaugh was tasked with taking photos of the night sky a few days apart so that a comparison could see which images were moving. “I looked in there [the telescope], and I spied it almost immediately, and a tremendous thrill came over me, and I almost shook,” he later said. If he was excited about the find, well, the world was over the moon.
God of the underworld is the prize of the skies.
As discoverers of the new planet, it was the Lowell Observatory’s privilege to give it a name. It opened it up to suggestions. More than 1000 names flooded in from across the globe. But one, from 11-year-old British girl Venetia Burney, was deemed the best. Venetia, from Oxford in England, had a keen interest in mythology. She suggested, therefore, Pluto, the Roman god of the underworld. She thought it suited a dark and cold world on the edge of the solar system. She received £5 as a reward (given by her grandfather), as well as, presumably, the immense satisfaction of having named the ninth planet in our little corner of the universe.
The name had one other advantage to it. The first two letters were the initials of Percival Lowell, who had spent so much of his life devoted to finding the planet. Venetia was still alive in 2006 when Pluto was told it was off the solar system team. Then Venetia Phair, a retired schoolteacher aged 87, wasn’t too upset at the planet’s demotion. “It’s interesting, isn’t it, that as they come to demote Pluto, so the interest in it seems to have grown,” she said in 2006. “At my age, I’ve been largely indifferent to [the debate] though I suppose I would prefer it to remain a planet.”
