x Abu Dhabi, UAEMonday 22 January 2018

Earth 1, Pluto 5

You can't keep a good planet - or dwarf planet, if you insist - down, as news of Pluto's fifth moon reminds us.

Scientists try to belittle Pluto, but the "dwarf planet" keeps getting back up. As if affronted by its downgrade (by earthlings, no less) from full planetary status, the icy celestial body still punches above its weight. On Wednesday, scientists announced that they had discovered Pluto's smallest moon. So that's Earth 1, Pluto 5. And there could be more.

"We're not finished searching yet," said Hal Weaver of Johns Hopkins University. The discovery of the fifth moon was made using the Hubble Space Telescope in preparation for the scheduled landing of a Nasa spacecraft, New Horizons, on Pluto in 2015.

In 2006, when the mission was launched, Pluto still basked in the glory of being the ninth planet from the sun. Later that year, killjoys at the International Astronomical Union, perhaps out of moon envy, demoted Pluto to the, quite frankly, insulting status of dwarf planet.

The decision did not go down well with many science fans. There were demonstrations calling for its reinstatement. New Mexico, home of Clyde William Tombaugh, the man who discovered Pluto, defiantly declared that March 13, 2007 was Pluto Planet Day. Not that Pluto is too bothered, we presume. It has an attraction that is all its own.