Perdita's Story: A game of hide-and-seek

My name means "lost". A bit unfair, because I have always known where I was.

Recovery image of Uranus' satellite S/1986 U-10, later named Perdita, taken with the Hubble Space Telescope in 2003. This image confirmed the existence of this moon, first reported in 1999 using Voyager 2 images from 1986. Credit: NASA/Space Telescope Science Institute

I first greeted you Earthlings through the camera of the Voyager 2 spacecraft in 1986, but it took you a bit to realize that I was there. More than ten years in fact! Obviously, by then I had already got tired of waiting, and was not very keen to show up in your pictures again.

So for some time you thought that the man who found me, Erich Kartoschka was his name, had made a mistake, or dreamed about me, or something... But in fact, I was just playing hide-and-seek with you. Eventually, the Hubble Space Telescope picked me in 2001, and the fun was over.

Where am I?

If you plan to visit me, you cannot get lost. Just head away from the Sun, past Saturn, and ask for the whereabouts of Uranus. (Yes, this is my dad. The coolest planet in the Solar System)

I am a small, dark moon, only 30 km wide. For comparison, your own moon is eleven times bigger than me! I orbit Uranus at about 76,000 km distance and with a speed of more than 31000 km/s. That's about five times closer than the Earth's Moon, and nearly nine times faster!

I have many siblings, 26 last time I counted them. My favourite sister is Belinda; I feel we truly resonate with each other's mind (and orbit). I also hang around a lot with Puck, and in general, with the whole of what you call Portia's group –Rosalind especially, but also Portia herself, Cressida, Desdemona, Juliet, Bianca and little Cupid. We have a lot of fun surfing between the planet rings!

Uranian moon-ring system. Credit: Ruslik0 (Wikimedia Commons)

Found, lost and found again

As I told you before, it was Voyager 2 who discovered me –although, as a matter of fact, it was more interested in my dad and siblings. But I was curious. We don't get so many visitors from Earth here after all! So I peeped out and voilà! There I was, just a faint speck in the image.

Voyager 2 image taken on 23 January 1986, with the positions of several Uranus moons indicated. Perdita is the moon S/1986 U-10 on the upper right. Credit: NASA/E. Kartoschka (University of Arizona)

To tell the truth, you need a lot of imagination to see me on that picture. It is not surprising that I passed unnoticed until 1999, and later still, simply, people could not find me anymore. So they thought I was a bluff. (Me? Really?)

It wasn't until 2003 when you Earthlings traced me back on images taken by the Hubble Space Telescope. And this time you paid me the attention I deserved. Well, I had made it easy for you... I was exactly where I was expected to be.

At first I got a very boring name. Honestly, how were people expected to remember something such as S/1986 U-10? Luckily, I was soon given my current name. Perdita. That means "lost" in Latin. A bit unfair, I thought, because I have always known where I was. However, with time, I have grown attached to it.

So Perdita I am. Nice to meet you all!

More on Perdita in this NASA page.