On page C13 of today's New York Times is a quarter page ad for Google (it also appears at agoogleaday.com) which poses the following question: A Viking was the first to photograph us, but our existence was foretold in literature by a Swift astronomer. Who are we? Presumably, the point of the ad is to encourage people to use Google to find various arcane facts. If you have forgotten the appropriate references ("Swift astronomer" is the give-away for me), I have put the answer at the end of this email after several spaces. I wonder though about the claim that a Viking was the first to photograph the objects in question. I would have inserted the words "up close" after the word "us". Fletch ANSWER: Phobos and Deimos, the 2 moons of Mars. Swift astronomer refers to the visit to Laputa in the 3rd part of "Gulliver's Travels," while Viking refers to the Viking spacecraft. Incidentally, no telescope large enough to detect these moons existed until at least 100 years after Swift's books. I believe he just made up some numbers to show that he was familiar with the recent astronomical results, in this case Kepler's laws. In order for Kepler's 3rd law to be applicable to the moons of Mars, there would have to be at least 2 of them. Most of the visit to Laputa is a satiric take on science in general.