In August 2003, Mars did make an unusually close approach to Earth; close that is in astronomical terms – 56 million kilometres away. That was the closest the Red Planet had been to Earth in 60,000 years but still far enough away to be of no concern. There was another close but more distant approach in 2005.
However, this does not stop the e-mail warnings from circulating that says Mars will be “close enough to be as big as the Moon with the naked eye.”
“The Red Planet is about to be Spectacular”
The e-mails usually carry a headline that says something like “The Red Planet is about to be Spectacular,” or “Two Moons on August 27.” People are invited to send the e-mail along to all their friends to make sure they don’t miss the amazing event: “NO ONE ALIVE TODAY WILL EVER SEE THIS AGAIN,” it warns in caps.
The original version of the e-mail that circulated before the 2003 event was reasonably accurate, but as with the game “Broken Telephone” stuff got distorted along the way. It is now so full of inaccuracies as to cause mirth among those who actually know a bit about space.
Astronomers Flooded With Enquiries
As the e-mail does its annual rounds in July and August, astronomers start to notice a spike in questions about the close encounter with Mars; so much so that NASA posted a page in 2005 alerting people to “Beware the Mars Hoax.”
“Here are the facts,” wrote NASA, “Earth and Mars are converging for a close encounter this year on October 30th at 0319 Universal Time. Distance: 69 million kilometres. To the unaided eye, Mars will look like a bright red star, a pinprick of light, certainly not as wide as the full Moon.
“Disappointed? Don’t be. If Mars did come close enough to rival the Moon, its gravity would alter Earth’s orbit and raise terrible tides.”
Science Behind the Rumour
BBC News Magazine writer Finlo Rohrer covered the story in an article on August 6, 2009. In the piece entitled "The perennial Mars hoax e-mail", Roher quotes Professor Colin Pillinger, of the Beagle 2 component of the Mars Express mission. He says the story keeps coming around “because the Earth goes around the Sun in 365 days and Mars goes around in 685 days. The Earth’s orbit is only very slightly elliptical. Mars is a very elliptical orbit.”
That means that every 26 months there is a close enough fly-by to get people excited, “And every 17 or so years there is a really close encounter.”
Not so in 2009. NASA notes that far from being close in August 2009, Mars will be 250 million kilometres distant; so far away as to be “completely absent” from the evening sky. Well, not quite. It will be visible to the naked eye in the morning sky, but it certainly won’t look like a second Moon and never will outside the realm of bad science fiction movies.
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