Did you get the Mars email?  The one going on about how Mars would be closer to the Earth than at any time in the past 60,000 years?  And how it would be as big as the full Moon?  Don’t worry, if you haven’t you probably will before much longer.  Here’s the scoop on the facts of the matter, from a real authority, Neil deGrasse Tyson.

From:The Haden Planetarium
by Neil deGrasse Tyson, 1 August 2010
Nearly everyone I know has received an e-mail about Mars from an anonymous source, but sent to them by friends who could not resist forwarding the message to their entire address book. The e-mail declares that toward the end of August, the planet Mars will be closer to Earth than it has in the past 60,000 years, thereby offering spectacular views of the Red Planet. The commentary proclaims, with liberal use of exclamation marks, that Mars will appear as bright as (or as large as) the full Moon in the night sky.

This Martian hyperbole dates from August of 2003, when the message was mildly factual, but vastly over-stated, leading people to believe Mars would be so bright that you might need sunglasses at night while driving. The rapid spread of this information was like some sort of brain info-virus, and led to one daily newspaper comic that showed Mars crashing into a home while the husband and wife were indoors, debating how close the planet will come.

Every 26 months, or so, Earth makes a close approach to Mars, as our smaller, swifter orbit overtakes Mars around the Sun. Because both the orbits of Mars and Earth are mildly elliptical, some close approaches between the two planets are closer than others, but by barely perceptible amounts.

So the proximity of Mars to Earth in 2003, while indeed closer than in the past 60,000 years, was nonetheless no more meaningful than me swimming a hundred yards out from the California coast (instead of my usual seventy yards) and then declaring to the world, I have never been this close to China before.

True, during close approaches, Mars gradually becomes one of the brightest objects in the night sky. But how bright? Slightly brighter than Jupiter’s average brightness. And not as bright as that of Venus. Yet nobody has ever issued warning statements about the visibility of Jupiter or Venus. In any case, Mars has had a close approach 3,000 times in recorded history, and, of course, billions of times in Earth’s history.

Now it’s time for you to send this antidote to all the infected people in your address book.

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