The March 19th “Supermoon” = Hardly Super

Sometimes there’s no telling what the world will get excited about. Amid the ongoing catastrophe in Japan, the Libyan and Yemeni crises and everything else, the news media and half the internet, it seems, are eagerly awaiting Saturday’s “supermoon.” It’s being billed as the closest, biggest, and brightest full Moon in 19 years.

It’s true. The Moon is full on March 19th right about when it’s at perigee, its closest to Earth in its monthly orbit. And not all perigees are precisely the same. This one is a trace closer than usual.

But not by enough to notice.

There’s something that many people (and too much of the news media) never seem to grasp: When it comes to science stories, if you don’t know it in numbers, you don’t know it at all.

How much bigger is this month’s full Moon? Here’s the number. It’s just 2% bigger than the full Moons of last month and next month. That’s one part in fifty. You couldn’t tell the difference if you put them side by side…

The takeaway message from this episode? Astronomy stories inspire people to look up and consider the larger universe, but they can also educate in practical ways for getting through life. The “supermoon” flap is a harmless bit of hype. But when your relatives start sending you frantic chain letters about the Japanese nuclear fallout starting to “pound the West Coast,” like one blog post I’ve already seen going around, remember what you read here.

Look at the numbers for the radiation reaching the West Coast. You’ll see that it’s trivial compared to the natural background radiation that everyone receives every day of their lives.

So don’t let anyone tell you that you can’t learn anything practical from astronomy. Send your frantic aunt this article, and tell her why she should quit with the dumb chain letters already.


Blue moon to light the sky this New Year’s Eve

If you have anything ridiculously ambitious or wondrously farfetched you’d like to achieve in life, then we’d strongly suggest aiming to achieve such goals this coming New Year’s Eve – a date on the calendar expected to be marked by a distinct ‘blue moon’.

Beyond the obvious ‘once in a lifetime’ adage, stargazing astronomers have revealed that 2010 will be ushered in alongside a genuine blue moon, which, while not nearly as rare as you may think (usually about once every 30 months), will be the first to illuminate the night sky on New Year’s Eve since 1990.

According to astronomer David Reneke of Australasian Science magazine, the next New Year’s Eve blue moon isn’t likely to happen until 2028.

To historians enjoying astronomy, the last century cast a “blue moon” into existence whenever there were two full moons in a single month.

For me, as I have through the happiest years of my life – I celebrate my wife’s birthday every New Year’s Eve.