Sunday, January 30, 2011

The Magnetar Credit Card Swipe

Ned Flanders' credit card doesn't satisfy the Luhn checksum,
but could probably still be erased by a magnetar. 
Hello, Internet!  Today I'd like to talk about the Magnetar Credit Card Swipe.  Sounds like some sinister short on a derivatives deal, doesn't it?  Well, no need to worry, we don't deal with scary things like that here.  Instead, we are going to talk about a super-magnetized neutron star speeding past Earth.

A while ago I heard that a magnetar can erase all the world's credit cards from half the distance to the moon.  I did a little research and it seems like this is the go-to "fun fact" about magnetars.  Almost every time they are brought up in a popular science article, their credit card-erasing prowess is sure to get a mention.  So let's check it out!

Thursday, January 27, 2011

Falling Ice

It's been a while since I posted anything, much to my shame.  Hopefully this post marks a change in that streak.  Today I'm going to consider a very practical application of all this physics stuff.  One of my housemates parks his car on the side of the house, with the front of the car facing the house.  Living in Ithaca, NY, the weather has been the usual cold and snowy, like the rest of the northeast USA this winter. Yet, early last week, we had some unusually warm weather, in the 30s (fahrenheit).  A few days later, my housemate went out to his car, and discovered that falling chunks of ice had broken his windshield!  Now, to be clear here, I'm not talking about icicles, I'm talking about large, block-like, chunks.  My best guess is that during the warm days, snow on the roof turned into chunks of ice, and slid off the roof.  The question I'm going to try to answer today is: How far from the house could these chunks possibly land?  Put another way, what I want to know is, how far from the house would we have to park our cars to not risk broken windshields from falling ice?

Thursday, January 13, 2011


Over break I went out with a buddy of mine and played some darts. This got me to thinking, where exactly should someone aim in order to get the largest expected number of points?

Monday, January 3, 2011

Holiday Hidden Message Revealed

Here we present the solution to the Holiday Code (original post here).  The content of the message is from the creepy looking gentleman to the left, Henry Wadsworth Longfellow.  He is perhaps most famous for writing the poem, "Paul Revere's Ride."

I have taken another one of his popular poems, "Christmas Bells," and hidden its first verse in a huge mess of random letters.  The message:

"I heard the bells on Christmas Day
Their old, familiar carols play,
And wild and sweet
The words repeat 
Of peace on earth, good-will to men!"  

Sounds pretty pleasant at the start.  But it was written at the height of the Civil War and it gets pretty heavy towards the end.  Longfellow was an ardent abolitionist and most of his poems contain allusions to the plight of slaves.  He was also close friends with Senator Charles Sumner, whose own fiery oratory and opposition to slavery famously put him on the wrong side of a Southern cane.