Break out your telescopes and scientific calculators! Space Day was created by Lockheed Martin Corporation in 1997 to motivate the youth of America to study math and science. This day was originally established as a one day event but because of overwhelming interest, Space Day became an annual event. In 2001, former astronaut and Senator John Glenn expanded Space Day to International Space Day. And ten years later, here we are with a round-up of geeky space-related stuff.

Almost exactly 50 years ago, on May 5, 1961, Alan Shepard was the first American (and second human after Yuri Gagarin’s orbit a few weeks prior) in space. Letters of Note has a nice letter from Shepard to his parents announcing his consideration for NASA’s “Man in Space” program. He says, “The entire program of space travel is a fascinating subject and I’m very pleased to be associated with it!” And he calls his parents “Mother and Daddy,” which is way retro and sweet.

This week NASA announced that their Gravity Probe B has confirmed two predictions of Albert Einstein’s general theory of relativity, specifically space-time warping and frame-dragging. This is a serious confirmation, with far-reaching implications for future astrophysics research.

Private space travel has also been in the news recently, as Virgin Galactic has completed its first “feathered” flight of SpaceShipTwo, the world’s first commercial spacecraft. If you’ve got a spare $200K lying about (perhaps in the sofa cushions?), you can book a flight when the program goes live. Don’t have that kind of cash? That’s okay–deposits start at just $20,000.

The Eta Aquarids meteor shower started Wednesday, but you can still catch it in the wee hours and at dusk today and tomorrow; it is particularly spectacular in the Southern Hemisphere.

For truly impressive images from space, I recommend sifting through the /r/spaceporn subreddit. Use them as wallpapers or print for DIY geek decor.

Do you love Steampunk and space? It’s not unlikely that some of you do, and you’re certainly not alone. Check out the Great Wetherell Refractor, a massive, riveted, brass-clad, functional Victorian telescope. Though the exterior is definitely a throw-back, the Wetherell uses modern electronic controls and coated optics.

Personally, I’ll probably spend the day watching Carl Sagan videos. Here’s one of everyone’s favorite astrophysicist / astronomer / cosmologist / geek TV host with a message for humanity. (Clip is from Cosmos episode 8, “Journeys in Space and Time.”)

If “doing stuff” isn’t your thing, just play some free online space games or something. :)

[sources: 1, 2, 3, 4, 5, 6] [images: 1, 2 ,3 , 4 ,5 ,6]