Here are a couple of free periodic table wallpaper files for you. I'm working on a big element profile project which involved making periodic table cells. When the cells were all arranged on the monitor's desktop, they looked pretty cool, so here you go! A couple of notes... You've got your choice of white background or black background. The periodic table is optimized for 1920x1080 high definition. If your resolution is different the image will scale just fine.

Periodic Table Wallpaper - Black Background
Periodic Table Wallpaper - White Background

I know, I know... your grill is the cherished hearth-o-barbeque, but if you happen to have an old grill or a friend who has a grill but doesn't cook... or if you are a diehard pyro, you can make your own glass!

How does this work? Well, you can't make just any glass in your grill. It needs to be glass that has a relatively low melting point, such as soda lime glass. This is glass made from grinding silicon dioxide (sand) with borax, washing soda or lime. You're still going to need about 2000°F to make the glass, but if the ancients could do it, so can you. They would have used a fire with a bellows, but you can use a charcoal fire that is fed air using a vacuum cleaner.

If you want to try this project, you can get details and watch the video of home glassmaking in action at Popular Science's website, Popsci.com. Definitely watch the video. It's a spectacular demonstration, plus you'll see why most people will choose to use their grill for steaks rather than making glass. FIRE!

Colored Glass Chemistry | How to Make Water Glass

On May 22, 1969, NASA's Apollo 10 mission conducted the lunar module separation test and orbited the moon as a dress rehearsal for the Apollo 11 moon landing in July. Thomas Stafford and Eugene Cernan boarded the Snoopy lunar module and detatched from the command module and descended into a low lunar orbit. At closest approach, Snoopy came within 15 miles of where Apollo 11 would land. They reattached to the command module and returned to Earth.

This mission would have had to have been one of the most difficult missions to accomplish as an astronaut. They climbed aboard a fully equipped rocket, flew to the moon, got close to the landing point but purposely returned to the command module and came home. This seems about the same as getting in a car in New York City, driving to San Francisco's Fisherman's Wharf, seeing some great restaurants from the car as you drive by, returning to New York and telling the next crew all about the fish lunch specials you saw, how the car worked great and that there was plenty of parking.

Find out what else occurred on this day in science history.

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