This pretty green glass formed as a result of the Trinity Nuclear Test near Alamogordo, New Mexico on July 16, 1945. Although it is radioactive, it is safe to handle and valued by collectors. Chemically, trinitite is mostly fused sand, or silicon dioxide. It is quartz with feldspar and various impurities.

While you might think Trinity or any atomic bomb would simply glass over the surface, it's theorized trinitite formed when sand was sucked up into the nuclear fireball and fell as molten glass, like extremely hot radioactive rain.

The desert sand formed green trinitite. Black trinitite contains iron from the metal tower constructed for the test, while extremely rare red trinitite gets its coloring from the actual device or the cables that led away from it. It's illegal to remove trinitite from the test site, but there is material in circulation that was taken before the prohibition.

May 17^th is Edward Jenner's birthday. Jenner was the English physician who noticed milk maids who had been infected with cowpox seemed to never contract the more serious disease, smallpox. Smallpox kills a third of the people who contract the disease, but if a person survives smallpox, they never catch it again. Variolation was the predominant smallpox treatment of the time. Variolation is when healthy people are exposed to a disease in hopes of giving them a milder (survivable) case of the disease. Between 2 and 3% of people exposed to variolation died.

Dr. Jenner tried a different route. He collected the pus from a cowpox sore on a milk maid and injected it into a young boy. He developed cowpox but quickly got over it. A couple weeks later Jenner exposed the boy to smallpox. He did not develop the disease. Jenner called his treatment a vaccine, from the Latin 'vaca', which means 'cow'. This treatment quickly became a standard treatment and is used for many different diseases.

Find out what else occurred on this day in science.

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Do you remember when I tried the instructions for making Glow in the Dark Mountain Dew™? The instructions given in the video were shown to be fake but that doesn't mean you can't duplicate the glowing bottle of soda. In fact, the real project is as easy and inexpensive as the fake project. I've made a video debunking the myth and then showing you how to really make a Mountain Dew bottle glow. Here's how you do it:

Glow in the Dark Mountain Dew Materials

• 20-oz bottle of Mountain Dew™ (but any bottle will work)
• glowstick or lightstick
• scissors or wirecutters
• dishwashing liquid (I used Dawn™)
• hydrogen peroxide
• baking soda

Make It Glow

• Pour out or drink all but a small volume of the soft drink (~1/4 inch). If your bottle is empty, add a little water.
• Add a squirt of dishwashing liquid.
• Use scissors or wirecutters to cut the glowstick. (I do not recommend using a steak knife, but if it's all you can find, it will work.)
• Empty the contents of the glowstick into the bottle. I used a pair of tiny inch-long sticks intended for use as earrings, so I just cut them in half and tossed them in the bottle. If the liquid won't flow you can snip the glowstick into pieces and just add the pieces to the bottle.
• Add 1-3 capfuls of hydrogen peroxide.
• Add a pinch of baking soda and immediately seal the bottle.
• Turn out the lights (if you haven't already) and vigorously shake the bottle.
• You probably guessed this, but I'll say it anyway... don't drink the contents of the bottle. Keep it out of reach of children or anyone else who might be tempted to drink the liquid.

Things to Know

• There's nothing special about Mountain Dew. In fact, you don't even need soda.
• You can make the bottle glow any color you like. Just use the appropriate color of glowstick.
• You don't absolutely need the peroxide or baking soda either. The project works if you add a little detergent and the contents of a broken glowstick to any near-empty 20-oz bottle.
• However, if you add the peroxide and baking soda, you get an immediate bright glow. Enjoy the glow while you can because the chemiluminescence reaction proceeds rapidly. If you use peroxide you will notice the light starting to fade within about half a minute.

How Lightsticks Work | Glowstick Colors
Photo: You can't drink glowing Mountain Dew, but that doesn't make it any less cool. One bottle is glowing Mountain Dew. The other is red-glowing Dr. Pepper. (Anne Helmenstine)

Napalm is the name given to any jellied form of gasoline or other flammable petroleum. It is used for circumstances where the liquid is too hard to apply or else won't stay where it is placed. One of the easiest forms of napalm to make is "Napalm B". This is a popular chemistry demonstration because it produces an interesting product and illustrates the synthesis and properties of a gelled sol. While it's practical for a school lab, it's also good for home school or as a home chemistry project because all you need is some gasoline (petrol) and polystyrene (e.g., Styrofam)... Try it