On May 24, 1970, drilling began at the Kola Superdeep Bore. This project was an attempt to drill as deep as technologically possible. Several branching holes were drilled with the deepest reaching 7.6 miles into the Earth's crust. Several surprises were found on the way down. Seismic sonar mapping showed that seismic waves move faster below 2 miles and geologists expected a 'basement' layer where granite changes to basalt. They found instead the rock was changed by the heat and pressure. They also found the rock to be saturated with water. Another unexpected find was the discovery of microfossils of plankton from 4 miles down.

Ultimately, the largest surprise would be what would stop the drilling. They found the temperature rose much more quickly than expected. They thought they were going to encounter 100 °C rock at the 7 mile mark, but really found 180 °C temperatures. The rocks tended to act like a plastic at that pressure and temperature and the hole would fill in when the drill bits were pulled out to be replaced. Drilling stopped at 40,230 feet.

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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

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)

May 23^rd is American physicist John Bardeen's birthday. He was awarded the Nobel Prize in Physics on two different occasions. The first prize was in 1956 for being part of the team that developed the semiconductor transistor. The second was in 1972 for his role in formulating the BCS theory of superconductivity. Bardeen is one of four people to have won two different Nobel Prizes. Marie Curie, Linus Pauling and Frederick Sanger are the other three people who share this honor.

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