Friday, March 7, 2014

Five-Sided Ice Crystals

When you picture a snowflake, you probably envision a six-sided shape. Because of the angle of the bonds between hydrogen and oxygen in water, that geometry is greatly favored over other forms. However, snowflakes come in other shapes besides hexagons. For example, there is pentagonal ice. A team of scientists led by the London Centre for Nanotechnology (LCN) discovered a linear chain built from ice pentagons. The chains were formed on a nanoscale across a flat copper surface. Scanning tunneling microscopy was used to image them. While you shouldn't expect to see pentagonal snowflakes any time soon, the research might be used to find new materials to initiate nucleation of water to form clouds and precipitation and also to better-understand how these processes occur naturally.

What Do Metal Crystals Look Like?

Some of the most beautiful crystals are made entirely of pure metal elements. For example, this dainty crystal is a crystal of pure gold. Metal crystals often have lacy or interesting geometric structures. You can view other types of metal crystals in the Metal Crystal Photo Gallery.

This Day in Science History - March 6 - Joseph von Fraunhofer

March 6th is Joseph von Fraunhofer's birthday. Fraunhofer was a German physicist who discovered thin dark bands while investigating the sun's spectrum. Bunsen and Kirchhoff later discovered that they corresponded to the wavelengths of the absorption of common elements like hydrogen, helium and iron. The energy from the sun would pass through the upper layers of the sun and get absorbed, causing the dark lines. These lines are now known as "Fraunhofer lines" in his honor.

Aurora Borealis in Alaska

I'm in the airport awaiting a flight to Alaska to see the sights and try out some science projects that only work when it's really cold. Of course, at the top of my list of things to do is to watch and photograph the aurora borealis. March is a perfect month to view the lights in Alaska because the nights are still long and often clear and for some reason, the aurora seems to do well close to the equinox. We're also near the peak of the solar cycle, so chances are good I'll enjoy the northern lights.

I'll be posting pictures of my adventures, so stay tuned!

Sunday, March 2, 2014

This Day in Science History - March 2 - Heinrich Olbers

March 2nd marks the passing of Heinrich Olbers. Olbers was a German physician and amateur astronomer who devised a simple method to calculate the orbits of comets and discovered two large asteroids, Vesta and Pallas. He also believed the asteroids were remnants of a wrecked planet that orbited the Sun between Mars and Jupiter.

Olbers is also known for the question "Why is the night sky dark?". If you assume that the universe is infinite and filled with stars, you should see light from stars in all directions and the night sky should be as bright as daylight. As we all know, the night sky dark with many points of light.

This question is known as Olbers' Paradox and had no simple answer. The Big Bang Theory tries to answer the question by stating there is a finite number of stars and the universe is constantly expanding.

1972 - NASA launches the Pioneer 10 space probe.

Pioneer spacecraftNASA
Pioneer 10 was the first spacecraft to pass through the asteroid belt and take direct observations of the planet Jupiter. It also became the first to leave our solar system.

Make Glowing Hands

Are you seeking a ghostly blue glow, for your hands or other skin? It's easy to get a vivid blue glow using either of two common household chemicals.
 Give your hands or any other skin a ghostly blue glow! It's easy to do.

Glowing Hands - Method #1

Rub petroleum jelly on your hands. They will glow bright blue under a black light. This is a great way to make any skin glow, including skin on your face. Just be sure to avoid getting petroleum jelly in your eyes, since it will sting.

Glowing Hands - Method #2

Rub laundry detergent on your hands. They will glow very bright blue under a black light. It's not actually the detergent that makes your skin fluoresce, so you won't get the same effect from dishwashing detergent or most soaps. The brightening agent added to prevent clothes from appearing dull and gray is the active ingredient. Laundry detergent may irritate your skin, so you may wish to put on plastic gloves before coating your hands with the detergent. Rinse your hands under water when you are done, to remove the detergent.

How to Remove Iodine from Water

Answer: According to Lenntech, a water treatment and purification company, it's easy to remove iodine from water. Simply pass the water over activated carbon. Most water treatment pitchers will remove iodine from water or you can find activated carbon sold by itself.

How Iodine Gets in Water

Iodine occurs naturally in water. It is added to water from volcanic activity, weathering of rocks and waste from medical applications. In some cases it is purposely added to water to disinfect it to make the water safe for human consumption. Radioactive iodine enters water from medical waste and nuclear accidents.

This Day in Science History - March 1 - Discovery of Radioactivity

On March 1, 1896, Antoine Henri Becqurel discovered radioactivity. Earlier in the week he planned an experiment to expose sunlight to uranium and then store the uranium in a black bag with a photographic plate. Earlier trials of the experiment resulted in an image of the uranium crystals on the photograph. He believed uranium absorbed sunlight and released the energy slowly by fluorescence. He planned to repeat his experiment on February 26, but it was cloudy with little sunlight. Becqurel decided to postpone his test and placed his uranium and photographic plate in a black bag and stored it in his desk.

When the weather cleared, he collected his materials to perform his experiment and discovered his photographic plate contained a clear image of the uranium crystals. The uranium did not need an external source to produce the image, but something inside the uranium gave off energy.

This discovery marks the beginning of the nuclear age and would earn Becqurel the 1903 Nobel Prize in Physics.

This Day in Science History - February 28 - Dord

Dord is a noun in physics and chemistry that means density. At least, that's what it meant for nearly 5 years. On February 28, 1939, the word 'Dord' was discovered to be an error in the second edition of Webster's New International Dictionary published in 1934. Dord is an example of a ghost word, or a word that was never actually used, but appeared in dictionaries.

The first edition of this dictionary had common abbreviations listed together with words alphabetically. The second edition would move the abbreviations to the back in their own special section. The the card for the abbreviation 'D or d' for density went into the wrong pile and was mistakenly combined into 'Dord'.

This Day in Science History - February 27 - Aspirin

February 27th could be considered aspirin's birthday. The process to make aspirin was patented in 1900 by Felix Hoffman on behalf of the German pharmaceutical company, Bayer. Hoffman's aspirin was a stable form of acetylsalicylic acid and named in three parts for this active ingredient. The 'A' was from acetyl, 'spir' was from the source of slaicin, the spirea plant, and 'in' was tacked on the end to give it a good pharmacological sounding name.

Drinking Bleach and Drug Tests

There are all kinds of rumors about ways you can beat a drug test. Obviously the easiest way to pass the test is to avoid taking drugs in the first place, but that's not going to be much help if you've already taken something and are facing a test. According to Snopes, some people drink bleach believing it will somehow clear their system of drugs. While it is unclear where this idea originated, the rumor is out there. Will it work? Will drinking bleach hurt you or kill you? Here's the lowdown:

Drinking Bleach to Pass a Drug Test

Household bleach consists of about 5.25% sodium hypochlorite in water. Specifically, Clorox says their bleach contains water, sodium hypochlorite, sodium chloride, sodium carbonate, sodium hydroxide and sodium polyacrylate. They also make scented products that include fragrances. Bleach also contains small amounts of impurities, which aren't a big deal when you're using the product for disinfection or cleaning, but could prove toxic if ingested. None of these ingredients binds to drugs or their metabolites or inactivates them such that you would test negative on a drug test.

Colored Metal Jewels - The Bead Test

Most people have seen colored fire, which can be used as a flame test to help identify the ions in a sample. The bead test is a related qualitative technique that involves heating sample-infused borax, microcosmic salt, or sodium carbonate beads in a flame to produce colored 'jewels' or beads representative of metal ions. You can make blue borax jewels, plus I've got instructions for producing other colors of beads... learn how

How Salt Preserves Food

Before refrigeration became common, salt was a popular food preservative. It is still used in many products, including bacon, ham, pickles, and jerky, but modern versions of these foods actually contain much less salt than the level needed to prevent microbial growth. Seawater tastes salty, yet it is only about 3.5% salt. A 10% salt concentration is needed to prevent bacterial growth and 20% salinity is required to actually kill bacteria and molds. Yet, salt does work as a preservative.