Educator How-To: Crystals, Geometry and Chemistry

Math is beautiful and inescapable. Especially in nature, patterns and equations just keep showing up.  The path of an orbiting planet, the growth of a nautilus, arrangements of leaves on a stem, the efficient packing of a honeycomb; we can find rules and algorithms and make predictions from them.

Crystals, with their obediently repeating structure, are an elegant manifestation of the ‘rules.’  To be a crystal, your building blocks (atoms, molecules, or ions) must follow patterns over and over and over and over and over.  Atoms, being predictable, simply do what their chemical properties and the conditions (temperature, pressure, etc.) indicate.  So what exactly does it take to go from a mess of elements and compounds to this[picture of green “Crystals of India” crystal specimen] example from the Crystals of India exhibit at HMNS Sugar Land?

If you’ve ever tried making rock candy from sugar water or ornaments from borax solution, then you have some idea what it entails: something dissolved that is capable of making crystals has to slowly come out of solution – usually the longer you give it, the bigger it can grow and the slower it grows, the more perfect the crystals.

Freezing water into ice also gives you crystals; they just don’t stick around and let you handle them conveniently at room temperature. Water and solutions in water aren’t the only way to get crystals; molten rock cooling (slowly) can also give crystals, but that’s a little tricky for home experimentation.

So time is your friend for crystal growth, pressure is a factor, and it needs to be easier for atoms to attach to the forming crystal than to stay in solution.  Having a solution that is saturated or supersaturated so it can barely hold all of the dissolved material helps. It also helps to have places for the crystals to start forming; a tiny ‘seed’ crystal or sometimes even just a rough spot on a surface can provide the nucleation sites to kick off crystal growth. Are there other ways crystals and the things we consider ‘gems’ can form? Yes!

For those of us with shorter attention spans, a cool way so see the process is with crystallizing hand warmers – a pouch holds a saturated solution of sodium acetate. When you flex a metal disk inside the pouch, you kick off a chain of crystallization and end up with solid material (and released heat energy).  Because the process is so fast in the hand warmer, the individual crystals are very small and jumbled up (polycrystalline); oriented in all different directions, and as a mass they are opaque (light is refracting all over the place) and relatively dull rather than shiny and smooth as slower-forming large crystal faces can be.  The structure of most metals is also polycrystalline, and things like plastic and glass (even the kinds misleadingly labeled “crystal!”) are amorphous.

The external crystal shapes we see are related to the internal structure – there are a lot of different ways atoms can pack together.

Practically, there will always be some disruption in a crystal structure, no matter how perfect it may appear, which allows for some very cool effects – crystals “twinning,” impurities that alter the color; the reason ruby and sapphire (both corundum crystals) appear different.

Crystals aren’t always pretty! Sometimes we want to prevent crystallization to avoid things like kidney stones, but crystals are useful for all kinds of things; optical equipment and lasers, X-ray crystallography to figure out structures of proteins (and once upon a time, DNA), and silicon chips used in electronic devices. 

Whether you prefer your crystals practical or decorative (photo of white spikey crystal from Crystals of India), they are amazing!

Can’t get enough crystals? Check out the Crystals of India exhibit at HMNS Sugar Land (free for members!)

 

 

Unmasking Everyday Superheroes with HMNS Outreach!

Editor’s Note: This post was written by HMNS Outreach Presenter Sahil Patel.

Up in the sky, look! It’s a bird! It’s a plane! Wait, no, it actually is a bird, flying faster than most cars.

Superpowers, such as the Flash-like super speed of the peregrine falcon above, are abundant throughout the natural world and specifically highlighted by several specimens in the HMNS Outreach collection.

Superhero Hamilton

Meet Hamilton the blue-tongued skink, who has the ability to regrow most of his tail should it be separated from his body!

In addition to a stuffed peregrine falcon that travels with our Texas Wildlife program, the TOTAL Wildlife On Wheels lineup is full of noteworthy unlikely heroes. Like Wolverine of X-Men, traveling specimens such as our blue-tongued skink from Reptiles & Amphibians or starfish from Invertebrates exhibit regeneration after loss of tail and limb, respectively.

Ed Bugs 3

Vinny the vinegaroon has an awesome superpower, the ability to spray acid with his abdomen!

Our newest LyondellBasell Bugs On Wheels program, Awesome Arachnids, gets your Spidey-Sense tingling with a few undercover superheroes. The program will bring out specimens such as an emperor scorpion, which glows electric blue under ultraviolet light, and a vinegaroon, which sprays an acetic acid and caprylic acid mixture from its abdomen when threatened. And don’t forget about the wall-crawling creatures that spawned Spiderman! Awesome Arachnids also features two tarantulas, who can climb with special retractable claws! 

Superheroes like Batman and Iron Man use science and technology to their advantage when fighting crime, and after a ConocoPhillips Science On Stage presentation, your knowledge of chemistry or physics can rival theirs! Learn about the super heat used to produce colors in fireworks with Cool Chemistry, or explore the tricks anyone can use to acquire super strength through simple machines with Motion Commotion!

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Stepping back in time 70 million years could have brought you face to face with these supersized T. rex teeth!

Very few superheroes have the ability to travel through time, but kids can harness this ability through Chevron Earth Science On Wheels! Shift back millions of years and explore the characteristics and adaptations of prehistoric life with Dinosaur Discovery, or combine time travel with super smarts in Know Your Rocks, in which students save the day by classifying different types of rocks.

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Children and adults alike love the Discovery Dome for its superb selection of shows, available in English and Spanish!

We certainly can’t forget about the superhero qualities of the men and women working in outer space. With hazards ranging from freezing temperatures to rapidly moving matter to a lack of air, outer space is a place fraught with danger. Learn more about the extremes of life in space and much more with our Discovery Dome, which features a wide selection of shows from the Burke Baker Planetarium!

Every hero has a story, and you can unmask your own with HMNS Outreach, courtesy of your friendly neighborhood science museum.

Contact us at outreach@hmns.org or (713) 639-4758 to book your HMNS Outreach program today!

The Secret Handshake: Presenting Business Cards in Japan

Editor’s Note: This post was provided by Kuraray, local sponsor to the special exhibition Samurai: The Way of the Warrior on display now at HMNS.

“Do you have a card?” is a phrase uttered daily in American business. To us, it’s a piece of paper. We take notes on them, stuff them in our pockets and hopefully file them for future easy access.

But, in Japan, business cards are considered extensions of the individual — formal self-introductions that are treated with the utmost respect.

As such, “meishi koukan” (the exchanging of business cards) commands a distinct level of etiquette, complete with its own process:

  • Remove cards from an actual business card case prior to the meeting and place them on top.
  • Beginning with visitors, highest-ranking attendees exchange cards first. This helps the Japanese learn who is in command.
  • Hold card on the top corner with right hand and offer it with the information facing out. Left hand holds the case.
  • Briefly introduce yourself as you present the card, stating your name and company.
  • When other person reciprocates, receive card with your left hand. Carefully read the information. Restate the person’s name and thank them.
  • Display cards received during the meeting, arranging them from left to right in the order of seating (from your point of view). Learn the names of the people you are speaking with and show respect.

Other tips to remember:

  • Never stuff a card into your pocket – it’s considered extremely rude.
  • It is a direct insult to bend, damage or write on the card in front of the owner.
  • Always maintain an ample supply of cards. You may distribute dozens in a larger meeting, and give multiples to the same person.

Despite these rules, every situation will be slightly different and your Japanese counterparts may have another understanding of what is considered protocol. When in doubt, always err on the side of showing respect and politeness.

 Want to learn more about Japanese culture and traditions? Visit HMNS to see Samurai: The Way of the Warrior, on display through September 7, 2015. Local support for this exhibit is provided by Kuraray.

 

Mark Your Calendars for these events happening at HMNS 1/19-1/25

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Bust out your planners, calendars, and PDAs (if you are throwback like that), it’s time to mark your calendars for the HMNS events of this week! 

Free Shipping, No Minimum Sale at the Museum Store
Sale valid from 1/15-1/25
For a limited time receive free shipping on any online order at the HMNS Museum Store. Use promo code FREESHIP. Shop now!

The Educator Event @HMNS
Saturday, January 24, 2015
8 a.m. – 1 p.m.
The Houston Museum of Natural Science is proud to present The Educator Event @HMNS on January 24, 2015. This conference-style event gives educators a unique chance to learn about the educational opportunities provided by museums, educational nonprofits and local organizations in and around Houston. Attendees will earn three hours of CPE credit by attending a variety of exciting, hands-on workshops and participating in an exclusive, self-guided tour of our Wiess Energy Hall!

Family Space Day
George Observatory 
Saturday, January 24
Blast into outer space on a simulated space flight to the Moon! The Expedition Learning Center at the George Observatory will be open for individual children and adults to sign up for missions. No danger is involved! Astronauts are assigned jobs aboard the Space Station Observer and work together as they solve problems and have fun. Volunteers who work at NASA will run the missions and visit with the participants. Don’t miss this special opportunity to participate in real astronaut training! Limited expedition times available, reserve your mission now!