Tensile Intergrity Sphere

Hanging high above the center of the MOSI Grand Lobby is a very large and odd-looking sphere composed of yellow rods and wire. If you spend a few moments and really look at the sphere you will see that none of the yellow rods that compose the sphere are touching each other. This neat bit of science is known as a Tensile Integrity Sphere.

How does it work?:

A tensile integrity sphere or tensegrity sphere is a structure that utilizes synergy of components in balanced compression and tension for structural support.

Compression is stress or force applied to materials resulting in their compaction. In the case of this sphere the yellow rods are under compression. Tension is a force that pulls upon an object using strings or wires and is the opposite of compression. The wires in the tensegrity sphere are in tension. Synergy is a situation where different entities or forces cooperate advantageously for a final outcome, in our case keeping the sphere round without external supports. Utilizing the forces of compression and tension in synergy this 130 pound sphere is entirely self-supporting and hangs from the ceiling with just a few strong cables that support the weight of the entire sphere.

Tensegrity:

The concept of tensegrity was popularized by R. Buckminster Fuller and Kenneth Snelson at Black Mountain College in the 1940's. Building upon an early design of a self supporting sphere structure used as a planetarium in Germany, Fuller and Snelson explored concepts of tensegrity.

The term 'geodesic' was coined by Fuller and applied to structures that could be incredibly light for their size when compression and tension were used in balance to create structures that were self supporting. Within a geodesic dome, no internal supports are required. Just imagine your house without any need for walls! Geodesic structures had potential to be spacious, light weight, strong and inexpensive to produce.

"Ability to respond as a system means that local stresses are being uniformly transmitted throughout the structure, and uniformly absorbed by every part of it. The system's symmetry is not deformed: the system expands as a whole or contracts as a whole. This is not the behavior we are used to in any structures of our previous experiences. The compression members do not behave like conventional engineering beams... Ordinary beams deflect locally. The tensegrity "beam" does not act independently of "the whole building" which contracts only symmetrically when the beam is loaded. The tensegrity system is synergetic - a behavior of the whole unpredicted by the behavior of the parts" -R. Buckminster Fuller. Synergetics: explorations in the geometry of thinking. New York, Macmillan, 1975

The story of our sphere:

In November of 2000 the museum was approached by Richard 'Dick' Avery who had an interesting proposal. He wanted to build an enormous tensegrity sphere for the museum to display. Dick had found a book on R. Buckminster Fuller in the Science Store at MOSI some time before and had become enamored of the concepts of tenesgrity. At home in Sun City Center, Dick had already built a few tenesgrity spheres and offered to build one for MOSI.

Dick spent 107 hours constructing the sphere in January and February of 2001 and shortly after it was hung in our grand lobby. It was quite a sight to see a gigantic yellow sphere sitting on the floor of the lobby and several exhibit technicians carefully considering how they were going to hoist the monster shape into place. After a few hours, the great tensegrity sphere hung above our lobby and hangs there to this day. Mr. Avery passed away several years ago, but his creation still looms larger than life over hundreds of thousands of people each year.

Diplodocus in the Grand Lobby

Around 150 to 147 million years ago, at the end of the Jurassic Period, enormous sauropod dinosaurs roamed wide portions of the planet.

Around 90 feet in length from head to tip of the tail, the Diplodocus would have needed massive amounts of food to sustain its huge size. Diplodocus likely grazed its way through the western North American conifer forests using its peg like teeth to strip foliage from trees and low growing cycads and club mosses. Their long necks may have allowed them to reach into thick-treed forests where their bodies were too big to enter, reach foliage higher up in trees or even be able to graze on soft water plants while still standing on dry land that would support their 10-16 tons of weight. The heads of these massive dinosaurs measure less than two feet in length, leaving only a tiny amount of space for a brain.

First discovered in 1877 by Earl Douglass and Samuel W. Williston, diplodocus fossils have been found throughout Colorado, Wyoming, Utah and Montana. Diplodocus, meaning "Double-beamed", was named by paleontologist Othniel C. Marsh in 1878 for the chevron shaped bones on the underside of its tail.

The MOSI Grand Lobby houses two full sized Diplodocus skeletons which are actually casts of the same fossilized Diplodocus. One is shown in a standing position and the other placed in a rearing position with its head reaching high up toward the ceiling. During the Assemble a Sauropod project over 500 donors came together and along with two grants MOSI was able to purchase two Diplodocus casts!

Because the are so fantastically large, there are literally dozens of angles from which to view the Diplodocus. Great spots to see these skeletons are the Grand Lobby, 2nd floor balcony near Weather Quest, Grand Staircase, 2nd floor Lobby overlook and the 3rd floor balcony by Science Works Theater.

The Diplodocus have been known to wear the occasional Santa hat around the winter holidays. On their tiny heads an average person-sized Santa hat works quite nicely!

Getting Ready to go Back to School can be a whole bunch of fun!

Ready for School? Come to the Back to School Expo at MOSI and have the chance to win tickets to see the Jonas Brothers Concert

The Back to School Fair at MOSI on August 15th will have everything you need to prepare, protect and inspire your child before they go back to school. Health & Wellness, Safety, Private Schools, Childcare and Learning Centers, Local Resources, Afterschool Programs, Tutors, Children Retailers and more!!

Bring the whole family and for $10 per person they will enjoy all of MOSI’s exhibits including the new ANIMATION featuring Cartoon Network along with enjoying free activities, arts & crafts, games, workshops, live entertainment and informative speaker sessions- all day. Thousands of dollars worth of prizes given away every hour including tickets to the Jonas Brothers Concert. Come meet Scooby Doo, Dexter and Toots live in person. (MOSI members are free to the back to school event . ANIMATION featuring Cartoon Network exhbit fees apply )

The first 100 kids at the event will get a free back to school goodie bag filled with supplies and goodies from Tootsville.com and MEAD

Are you a Toon Idol?

Dress up as your favorite cartoon character and perform their theme song in MOSI’s Toon Idol Competition. Performers must submit your video through August 15, 2009. Once submitted, people will have a chance to vote for their favorite video on MOSI’s YouTube™ channel.

Visit the MOSI website to download contestant application and rules. Characters of all ages welcome.

Funky Science: Lava lamps

The Science Store at MOSI has a really huge lava lamp on display and lots of smaller lava lamps for sale right now. The large lava lamp is really awesome to watch so I thought perhaps we should talk about the science of lava lamps!

Lava Lamps: Lava lamps, also known as liquid motion lamps, have been around since the 60's. They are very cool to watch but there are some neat principles of science in action.

So how does a liquid motion lamp work? Liquid motion lamps require the use of two insoluble, near equal density liquids and a heat source used for adjusting the density of the liquids. Now lets break that down into bite sized pieces.

Liquids: One liquid forms the slow moving blobs, like in the picture, we will call this Red. The other liquid allows the blobs to float about, we'll call this liquid Purple.

• These liquids must be immiscible, or mutually insoluble. This means that neither liquid will dissolve the other like oil and water and that Red and Purple will remain separate.


• These liquids must be of a nearly equal density.

When turned off, liquid motion lamps appear to have two distinct layers of liquids . One is just slightly more dense than the other and lays on the bottom of the lamp. In our case the Red liquid is slightly more dense than the Purple liquid. Being more dense causes the Red liquid to sink to the bottom.

Heat: The heat source in a liquid motion lamp is generally a light bulb or lamp. As you likely know, light bulbs can get pretty hot when they have been turned on. When the lamp is turned on it heats up the slightly more dense Red liquid at the bottom of the lamp.

Changing the temperature of a compound is an easy way to change density. When a compound is heated the molocules in the compound spread apart making it less dense. As the density decreases, the compond become lighter and will rise above heavier, more dense compounds. For example, think of air: hot air rises and cold air sinks. Heated air becomes less dense and becomes "lighter" which causes it to rise above the more dense, "heavier" cool air.

Much like hot air, the Red liquid at the bottom of the lamp will become less dense as it is heated. This makes the Red liquid "lighter" and it begins to rise in blobs through the Purple liquid.

As they rise through the Purple liquid and away from the heat source, the Red blobs lose heat. This causes the molecules in the Red liquid to move closer together and this increases the density of the Red liquid. The Red blobs are become more dense than the Purple liquid and sink back to the bottom. At the bottom the Red liquid is warmed up again and the process repeats until you turn off the lamp and all the Red liquid cools down.

This really neat Wiki How article shows you how to make a liquid motion lamp with household items and no heat! Be a scientist at home!

Volunteering at MOSI

Smiling volunteer faces on a Monday morning!

MOSI is always looking for a few good volunteers: As the “face of MOSI” volunteers help guide, teach and enlighten museum guests. We are looking for energetic, interested and exciting individuals to help bring MOSI’s exhibits to life. If you are an outgoing individual with a desire to work with people and enjoy a wide range of opportunities, then MOSI is looking for you. Morning and afternoon shifts are available Monday through Sunday. All of MOSI’s volunteers must be 14 years of age or older. Additionally, volunteers must be willing to commit to a minimum number of shifts per week and a minimum number of consecutive weeks of volunteer service.

Follow this link for more information on volunteering at MOSI and for the MOSI volunteer application!

This Rocks! Herkimer Diamonds

Tucked away in a lesser known gallery of MOSI you can find these gems glittering away.

Crystal Diamonds:

Known as Herkimer diamonds, these beauties are double terminated quartz crystals that each have 18 facets. The crystals are known for their clarity and became referred to as "diamonds". The most perfect crystals are usually less that 1/2 inch in length and the crystals are often found in clusters sometimes attached to each other. A Herkimer diamond scores a 7 on the hardness scale whereas a true diamond is a perfect 10. Large pockets of these crystals were discovered in the exposed outcroppings of dolostone in the late 1700's in several areas of up-state New York particularly Little Falls in Herkimer County and also along the Mohawk River Valley.

Making Herkimer Diamonds:

Approximately half a billion years ago the shallow Cambrian Sea lapped against the base of the ancestral Adirondack Mountains in the area now known as Herkimer County, New York. Limey sediments slowly accumulated and became compacted by more and more sediment under the salty waters where they formed into a rock strata of dolostone. Dolostone is a sedimentary carbonate rock rich in mineral domomite and is often known as dolomite rock. Still beneath the ocean, water seeped through this rock and dissolved away pockets known as "vugs". Inside these vugs the tiny crystals began to form, often thousands in one place.

Unusual Crystals:

Although many Herkimer diamonds are perfectly clear and glitter just like their namesake, some of the crystals form with impurities inside. Some contain anthraxolite which is decayed plant matter that appears black and coal-like in color. Some crystals contains tiny pockets of water inside and are known as enhydro crystals.

Other crystals may contain various impurities that give them a smoky color. Some, known as phantom crystals, have one crystal that has grown around another so that both crystals can be seen, one inside the other. Other usual crystals have grown together so that two or more crystals are fused together.

Several of our crystals on display contain anthraxolite and one has a distinctly smoky color.

See them at MOSI:

To see our collection of Herkimer Diamonds head into the Science Library just off of the MOSI Grand Lobby. The Science Alcove collections are located at the back of the library on the right hand side. Minerals, fossils, shells, vintage calculators, bird eggs, shark teeth and mounted butterflies are just some of the collections on display. The Herkimer diamonds are displayed on a black cloth on the bottom shelf of the display cabinets. Look for the sparkle!