Sunday, February 28, 2010

Techfest 2010


Every year The Works, a children’s museum focusing on technology, held its annual Tech Fest. Though we have wanted to go in the past, we finally made it yesterday. Held from 9-5 at the Edina Community Center in suburban Minneapolis, the event attracted 1700 people last year and hoped to reach 2000 this year. This scientific event covers chemistry, astronomy, mechanical and electrical engineering.


We got there shortly after lunch and just in time for the second chemistry show. I have wondered what the Chemistry department does for its public outreach ever since seeing the Physics Department's show--Physics Force at Northrup Auditorium at the University Campus. Demonstrators—two women from the University of Minnesota Chemistry Department, began by dropping Mentos in a pop bottle so the carbon dioxide in the pop creates a geyser. The two women decomposed hydrogen peroxide by adding ground magnesium to it into an empty pop bottle. Water, a byproduct of the reaction is released as steam because the chemical reaction is so hot it vaporizes the liquid and partially melts the empty bottle. Physical properties are demonstrated by showing the glass threshold temperatures. Placing an onion into liquid nitrogen, normally -400 degrees Fahrenheit begins to boil and steam. The onion needs time to freeze through; when completely frozen, the young women take leather gloves and threw it on the floor. Though it crashed like a glass bottle—chemically it was still an onion. Some kids up front even complained of the onion smell. One of the women remarked, “Yes, it does smell a little. Chemistry usually doesn’t smell good.” The women explained that nitrogen can make anything freeze enough to create the glass effect—the point where any solid behaves like glass. Conversely, glass can be melted to behave like plastic. The demonstration also used balloons filled with hydrogen—like the Hindenburg, that they ignited. Adding different salts, they created different colored flames with different salts. Iron even created small sparks like fireworks.


We left the chemistry show just in time to see one of the shows of the Minnesota Planetarium. Though the planetarium awaits the construction of the new planetarium, it has a mobile show—though yesterday was shown on a two dimensional screen because of the sheer volume of participants. The show yesterday had many elements of the show at Mayo High School, it had lots of good information that was new and kept our interest. Showing us the largest canyon in the universe—Valles Marineris, the show had “brought us” to Mars. The canyon is 200 miles across, three miles deep and long enough to reach from New York to California. We also learned about light years; the light from the sun takes 12.5 minutes to reach earth and the moon. When reflected from the moon, it takes an additional 1.5 seconds to reach earth. We discussed dwarf planets; we have received only very bad pictures of Eres. In 2015 Voyageur shall pass by it and be able to send better pictures to us. Traveling at 30,000 miles per hour, it is twelve light hours away from earth. We learned so much!



After the two shows, my kids wanted to play the traffic game—Gridlock. The game can be played online by anyone who wants to. The station was run by the University of Minnesota-Institute of Technology. They also had a display explaining how the traffic control systems worked.




The kids also had a chance to examine chemical reactions by placing vinegar into a small, empty water bottle and baking soda into a balloon. The balloon was placed atop the bottle. When the soda mixed with the vinegar, carbon dioxide gas that was emitted inflated the balloon. After the balloon was tied off, the kids were able to examine the properties of the gas. Because carbon dioxide gas is heavier than the atmosphere, it falls to the ground rather than floating in the air.


There were many things we were not able to do because we ran out of time. However, there was much we could: we watched a robot by the Edina FIRST team robot, examined robotics projects made by University students, and constructed paper cars. We even brought home directions to make a drinking straw rocket. It was an extremely worthwhile visit to the cities—we had a great time and learned tons! The Works has monthly family Saturdays and several homeschool days throughout the year. We are definitely going to plan on making the trip for some of them.

Thursday, February 25, 2010

Exploring the skies at the Mayo Planetarium




One of our homeschool groups from the county decided to schedule a visit to the Rochester Public Schools' planetarium at Mayo High School this morning. We had such a great time. It was an incredible show! Narrated by the staff member, it began with an engaging explanation of the most common constellations. It was interesting to have him explain to the kids why the sky and its contents move. A common and repeated theme was chimed by the audience when prompted: "Planets look like stars but act like the moon." The staff member explained why the sky changes.



Stars, while not maintaining their exact location, appear to stay stagnant day after day. Only when comparisons are made of the night sky after a bit of time has passed, will the change be noticeable. The planets were then examined and they learned that major differences can be seen in just one twenty four hour period. We pretended to have a planetarium pajama party and noticed that the night sky moves as well--if we go inside to play some games, when we come back out, we will see that the sky has shifted over us.



The earth, moving at 1,000 miles per hour cannot be felt because the movement is smooth. We cannot see the moon move above us, despite its 2,000 mile per hour rotation, because of its distance from the earth. We watched a very cool artist rendition of moving to the edge of the solar system...and we thought poor de-planetized Pluto was it. We saw the irregular orbits of the dwarf planets and asteroids. On the very edge, we discovered ice bergs swallowed us. Our own sun began looking like a distant star twinkling in the night sky. I am totally ashamed to admit that I was unaware additional dwarf planets Ceres and Eris--guess this and my memories of when Pluto was a planet dates me. We "zoomed" back towards earth and discussed the planets, Saturn and its spectacular rings, twins Neptune and Uranus made out of frozen gases, Mars with its enormous volcanoes--the largest which would be as big as Minnesota!

The Rochester planetarium has public shows that are available through the Rochester Community Education site. There are some wonderful sites both Cornell University and Nasa have some interesting information. This made me miss the planetarium in Minneapolis that was a top the old Minneapolis Public Library. It is supposed to be rebuilt on top of the new library; -it is tentatively planned to open again for 2013.

Monday, February 1, 2010

Catapults and trebuchets….tweener style



My boys are well….boys. They are very different from my daughter, who had even outgrown any vestiges of her former girly girl self by the time she was four. Given their subjects of interest are often quite different than those my daughter, it shouldn’t have surprised me when they discovered a catapult model building class while perusing a flyer for youth community education classes in Rochester. Truth be told, they almost convulsed with excitement.

This caused me a bit of concern. At the county fair last August, my older son had seen a model that could have thrown small boulders. Despite the engineering curiosity and the intense desire to learn, this was not an object I wanted my children to posses. My boys are very kind hearted and I love them dearly; however, they do not always think prior to acting and I could only picture a broken window in the future. I was scared—windows are expensive.

My kids are also pretty good about not constantly pestering for lots of “stuff.” They are aware educational items are surely to win out over a new game and they know they better pick and choose wisely. After the class had been brought up numerous times, I finally relented despite very grave concerns. We drove down and registered for the class. I was immediately second guessing my sanity.

My daughter and I delivered them to their teacher the night of the night of the class. We spent the better part of two hours wondering what we had just done. When we returned to retrieve them, they stood in front of miniature catapults. We smiled; powered by a rubber band, it was big enough to toss a marble. They excitedly chattered about military history and pointed to the whiteboard asking me if I knew what that was drawn up there. I felt a little proud and a little mischievous as I was about to crush them with my answer: “Why that is a trebuchet.” Yes, a girl—worst of all, a mom, knew what that was. Secretly, I think they were a little proud—the dad next to us had no idea.