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Purdue Physics seniors take to the sky to recreate 100 year old experiment


Purdue Physics senior Chris Kraner

Purdue Physics senior Chris Kraner and the program's cosmic ray detector will travel in a hot air balloon in the early spring to recreate physicist Victor Hess' experiment from 100 years ago.


For new science to be discovered, bright men and women have had to think against the grain for centuries

Their bold ideas were often met with derision, even from fellow scientists.

A century ago, radiation was commonly thought to originate from the ground we walked on, the earth. Using primitive electroscopes to obtain their measurements, early 20th century scientists saw that the further you are from the ground, the weaker the readings became. They used the top of the Eifel Tower for this conclusion, which stands more than 1,000 feet in the air.

Austrian physicist Victor Hess sought to test further. He set up a hydrogen balloon flight, packed up his instruments and soared to an astounding 17,400 feet in the air — a dangerous prospect for any balloonist today but especially back in 1912.

The daring flights Hess endured saw radiation levels go down at about 2,000 to 3,000 feet but then dramatically increase the higher he went. Hess had discovered what would later be dubbed cosmic rays. He was awarded the 1936 Nobel Prize for his findings.

What Hess found would help open the door to many other discoveries in nuclear physics. The electron had been discovered just 15 years before Hess climbed into the balloon. Cosmic rays were eventually found to be mostly protons with small percentages of alpha particles, charged particles, electrons and antimatter particles.

The Purdue Physics Outreach will recreate the balloon flight with Physics senior Chris Kraner and Stephen Claypool, a senior at McCutcheon High School, as the main passengers and scientists. McCutcheon is one of the many area schools Physics Outreach works with. McCutcheon physics teacher, Cheryl McLean was also one of nine teachers participating in a weeklong 2012 summer institute dealing with cosmic rays, their detection and analysis.

The students will be taking up a cosmic ray detector, a much more modern piece of equipment that what Hess got to use. The device is comprised of scintillation plates and photo multiplier tubes that send readings for a computer to translate. The device measures “counts,” which increase when levels of cosmic radiation are more intense. New with the 2012 software updates, the cosmic ray detector can now give real-time results and draw graphs as soon as the counts come in.

Reaching new heights

Claypool and Kraner have already tested their detector on the ground and in a four-seater airplane that soared to 9,000 feet. Claypool is looking forward to seeing how the machine works in the open air, floating at 10,000 feet.

“I’m a little bit nervous because I’ve never been in a hot air balloon before but I think it’s a really good opportunity,” Claypool said. “It’s really important to think of how a scientist that first discovered these things would have gone about it in modern days.”

The launch is set for “early spring” 2013, according to David Sederberg, director of Purdue Physics Outreach. It will either take place around Greater Lafayette or Indianapolis. Two central Indiana balloon companies, Midwest Balloon Rides and Stars and Heights, are aiding this project. They gave Sederberg the window of January through May but he anticipates it will most likely be by late January when Kraner and Claypool take to the skies.

Claypool and Kraner will be the only ones in the balloon but a basecamp of scientists will be on the ground, monitoring their measurements.

Science superstar

McCutcheon physics teacher Cheryl McLean selected Claypool for this event for his outstanding science work in and outside of class.  

“He’s always engaged in modern science,” McLean said. “He has a love for it, an interest in it and he puts time in it. … He does his calculus two weeks in advance.

“When you have a student that is highly motivated to work independently like that, this is a natural thing for him to spend time on. That’s what you need: someone that will go above and beyond. And he’s really good with technology.”

Claypool’s science abilities are broad. He excels in most STEM-based classes. However, working with the cosmic ray detector combines his loves for computers and astronomy.

Claypool has been working with Purdue Physics since the summer and he plans on attending Purdue in the fall. However, the teen hopes to study Computer Information Technology with a specialty in Information Systems.

Tremendous opportunity

McLean is thrilled for Claypool’s opportunity to be a part of a project that goes far beyond a fundamental high school physics class.

“It’s really hard to teach a subject like chemistry or physics when you spend a year or two or three years on fundamentals,” McLean explained. “The current research is really exciting and it’s not in text books.”

“When we have an opportunity like this, not only does it help me to get connected to my colleagues to be connected to current research, it helps me bring the opportunities back to the classroom.”

Kraner, a native of Mishawaka, wishes he had such an opportunity when he was in high school.

“I could never dream of doing something like this in high school,” Kraner said. “We went up in the airplane a couple months ago and Stephen pretty much ran the experiment. I was just kind of there for some moral support. He did very well. It’s an absolutely fantastic opportunity for him.”

Kraner was chosen from his work in the Cosmic Ray Detector Program at Purdue Physics, as overseen by Prof. Matthew Jones. Hess’ landmark experiment was one of the reasons Kraner joined the program. 

 “I think it’s awesome,” said Kraner, who has done independent research on Hess’ experiment and the history of cosmic rays. “I’m really excited to do it. I’m a little hesitant on it, too, because I’ll be basically standing on a platform up high in the air. I’m a little worried about that but I think it’s going to be a whole lot of fun. I think it’s also really cool that we are doing this in the form of Victor Hess’ experiment. Really recreating that historical thing is something that is fantastic.”


McCutcheon High School senior Stephen Claypool

Stephen Claypool spends some time with the cosmic ray detector at the physics and chemistry room at McCutcheon High School.

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