Grosse Pointe North's radio astronomers
keep an electronic ear cocked to space

Most high school students aren’t allowed to handle power tools on school property. Most aren’t permitted to walk on the roof. Most don’t have access to high-tech electronics and sensing equipment.

The students in Grosse Pointe North High School’s astronomy club aren’t most students.

The RATz, short for Radio Astronomy Team, built the radio telescope that stands atop North’s Science Building. Guided by Ardis Herrold, an astronomy and earth science teacher at North, the RATz maintain the telescope and use it to observe objects in space. It’s a unique, hands-on experience not available at most high schools.

Radio telescopes are used to study the radio waves emitted by celestial objects such as supernovas, hydrogen clouds, the moon and sun, and the Milky Way. Unlike an optical telescope, which collects visible light, North’s radio telescope collects invisible radio waves and doesn’t require a dark, clear sky to be effective.

“We started this with the idea that radio telescopes don’t care that it’s daytime, because they’re not looking at light. They don’t care if it’s cloudy, like it usually is in Michigan. They don’t care about light pollution, and we can use it during the school day any time we want. So this is a nice advantage to us,” Herrold said.

North’s radio telescope is shaped like a satellite dish. Its curved dish, 18 feet across, is made of metal mesh and acts “basically like a big mirror,” Herrold said.

Radio waves from space bounce off the mesh and hit an antenna. The signal is processed by electronics on the telescope and sent via a cable to the club’s control room where it can be analyzed.

A radio telescope doesn’t produce a “picture” like an optical telescope. Data collected from the radio telescope is graphed according to the intensity of the radio waves.

The RATz can use those graphs to determine whether an object is moving toward or away from the telescope by measuring its Doppler shift, the change in frequency of a radio wave emanating from a moving source. They can also use false color imaging technology to create a multi-colored map of the signal. The principles of false color imaging – making a picture of something invisible – are also used in medical imaging.

Most of these calculations are handled by computers, but when the RATz started meeting in 1989, all the work was done by hand.

But that wasn’t the only complication the original RATz faced; when building their first radio telescope, the RATz faced skepticism and doubt from their peers, and even from teachers, Herrold said.

“I think the original kids were gutsy, because everyone laughed at them. Everyone said, ‘You can’t do this. It’s never going to work.’ They had to take a lot of grief. But then they got a lot of reward when everything worked,” she said.

Today’s RATz are continually fixing and updating the telescope, which has been rebuilt a few times since its first iteration.

“Ours is kind of a living project,” Herrold said. “We’re doing something new and different every year as we evolve this telescope.”

During one recent after-school meeting the students were estimating the total weight of the telescope, information needed to make adjustments to the motors that move the dish. High school students from all grade levels worked together to count and weigh components of the dish. Some members are science buffs, and some just joined the club to be social, Herrold said.

Andrew Remenar, 17, belongs to the former group.

“I’m one of like two people I know who joined because of the actual science, instead of the power tools on the roof bit,” he said.

Experiencing hands-on, trial-and-error work like their project that day helps students learn how to think “like a scientist and an engineer,” Herrold said.

“We wave our hands and we draw pictures and we think about things and we try it, and then if it doesn’t work we try to figure out why it didn’t work and that are we going to do next. And that’s how it works,” she said.

North’s radio telescope isn’t intended to help students “make the next great scientific discovery and show up the scientists,” Herrold said. Rather, her goal is to help students develop valuable critical thinking and analytical skills.

“To get somebody through high school understanding what we’re doing, how we did it, is a huge triumph. And to get it to work occasionally is a bigger triumph,” Herrold said.

“And it’s just weird. And high school, weird – they go together,” she said.

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