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EXCHANGE: Eclipse trackers to contribute to more research

December 22, 2018

CARBONDALE, Ill. (AP) — While most people were reveling in totality during the 2017 solar eclipse, a small team of local amateur astronomers were hard at work, carefully training their telescopes on the corona of light and plasma visible at the sun’s outer edges.

Their hundreds of photographs are now in the hands of researchers at the National Solar Observatory and other institutes, who are using them to study the atmosphere of the sun and its weather.

When combined with images from other amateur astronomer teams around the country, the Southern Illinoisans’ work will produce the best high-resolution, rapid-cadence video ever taken of the sun’s corona, which is visible only during solar eclipses, according to Bob Baer, who coordinated the Southern Illinois volunteers.

“What we can do with the images is make a movie that shows the corona evolving and twisting,” said Baer, who works in the SIU Carbondale Physics Department. “That was the big deal.”

As the local leader of Citizen CATE, the Continental-American Telescopic Eclipse Experiment, Baer spent the year before the eclipse recruiting and training local educators, astronomy enthusiasts and students to use identical telescopes and methods to image the sun.

Out of 68 teams nationwide, Baer led six, all based in Southern Illinois. And he plans to do the same during the 2024 eclipse.

But rather than twiddle their thumbs until then, Baer and other dedicated local astronomy buffs are lending their telescopes to a new nationwide volunteer project: tracking the movement of exoplanets.

Just as the star at the center of our solar system, the sun, has eight planets orbiting it — sorry, Pluto — there is probably at least one planet orbiting every star we can see in the night sky, according to NASA.

The trick is identifying them.

The best way to detect an exoplanet is to catch the very small dip in the light output when it moves in front of its corresponding star, Baer explained. Once detected, each exoplanet’s distinct orbit must be tracked and imaged.

Some exoplanets, ”“orbit their stars so tightly that a “year” lasts only a few days;” while others “can orbit two suns at once,” NASA’s website explains. Still others are “sunless rogues, wandering through the galaxy in permanent darkness.”

And with an estimated 400 billion stars in the Milky Way galaxy, and untold planets orbiting them, professional astronomers need a lot of help from amateurs like Baer and his CATE teams.

“We’ve confirmed over 3,000 exoplanets to date, and the rate of discovery is increasing very quickly,” Baer explained, as more robotic telescopes are sent into space to look around.

One recently-launched telescope known as TESS, is expected to identify over 10,000 exoplanets during its lifetime.

“TESS is already identifying earthlike planets around stars that are not too far away,” Baer said. At least not too far away in light years.

Once the researchers monitoring TESS identify a potential planet, Baer and other amateurs will step in to confirm it and image it, giving scientists more information about the star and its planet.

They’ll use the same kits they used to image the eclipse: a portable telescope, a mount, a digital camera, and a laptop. Total cost per kit is about $3700, though much of the equipment was donated, or obtained via grant funding, Baer said.

Imaging a planet’s full transit in front of its star usually takes at least 3 to 4 hours, Baer said, plus setup and takedown.

“These are all-night observations, and they’re kind of a pain to do,” he said. “We haven’t got the procedures down yet.”

Baer is still working on the protocols for the exoplanet observations, which must be established before local volunteers can get involved.

Every astronomer must use identical methods, Baer explained, to make sure their images are equal in quality, and can be translated into useable data by researchers.

“Taking data with these portable CATE telescopes is not simple,” Baer said. “You’ve got to point them by yourself. The stars are relatively dim, and you have to track yours all night.”

A successful imaging means taking a well-calibrated picture of the same star every five seconds, for hours, with no autofocus or auto exposure.

“At the end of the night you have about 2500 images,” Baer said. “Tracking the sun for just a few minutes during totality is easy, but over four hours your telescope moves a lot.”

Another big challenge will be Southern Illinois’ unpredictable weather, since an unexpected cloud can interrupt an imaging at any time, and ruin several hours worth of data.

“I had five or six attempts that were complete busts,” Baer said.

Luckily for Baer and for professional researchers, several Southern Illinois volunteer astronomers are enthusiastic about continuing the work they began with the eclipse.

“The notion of citizen scientists like myself and other volunteers is such a great way to get lay-people involved in hard science,” said Fred Isberner a retired SIU Carbondale professor in the healthcare management program. “You can really contribute without having a degree in physics.”

Since he helped image the eclipse from a CATE station in Giant City State Park, in 2017, Isberner has kept up with the work of other CATE astronomers from around the country via Facebook, and has seen his name featured on scholarly research published in several physics journals, something he never expected.

As a retired educator, Isberner said he has particularly involving other Southern Illinoisans in exploring the cosmos. His hope is to continue that momentum all the way through 2024.

“By keeping this project in the forefront and continuing to engage amateurs we’re making sure we’re going to have a good team of people for this next eclipse,” Isberner said

Several of the CATE telescopes acquired for the 2017 eclipse are now in the hands of area teachers, Baer said, including Chris Midden, who teaches 5th and 6th grade science at Unity Point elementary.

After enlisting 10 of his students to aid in imaging the 2017 eclipse, Midden will be leading his entire classes in another citizen science project, called “Protect Our Planet From Solar Storms,” in which students will analyze satellite images of eruptions in the sun’s atmosphere, helping scientists study solar storms.

And though Midden’s grade schoolers probably won’t be up all night watching exoplanets, Baer hopes he can enlist some area high school and college teachers, whose students have later bedtimes.

“It’s a pretty rigorous project,” Baer said. “But it’s a really exciting time for citizen-astronomers.”


Source: The (Carbondale) Southern Illinoisan




Information from: Southern Illinoisan, http://www.southernillinoisan.com

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