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Stationed beneath a white tent on a campus lawn as the still-summer sun baked the experimenters and their equipment, UNLV engineering student Rabih Chaar hit send on an email.

The ground station delivered the coded communication through a satellite network up into the air, telling the helium-filled balloon — looming large and floating almost as high as the surrounding trees — to vent.

Several minutes ticked by before the student-faculty team realized that something was awry. The balloon, carrying experiments in a trail of neatly packaged payloads, was not coming down. The issue: a dead battery.

“And that’s why we do the test run,” said Lloyd Ramirez, a mechanical engineering major.

“Venting is the hardest part of all of this. I prefer to have things like this happen, because then we know what else to add to our checklist for day-of nuances that don’t normally happen.”

That day will be Oct. 14, when an annular solar eclipse will be visible in Las Vegas and will cross directly over eastern and northern Nevada. Ramirez and his teammates will be stationed in Winnemucca at prime time to participate in NASA’s (NEBP).

Their goal is to launch a balloon — carrying a 12-pound payload and livestreaming cameras — about 100,000 feet into the Earth’s stratosphere to collect data during one of the rarest celestial events. 

“It doesn’t happen all that often, so we have to take advantage of it,” said Matt Pusko, assistant professor-in-residence for the UNLV College of Engineering and project lead. “There won’t be another annular solar eclipse anywhere close to us for at least 15 years.”

UNLV's Ties to NASA

One of several teams across the nation, UNLV was selected by NASA to participate in NEBP’s engineering category for not just one, but two eclipses. This month’s annular solar eclipse serves as a precursor to the total solar eclipse on April 8, 2024. 

“The No. 1 purpose of the project is to educate people about the fact that the moon actually goes around the Earth, and this whole system goes around the sun,” said Pusko. “It’s a great outreach opportunity. And at the same time, it’s a chance to do some cool engineering stuff.”

All teams will participate in both events, and the resulting data will be analyzed and made publicly available. A couple of other university teams will be stationed alongside UNLV in Winnemucca.

UNLV’s team roster includes seven undergraduates, one graduate, and student and faculty collaborators from the University of Nevada, Reno.

“The more balloons we can get up in the air, looking back down at the shadow moving across the Earth, the better we can really see what’s happening,” said Pusko. “You can actually watch the balloons on a map and see what’s their current altitude, what’s their current speed, what’s the temperature up there.”

‘Smack dab in the middle’

On a Sunday morning in mid-September, students gathered on UNLV’s campus to do a complete dry run of the launch, from set up to tear down, and to practice their various roles. The team laid a blue tarp on the lawn adjacent to the chemistry building, set up their ground station and radar dishes, and ensured that their experiments were safely packaged and tied together in a paracord harness system. 

“We’ve got these paracord lines to connect the boxes and they’ll be ascending one after the next about 7 feet apart,” said Lea Wigington, a civil engineering major. “They have to descend in a particular order, because the closer they are, the easier they communicate with each other.”

As the simulated launch proved, something as seemingly simple as a battery problem could set them off course. And when the eclipse is passing through, the team only has a finite amount of time to make sure the balloon launches without a hitch.

 begins at 8:06 a.m., with annularity starting at 9:20 a.m. and lasting for only a few minutes. The partial eclipse ends at 10:47 a.m.

“Someone is going to be in charge of the camera payload and they make sure the battery is plugged in, turned on and we’re getting a feed,” Pusko said. “We also have the satellite modem which allows us to talk through the internet up to the balloon. That lets us do things like open the vent to allow it to go neutrally buoyant, and we can also send a line to cut the balloon down.”

Achieving neutral buoyancy — which means that once the balloon reaches a predetermined altitude, it floats there without climbing any higher — is a chief project goal. They want to make sure the balloon doesn’t pop unexpectedly and bring their experiments crashing down. The team also wants to measure atmospheric gravitational waves.

“When the moon goes in front of the sun, we’re going to have a little more gravitational pull from the sun and the moon because they’re both in the same direction,” Pusko said.

Next Up: The Total Eclipse

For the total solar eclipse on April 8, 2024, UNLV students will have to travel a little farther to launch their balloon and accompanying payload, as the eclipse takes a different path across the nation.

“We’re going to Texas to get inside the totality of it,” said Ramirez. “We’ll be smack dab in the middle of it.”

The balloon’s payload will also likely include additional and potentially more challenging experiments that the team will develop over the next several months, possibly in partnership with researchers across campus.

“I think today’s simulation makes it really rewarding,” Ramirez said as the balloon began to vent and descend. “Being able to see the balloon up in the air after months of work has been really exciting. I’m looking forward to our October launch, but I can’t wait for April. It’s going to be a longer and bigger eclipse."