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For two minutes and 40 seconds on Monday morning, a swath of the United States will experience total darkness as the moon intrudes between the sun and earth.

The temperature will drop. Street lights will come on in some cities. Birds and other animals, confused by the sudden coming of night during the day, will act strangely.

The eclipse will begin shortly after 9 a.m. Totality will occur in the Willamette Valley from 10:19 a.m. to 10:21 a.m.

Organizations and businesses across Oregon are expecting to cash in on the eclipse, from holding special events to filling every available hotel room and campsite. But for scientists and engineers, the eclipse is a rare opportunity for study.

Several Oregon universities and high schools are among 55 teams participating in an effort supported by NASA to livestream the eclipse and learn from it.

Teams from Portland State University, University of Alaska-Fairbanks and Oregon Institute of Technology‘s Wilsonville campus will launch high-tech weather balloons from the Crop Science Building at Oregon State University‘s Corvallis campus. A Montana State University physics professor, Angela Des Jardins, is leading the project.

The balloons are equipped with cameras and other instrumentation to document the eclipse. A team from Linn-Benton Community College will launch a balloon from a boat floating off of Newport.

The OIT balloon’s payload also includes micro-bacteria that will be studied for its reaction to Earth’s stratosphere, which is thought to be similar to that of Mars.

OIT’s balloon will rise to about 80,000 feet to record the moment of totality. It will continue to ascend before bursting at approximately 101,000 feet.

鈥淔rom there, it looks like it’s in space,鈥� said Leif Eccles, assistant professor of applied physics at OIT-Wilsonville, who is leading the OIT team. 鈥淵ou can see the curvature of the earth, the topology of the land. You can see the ocean. It’s pretty amazing.鈥�

The OIT team will track down the balloon to recover its payload, likely in the Cascades southeast of Salem. An earlier test run that launched from Detroit Lake ended with the balloon falling near Mount Hood and landing in a tree, Eccles said. The teams use GPS trackers to find the balloons.

Ten students from a variety of engineering disciplines are helping out, Eccles said.

鈥淚t really crosses the breadth of the kinds of courses we offer at Oregon Tech, and it’s a great hands-on learning opportunity,鈥� Eccles said.

TIMING IS EVERYTHING

Engineering students from PSU will launch four weather balloons armed with a variety of cameras for their participation in the NASA cross-country video project.

The biggest balloon will reach 120,000 feet or higher and provide streaming video of the event. The other balloons will reach heights between 60,000 and 90,000 feet and take still photos, which will be combined with the video to create a panorama of the entire eclipse path.

The largest of the balloons will be outfitted with a small cylindrical box containing a streaming camera, a small computer, a custom mother board and a GPS tracking device. Small transmitting devices tied to a wire on the balloon will send the images back to earth, where the video will be broadcast.

Students from Montana State University, which has a program specializing in high altitude balloons, helped build the eight-pound apparatus for the large balloon.

The smaller balloons will carry five-pound payloads that include still-photography cameras and computers . In order to keep the payloads as light as possible, the cameras will be fitted into cases that were produced on a 3-D printer.

鈥淓very pound we save means we can go another 10,000 feet higher,鈥� said Mark Weislogel, a PSU professor of mechanical engineering. 鈥淭here should be almost 200,000 images.鈥�

Grants from NASA covered the majority of the $20,000 total cost to equip the four balloons.

Because the still cameras won’t transmit photos, the students will race to track down the smaller balloons and recover the images. Once a balloons pops or the gas leaks out, the camera package will begin a free fall toward earth. At approximately 50,000 feet a parachute will open to slow the descent and allow the camera to land safely on the ground.

Despite the students’ careful planning, there are still some hiccups that could occur. Wind, for example, could complicate the launch and hamper finding the cameras after the eclipse.

鈥淲e can control (the balloon) by how much gas we put in it,鈥� said Rhiana Mungin, a senior engineering student who’s serving as project manager for the PSU effort. 鈥淢aking sure we have the right amount of gas in the balloon is very dependent on having still air.鈥�

While wind would be bad, rain would be worse.聽 If a balloon gets wet on the ascent, the moisture will freeze as it travels through the atmosphere. That could affect the crucial timing of the balloon.

鈥淩ain on the balloon affects the weight,鈥� Weislogel said. 鈥淭hen you get the weight wrong, and it accelerates when you get through the clouds and it goes faster than you intend it to go.鈥�

Getting to the still cameras once they land also could be a challenge for the students.

鈥淲e are going to be fighting the traffic,鈥� Mungin said. 鈥淭he plan is to stage people downwind to be close to the balloon.鈥�

Assuming the weather cooperates and the cameras are retrieved, Weislogel believes the experiment will result in some amazing photos of a rare occurrence.

鈥淚t’s very likely that we will get some sweet images,鈥� he said.

The colleges’ video will be streamed .