Grade 7 & 8 Students Send Balloon into Space

A styrofoam cooler from 7-Eleven? Creative Intermediate School students fitted this $6.00 item with a weather balloon, a parachute, and string. They drilled a hole in the side and mounted a small camera, and lastly dropped in a GPS-enabled cell phone. The students, who have been planning this mission over the past year, launched their cooler and its camera 20 miles above the earth's surface to capture images and video of the atmosphere as it dissipates into the blackness of space.

Research showed that temperatures could reach -70 degrees Fahrenheit. As a countermeasure, chemically-powered hand warmers were added as a heat source and the cooler was filled with newspapers as insulation. Lithium batteries capable of withstanding the extreme temperatures were used to power the electronics. The students loaded special firmware onto the Canon camera and programmed it to shoot three pictures and then 10 seconds of video each minute. A tracking application was added to the cell-phone; it sent its location back to a web site every 30 seconds.

Because the balloon would be in the air for three to four hours and winds aloft could easily reach 100 mph, the students needed to choose their launch site carefully. At 7 am on Saturday, June 6, the students gathered in the robotics lab and began to check the latest forecasts. Using trajectory modeling software, they predicted that a launch from Chambersburg, Pennsylvania, would result in the balloon landing somewhere in the countryside 20 miles northwest of Baltimore.

Three hours later, they reached a suitable site and began final preparations. Prior calculations showed that the balloon and helium would need to generate approximately 1,800 grams of free-lift if it was to rise quickly into the atmosphere. A last minute decision to add a Cliff bar to the payload, however, threw these numbers off a bit. After some discussion, the students settled on keeping the free-lift at 1,800 grams and launching with a reduced rate of ascent. When it was filled, the balloon measured about five feet in diameter. Ultimately, it would expand to about 26 feet in diameter and reach an altitude of approximately 105,000 feet before bursting.

After checks and rechecks, the balloon was finally released from its earthly tethers. It quickly rose into the sky and was out of sight within minutes. The students began monitoring the balloon's flight on an iPad loaded with the tracking software. Eight minutes into the flight, however, the phone was too high to continue communicating with the ground-based cell towers, and the long wait for renewed communication began.

Gettysburg was along the projected flight path, so a stop for lunch and visit to the battlefield filled in the next several hours, at which point a routine check of the iPad delivered the good news and the bad. The good news was that Google satellite images showed the payload was in the middle of a large field. The bad news was the balloon had flown over the Chesapeake Bay and the field was located on the Eastern Shore! Many, many miles separated the students from the camera and its cache of photos. A four-hour trek began.

As dusk approached the students finally reached a small town near the landing site. Cell-phone service needed to locate the payload had become spotty and they hoped to find an Internet connection. Alas, none was available, but a Starbucks 12 miles away offered hope. All were concerned, however, that the travel time to and from would consume the remaining daylight. Left with no alternative, they set out. Miraculously, five minutes into the trip, cell coverage improved enough to get a fix. They were within a mile of the cooler! Using the iPad, it was possible to find a route and watch path of the vehicle as it approached the balloon.

The vehicle rounded a couple of farm buildings and the field came into view. Way out in the middle, the orange parachute was just visible! A hurried run across the field revealed that the cooler was still intact. After a quick unpacking and several nervous moments of frantic button pushing, the first pictures appeared. There were hundreds. After much scrolling, photos of the balloon at the apex came into view. They were glorious! The blackness of space was clearly contrasted against the thin blue ribbon of our atmosphere as it followed the curve of the earth. Mission accomplished!