There have been downs, but also ups…
The launch crew working hard outside the Lawrence Hall of Science to get the balloon ready to launch. We went through our checklists, and put our practice to good use–with a view!
Our weather balloon drifts up from our launch site at Lawrence Hall of Science.
The last few weeks, our skill building math and science work has built toward the launching of a weather balloon and payload, equipped with a camera set to film our trip to near space. This has been a huge undertaking, in collaboration with the Blue Band. Hence the radio silence.
First, we dropped eggs, trying to figure out how fragile an egg is, and developing strategies to record our data.
Solin records her data for egg drops at different heights. We realized that in order to discern the maximum height to drop an unprotected egg, we would need to start low.
Then, we moved on to egg protection strategies, working up from dropping our eggs first at table height, and finally from the roof!
Sakira used some foam scraps to build a box and protect her egg. But, when the box hit the ground, it came open, the egg rolled out and cracked!
Rebecca and Sakira working on their egg drop packages at the Orchard. We spent a few days co-working with the Blue Band, and a lot of great cross-pollination happened. Check out those pool noodles! Rebecca devised a way to cut the pool noodle into segments and then reassemble, so that she could nestle the egg inside–cozy!
Devlin puts some finishing touches on his pentagonal prism, making sure to secure the egg in place with tape inside the box, his innovation for protecting the egg.
Reyahn’s egg drop package gets dropped from the roof. And the egg made it!
All of this was to get a feel for how our package would drop to earth, and how we would protect the delicate technology inside. Our goal, after all, would be to take pictures on the earth from the stratosphere, and we didn’t want out camera to get smashed upon reentry!
This was a fun, silly and practical introduction to our project. Then, we moved on to some of the other challenges of our launch: figuring out how much our payload would weigh, calculating the volume of helium necessary to lift the payload and carry it far enough–but not too far, and planning for tracking down and retrieving the package, so that we could see the pictures we took. We decided that these three problems would make three teams. Blue would take on calculating the helium and constructing the payload, and Yellow would predict the path of the balloon, and plan for retrieval.
But first, Josh Myers (Calvin’s dad!) came in as an expert on high-altitude ballooning (HAB). Thank you SO MUCH Josh!
Josh gave us such a good rundown of what to plan for, what to expect, and the risks associated with our project. It helped the kiddos realize the scope of the project, and got them super pumped to send things into space.
And we got to work! The Yellow Banders started small, first laying out our block, and comparing the distance across the block “as the crow flies” (aka the hypotenuse) and around, that a human would have to walk.
Sakira points out Charle’s Chocolates on our map of our block.
While proving a relationship between the length of the two sides and the hypotenuse was super hard, we were able to make the connection to our flight: the “crow flies” distance, or hypotenuse, was a metaphor for the path our balloon would travel. The two sides of the block, that a human would walk, represented our driving distance to retrieve the balloon. And they would be very different.
Each morning, we worked with a map showing the predicted path of the balloon. Using the scale, Yellow Banders predicted about how far the balloon would travel. Then, they highlighted the roads we would travel on the map, and measured about how far we would travel.
Emilio works on dividing the path of the balloon into segments the same length as the scale of the map, and then counting up by 5s to approximate the distance travelled by the balloon.
Same map, different routes. Devlin thought we should take I-5, Oscar thought we should take 130 to retrieve the balloon out in the central valley.
And then, the day arrived. We had prepared all we could prepare; it was time for the rubber to meet the road, as my mom would say. Below are some of my favorite pictures from the day. Please check out our Flickr to see more (and video too!).
Sakira, Isaac, Reyahn and Ronan carefully (palms up!) hold the balloon for initial inflation.
Reyahn and Soleil work together to hold the positive lift scale down to the ground while we inflate the balloon. We needed to inflate the balloon with a specific amount of lift, which also meant a specific volume of helium, so that the balloon would travel far enough–but not too far!
Solin steps up to feel the pull of the balloon up. Since helium has a lower molecular weight than the air we breathe, and is less dense, it rises in our atmosphere. It is left over from the formation of the earth, trapped inside pockets deep underground. New helium is made in the sun when hydrogen atoms collide!
Sadie ties off the filled balloon. This moment was a real nail-biter, but you wouldn’t have thought so from Sadie’s calm, steady hand, twisting and wrapping one rubber band after another.
Oscar and Tamasen gazed the travel of the balloon, up and away, for as long as they could. It drifted south, and faded to a pale white dot as it rose.
Several brave souls jumped into cars to chase down the balloon–what an adventure! We recovered the balloon, the payload and all of the footage. Come check it out at our arc presentation next Thursday!