Studying a Total Solar Eclipse in Multiple Wavelengths from a Near-Space Platform

The total solar eclipse of August 21, 2017, gave the high-altitude ballooning community an exceptional opportunity to study lighting conditions in the stratosphere during a total solar eclipse across multiple portions of the spectrum. Sensors on balloon platforms flown in Oregon and Nebraska measured changes in the sky’s overhead intensity at wavelengths ranging from 940 nm (Infrared A, also know as near infrared (NIR)) to 280 nm (Ultraviolet B, also called UVB) during partial eclipse and totality. The moon’s shadow was imaged in near infrared and the Earth’s horizon was imaged in thermal infrared, also known as far infrared (FIR). Intensity measurements at various wavelengths were made using Neulog Light, UVA, and UVB modules, as well using as a LED-based photometer (a Forest Mims design) to study the intensity of eight colors spanning the spectrum from 940 nm infrared to the violet/ultraviolet boundary (400 nm). A Mobius ActionCam was modified for recording NIR, while blocking visible light. A microcontroller/servo combination was use to trigger a Seek Reveal thermal camera for the horizon experiment. Preliminary analysis suggests that the sky’s overhead intensity shows no apparent effect based on wavelength – a somewhat unexpected result. Swinging of the photometer suggests that future measurements should incorporate a sun sensor. The NIR images of the Moon’s shadow are very clear – NIR light is more effective at penetrating the haze of the atmosphere than visible light. There is no evidence in the thermal imager of the eclipse shadow affecting the surface temperature of the Earth

Eclipse-Ballooning 2017: The U of MN – Twin Cities Experience

The stratospheric ballooning team at the U of MN – Twin Cities started working on eclipse-ballooning in the fall of 2013, even before the Montana Space Grant announced their plan to organize a national Eclipse Ballooning Project. Our team promptly signed up to assist their effort, and have been heavily involved ever since. This presentation will discuss our eclipse-ballooning efforts and progress over the past 4 years. Our experiences include experimenting with a GoPro-based video-telemetry system (which ultimately was not as successful as Montana’s Raspberry-Pi-based system), adopting (then helping test, modify, and teach other teams to learn to use) the Montana telemetry system, practicing with up-range and down-range ground station placement, developing and testing passive anti-rotation devices and active camera-pointing devices to improve video quality, landing two eclipse-telemetry systems in Minnesota lakes one week before the eclipse (ouch!), flying five balloon stacks during the eclipse from near Grand Island, NE, and organizing/hosting AHAC 2017. We will also discuss ways in which we have already begun to use the telemetry equipment for non-eclipse balloon missions. The eclipse project has greatly expanded our HAB network and ballooning capabilities in multiple different directions, and will continue to strongly influence our stratospheric ballooning program for years to come

Eclipse-Ballooning 2017: The U of MN – Twin Cities Experience

The stratospheric ballooning team at the U of MN – Twin Cities started working on eclipse-ballooning in the fall of 2013, even before the Montana Space Grant announced their plan to organize a national Eclipse Ballooning Project. Our team promptly signed up to assist their effort, and have been heavily involved ever since. This presentation will discuss our eclipse-ballooning efforts and progress over the past 4 years. Our experiences include experimenting with a GoPro-based video-telemetry system (which ultimately was not as successful as Montana’s Raspberry-Pi-based system), adopting (then helping test, modify, and teach other teams to learn to use) the Montana telemetry system, practicing with up-range and down-range ground station placement, developing and testing passive anti-rotation devices and active camera-pointing devices to improve video quality, landing two eclipse-telemetry systems in Minnesota lakes one week before the eclipse (ouch!), flying five balloon stacks during the eclipse from near Grand Island, NE, and organizing/hosting AHAC 2017. We will also discuss ways in which we have already begun to use the telemetry equipment for non-eclipse balloon missions. The eclipse project has greatly expanded our HAB network and ballooning capabilities in multiple different directions, and will continue to strongly influence our stratospheric ballooning program for years to come