NASA Johnson Pilots Chase Moon’s Shadow for Eclipse Science

During the total solar eclipse on August 12th over Europe, scientists sought to unravel a persistent enigma: why the Sun's outer atmosphere, the corona, is significantly hotter than its visible surface. To gather the necessary data, precise timing and location were paramount.

Pilots from NASA's Johnson Space Center commanded the high-altitude WB-57F research aircraft, flying from Ellington Field in Houston to Iceland. This served as their base for operations within the path of totality, providing scientists with an unobstructed view of the Sun's corona.

A total solar eclipse offers a rare chance to study the corona because the Moon momentarily conceals the Sun's bright disk, revealing its fainter outer layers. Observations collected during this fleeting period can significantly advance scientists' understanding of energy and material transfer within the corona and away from the Sun, thereby improving our grasp of space weather phenomena.

Operating at an altitude of approximately 50,000 feet, the WB-57F soared above most clouds, dust, and water vapor that can impede ground-based observations. This altitude minimized atmospheric interference and enabled the scientific instruments to capture infrared wavelengths, which are largely absorbed at lower altitudes in Earth's atmosphere.

Acquiring these observations demanded meticulous coordination between scientists and the flight crew. Prior to the mission, teams precisely calculated the aircraft's trajectory to align with the Moon's shadow as it traversed the North Atlantic.

“Undertaking a mission like this requires a vast team effort. It begins with the science team defining the requirements, and then we collaborate closely with them for months leading up to the mission,” stated Tom Parent, a NASA WB-57F pilot. “We depend heavily on our maintenance crew to service, prepare, and install the instruments on the aircraft, followed by flight testing. It's a monumental team endeavor to get an aircraft like this airborne for imaging and achieving these objectives.”

During the eclipse's totality, NASA WB-57F pilot John Gustine maneuvered the aircraft along the eclipse path to maximize their time within the Moon's shadow, affording scientists the greatest possible opportunity to collect data.

From the rear cockpit, Cary Klemm, the sensor equipment operator for NASA's WB-57F, managed the camera systems. He adjusted focus and exposure settings while tracking areas of interest throughout the period of totality.

With the cameras actively capturing observations during the brief window, every second was critical.

“Each image is another piece of data that could reveal something new about the Sun,” Klemm commented.

The knowledge gained from these observations extends far beyond the eclipse itself. The Sun's corona, composed of plasma shaped by magnetic fields, shares physical processes with phenomena occurring elsewhere in the universe.

“The NASA WB-57F’s unique high-altitude flight capabilities were truly instrumental in providing access to these valuable wavelengths during an eclipse whose path crossed mainly over the ocean in an area where clouds are common,” explained Amir Caspi, principal investigator for the study at Southwest Research Institute in Boulder, Colorado. “We could not have achieved this success without this platform and all the efforts of the many intrepid ground, air, and science crew members.”

The data gathered during the flight will further enable scientists to investigate the Sun and the processes that influence Earth's surrounding space environment.

View images and videos from NASA’s eclipse mission.

---

English Translation:

During the total solar eclipse on August 12th over Europe, scientists aimed to investigate a long-standing mystery: why the Sun's outer atmosphere, the corona, is far hotter than its visible surface. Capturing the necessary data required being in the exact right place at the exact right time.

Pilots from NASA’s Johnson Space Center flew the high-altitude research aircraft, the WB-57F, from Ellington Field in Houston to Iceland. This location served as their base for flying through the path of totality to provide scientists with a clearer view of the Sun’s corona.

A total solar eclipse offers a unique opportunity to examine the corona because the Moon temporarily blocks the Sun’s bright surface, revealing its fainter outer atmosphere. Observations collected during this brief window can help scientists better understand how energy and material move through the corona and away from the Sun, improving our understanding of space weather.

At approximately 50,000 feet, the WB-57F flew above most clouds, dust, and water vapor that can interfere with observations from the ground. The altitude reduced atmospheric interference while also allowing the science instruments to observe infrared wavelengths that are largely absorbed lower in Earth’s atmosphere.

Capturing those observations required careful coordination between scientists and the flight crew. Before the mission, teams calculated where the aircraft needed to be as the Moon’s shadow moved across the North Atlantic.

“Going into a mission like this takes a huge team. It starts with the science team establishing the requirements, and then we work closely with them for months leading up to the mission,” said Tom Parent, NASA WB-57F pilot. “We rely heavily on our maintenance team to get the instruments serviced, prepared, loaded onto the aircraft, and flight tested. It’s a huge team effort to get an aircraft like this up there to image and achieve these objectives.”

During totality, NASA WB-57F pilot John Gustine positioned the aircraft along the eclipse path to maximize time in the Moon’s shadow and give scientists as much opportunity as possible to collect data.

From the back seat, Cary Klemm, sensor equipment operator for NASA’s WB-57F, controlled the camera systems, adjusting focus and exposure times while tracking features of interest throughout totality.

With the cameras capturing observations throughout the brief window, every second mattered.

“Every image is another piece of data that could reveal something new about the Sun,” Klemm said.

What scientists can learn from those observations reaches far beyond the eclipse itself. The Sun’s corona is made of plasma shaped by magnetic fields, and many of the same physical processes occur elsewhere in the universe.

“The NASA WB-57F’s unique capabilities of high-altitude flight were truly crucial in providing access to these valuable wavelengths during an eclipse whose path crossed mostly over the ocean in an area where clouds are common,” said Amir Caspi, principal investigator for the study at Southwest Research Institute in Boulder, Colorado. “We could not have achieved this success without this platform, and all of the efforts of the many intrepid ground, air, and science crew members.”

The data gathered during the flight will give scientists another opportunity to investigate the Sun and the processes that influence the space environment around Earth.

View images and videos from NASA’s eclipse mission.