Rockets launched by a Clemson University-led research team could provide insight into how winds and energy from the Earth’s lower atmosphere affect the upper atmosphere, which can impact satellite technology including navigation and communications here on Earth.
The Vorticity Experiment, or VortEx for short, launched two sounding rockets into the mesosphere and lower thermosphere from Andøya Space in Norway, in March, looking for giant swirls (vortices), shifting winds (shears) or other patterns of vorticity.
Affecting the globe
These vortices may be critical to upper atmospheric weather patterns affecting the globe. Understanding the interplay between solar storm events, which are guided by the Earth’s magnetic field, and upper-altitude winds and waves is essential as the world relies more on satellite technology.
The researchers want to learn how high-altitude winds produce, guide or absorb buoyancy waves, which occur when a gust or disturbance kicks denser air upwards into a lower-pressure region. Buoyancy waves often come from approaching storm fronts or winds hitting tall mountains and being sent upwards. As the buoyancy waves move upward and pass through stable layers of the atmosphere, computer models have shown they can form giant swirls of air, or concentric ripples like in a pond when a rock is thrown into the water.
“It’s fundamental research to understand the weather patterns at these heights,” said Gerald Lehmacher, an associate professor in the Department of Physics and Astronomy and principal investigator for the VortEx mission. “In the broadest sense, this experiment is about learning about the fate of buoyancy waves at the edge of space.”
Scientists believe the vortices are tens of miles long, making them too large to measure with conventional approaches. Lehmacher designed VortEx to measure winds at widely separated locations to overcome this limitation.
The proposal Lehmacher and his team submitted to NASA was approved in 2019, with an expected launch in 2021. COVID delayed the launch until this year. The team had a nine-day window, but inclement weather during the first days of the window prevented them from launching any rockets.
On March 23, the researchers launched two sounding rockets. The first rocket was launched at 9 p.m. and reached a height of 149 kilometers. Two minutes later, the second rocket was launched and reached 363 kilometers. The high-flying rocket dispensed tracers into the atmosphere, which formed luminescent trails like those used in fireworks and are visible from the ground. The trails are swept apart and distorted by the high-altitude winds, which allows researchers to “see” and measure the wind. Several researchers, graduate students and technicians from Clemson University were deployed at remote camera sites and onboard a NASA aircraft. The low-flying rocket measured air density, temperature and ionospheric particles.
VortEx also used ground-based radar, lidar and imaging systems to detect buoyancy waves from below.
Researchers are now analyzing the data.
“Ultimately, the goal is to better understand and forecast the atmosphere in these regions,” Lehmacher said.
Upper atmospheric weather affects global positioning system navigation and communication signals. Current computer models of upper atmospheric weather struggle to account for the effects of buoyancy waves. Lehmacher said knowledge of vorticity could be essential to better space weather forecasts because vorticity may be more predictable than buoyancy waves themselves.
The College of Science pursues excellence in scientific discovery, learning and engagement that is both locally relevant and globally impactful. The life, physical and mathematical sciences converge to tackle some of tomorrow’s scientific challenges, and our faculty are preparing the next generation of leading scientists. The College of Science offers high-impact transformational experiences such as research, internships and study abroad to help prepare our graduates for top industries, graduate programs and health professions. clemson.edu/science
Get in touch and we will connect you with the author or another expert.
Or email us at firstname.lastname@example.org