A long-exposure
photo taken from the International Space Station shows airglow as bands of
green and red curving around Earth. A flash of lightning appears near the
bottom.
Credits: NASA
On May 21, ground controllers powered down NASA’s AWE (Atmospheric Waves Experiment) instrument, bringing the data collection phase of the mission to a successful and scheduled end, surpassing its planned two-year mission.
Installed on the exterior of the International Space Station since November 2023, AWE studied atmospheric gravity waves, which are giant ripples in the atmosphere caused by strong winds flowing over tall mountains or by violent weather events, such as tornadoes, thunderstorms, and hurricanes. The AWE instrument looked for these waves in colorful bands of light in Earth’s atmosphere, called airglow. Funded by NASA’s Heliophysics Division, AWE investigated how atmospheric gravity waves propagate upward to space and contribute to space weather — conditions in space that can disrupt satellites, as well as navigation and communications signals.
“The AWE mission has proven that our atmosphere is not a ceiling, but a living, breathing ocean in the sky,” said Joe Westlake, director of NASA’s Heliophysics Division at NASA Headquarters in Washington. “For the first time, we can see how a thunderstorm in the Midwest, a hurricane over Florida, or a wind gust over the Andes sends invisible ripples — atmospheric gravity waves — crashing into the edge of space like waves hitting a shoreline. By mapping these ripples from the International Space Station, we’ve discovered that Earth’s weather doesn’t just end at the clouds, instead it reaches out beyond our planet, shaping the space weather that impacts our orbital economy.”
This artist’s
conception depicts the Atmospheric Waves Experiment (AWE) scanning the
atmosphere from aboard the International Space Station, measuring variations in
infrared airglow to track atmospheric gravity waves as they move up from the
lower atmosphere into space.
Utah State
University Space Dynamics Laboratory
During AWE’s
30-month residency on the station, the instrument captured four infrared images
every second, tallying more than 80 million nighttime images, which is when
airglow can be seen. It observed atmospheric gravity waves from numerous
extreme weather events, including a tornado outbreak across the central U.S. in
May 2024 and Hurricane Helene impacting the gulf coast of Florida in September
2024.
“We’ve seen
atmospheric wave signatures associated with major terrestrial events, which
provided a clear example of how intense weather systems can generate measurable
upper-atmospheric responses,” said AWE’s principal investigator, Ludger
Scherliess of Utah State University in Logan.
These events
revealed variations in the types of atmospheric gravity waves created by
different kinds of storms. For example, when AWE viewed atmospheric gravity
waves generated by a thunderstorm in north Texas on May 26, 2024, it saw they
were smaller and more irregular, with a notable asymmetry from north to south,
compared to waves created by storms in the same part of the country earlier
that month.
This image from
AWE shows concentric atmospheric gravity waves caused by a severe weather event
that included a tornado near the U.S.-Mexico border on May 3, 2024. Captured
during orbit 2529 of AWE’s stay on the International Space Station, the image
shows waves spreading across Texas and Mexico in near-perfect circles, a sight
rarely observed with such clarity prior to the AWE mission.
NASA/Utah State
University
It is important
to understand variations in the density of plasma, which is electrically
charged gas, in Earth’s upper atmosphere instigated by atmospheric gravity
waves, because these variations can disrupt radio signals traveling between
satellites and the ground, and from satellite to satellite, degrading the
accuracy and reliability of systems used for navigation, timing, and
communications.
In a recent
study, AWE measurements also revealed the gravity waves with the greatest
influence on the upper atmosphere have small horizontal wavelengths, ranging
from 30 to 300 kilometers, which AWE was specifically designed to measure.
With its
data-collection phase complete, the AWE instrument was turned off to make way
for another science experiment that will take its place on the outside of the
space station. Called CLARREO Pathfinder (Calibration Absolute Radiance and
Refractivity Observatory Pathfinder), the new instrument will take measurements
of sunlight reflected by Earth and the Moon that are five to 10 times more
accurate than those from existing sensors. The exchange of instruments is a key
part of the space station’s mission and versatility as an orbiting laboratory
for various types of research.
As the
International Space Station traveled over the southeastern United States on
Sept. 26, 2024, AWE observed atmospheric gravity waves generated by Hurricane
Helene as the storm slammed into the gulf coast of Florida. The curved bands
extending to the northwest of Florida, artificially colored red, yellow, and
blue, show changes in brightness (or radiance) in a wavelength of infrared
light produced by airglow in Earth’s mesosphere. The small black circles on the
continent mark the locations of cities.
Utah State
University
In the coming
days, a robotic arm on the space station, called Canadarm2, will remove the AWE
instrument from its location. Soon afterward, the AWE instrument will be loaded
into part of a SpaceX Dragon cargo spacecraft that will deorbit and burn up as
it re-enters the atmosphere. However, all of AWE’s observations will ultimately
become available to the public and the scientific community for ongoing
research and discovery.
“Data from AWE
will continue to be made public for both professional researchers and citizen
scientists,” Scherliess said.
Some of this data already is available, including interactive, online visualizations on Utah State University’s website, where AWE’s observations are “painted” in swaths onto a globe or on a map as the space station orbits the planet. Users can rotate the visualizations to view atmospheric gravity waves from different angles.
A still image from an interactive
visualization shows AWE data collected over the Western Hemisphere.
Utah State University
Launched on Nov. 9, 2023, AWE is managed by
the Explorers Program Office at NASA’s Goddard Space Flight Center in
Greenbelt, Maryland. Utah State University’s Space Dynamics Laboratory built
the AWE instrument and provided the mission operations center.
Hear more about AWE by listening to episode
334 of NASA’s Houston We Have a Podcast, recorded on Jan. 26, 2024.
By Vanessa Thomas
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Source: NASA’s AWE Completes Mission to Study Earth’s Effect on Space Weather - NASA Science




No comments:
Post a Comment