Lightning and Sprite Observations (LSO-B, LSO-F, LSO-H, LSO-S), Four Investigations
Research Area: Earth Remote Sensing
Expedition(s): 3, 5, 8, 9
Principal Investigator(s): ● Elisabeth Blanc, French Alternative Energies and Atomic
Energy Commission, Bruyeres le Chatel, France
RESEARCH OBJECTIVES
The Lightning and Sprite Observations
(LSO) investigation observes sprites
during storms to determine the energy
emitted and compare this to nightly
emissions of lightning, as well as
determining frequency of the
phenomena. Sprites are a
meteorological phenomenon, which
have the appearance of a luminous
glow above lightning storms between
50-90 km above the Earth’s surface.
RESULTS
During 19 hours of effective
observations, 180 flashes were
captured, and several possible sprites
were identified, demonstrating the
effectiveness of the differentiation
method. In addition, during sunset and
sunrise when the lower atmosphere is
dark, LSO observed the airglow of the
secondary ozone maximum at about 90
km modulated by gravity wave activity.
At the end of the Odissea mission (2002), LSO observed 60 transitory events with the camera in
the visible and near infrared and 13 events with both cameras. The ratio of the intensities
received by both cameras was about 3 to 5%. The event is correlated to lightning activity
measured at ground by the Japan Lightning Detection Network.
On the LSO data, 15 sprites were observed on a surface of 200x200 km within 19 hours of
effective measurements over continents. During these 19 hours, about 1000 lightning occurred,
according to LIS statistics. This corresponded to 1-3 sprites for 100 lightning flashes. This value
was in agreement with the values generally given of 1 sprite for 100 to 500 lightning, even if the
number of effective observation hours of LSO was still low for reliable statistics. It is necessary
to obtain additional measurements to validate these first statistics.
First observation of sprite from the nadir by Lightning and Sprite
Observations. The color scale indicate the measured intensity 1) Top :
filtered camera 2) Middle : camera in the visible and near IR, 3) Bottom :
ratio of both camera intensities in percent. The event at the right is an
intense lightning while both events on the left are sprites. They are
differentiated by the ratio of the intensities measured by both cameras,
most intense for sprites than for lightning. ESA image.