#1 3rd Annual ISS Research and Development Conference, June 19, 2014
Mitsuteru SATO(1), T. Ushio(2),
T. Morimoto(3), H. Kikuchi(2), Y. Takahashi(1),
M. Mihara(1), Toru Adachi(4), M. Suzuki(5),
A. Yamazaki(5), U. Inan(6), and I. Linscott(6)
1. Hokkaido University, Japan
2. Osaka University, Japan
3. Kinki University, Japan
4. Meteorological Research Institute, Japan
5. ISAS / JAXA, Japan
6. Stanford University, Stanford, CA, USA
#2 3rd Annual ISS Research and Development Conference, June 19, 2014
・JEM-GLIMS (Global Lightning and sprIte MeasurementS on JEM-EF)
・Lightning and TLEs observation from Japanese Experiment Module (JEM),
Exposed Facility (EF), ISS.
JEM-GLIMS
© NHK
Sprites
【 Objectives 】
1. Nadir observations of lightning and TLEs from ISS/JEM-EF,
2. Identification of sprite spatial distribution and generation mechanism,
3. Global survey of TLE occurrence.
#3 3rd Annual ISS Research and Development Conference, June 19, 2014
Transient Luminous Events (TLEs) :
Lightning-excited transient discharge phenomena in the mesosphere
© NHK
Watch here!!
What is TLEs?
#4 3rd Annual ISS Research and Development Conference, June 19, 2014
Sprite :
One of the occurrence type of TLEs.
© NHK
What is TLEs?
alt. (km)
90
80
70
60
50
• First discovered in 1989.
• Occurring in 50-90 km alt.
• Always excited by strong
cloud-to-ground lightning
discharges
• Most frequently observed.
#5 3rd Annual ISS Research and Development Conference, June 19, 2014
• Occurrence types of TLEs.
What is TLEs?
#6 3rd Annual ISS Research and Development Conference, June 19, 2014
Quasi-Electrostatic (QE) Field Model
The reason determining the horizontal distribution of sprites
is still big mystery since the discovery of sprites.
What is the Generation Mechanism?
[Pasko et al., 1997]
Most of the observational facts
can not be explained only by
the simple QE model.
We need more accurate
generation mechanism
of sprites.
Nadir observation is essentially effective.
#7 3rd Annual ISS Research and Development Conference, June 19, 2014
What is the Occurrence Rates?
Global Occurrence Rates of Lightning
OTD / MicroLab-1 LIS / TRMM
We do not know the global occurrence rates and distributions of TLEs...
ISS is an ideal platform for the lightning and TLE observations.
ISS has 51° orbital inclination. Lighting and TLE observation by
scanning all the local time area!!
#8 3rd Annual ISS Research and Development Conference, June 19, 2014
NOx production by sprites
Global occurrence rates and distributions of TLEs
Chemical Impact of Sprites on Earth’s Atmosphere
What is the Chemical Impact of TLEs?
We can evaluate chemical impact of TLEs on Earth’s atmosphere!!
#9 3rd Annual ISS Research and Development Conference, June 19, 2014
Name ID Specification
CMOS Camera
(optical) LSI
Two CMOS cameras 512x512 pixels, FOV=28.3×28.3, fps = 29 (122, 488),
10 bit resolution,
LSI-1: = 762+/-5 nm, LSI-2: =765-830 nm
Photometer
(optical) PH
6 channel photometers = 150-280 nm, 316+/-5 nm, 337+/-5 nm, 392+/-5 nm,
= 762+/-5 nm, 600-900 nm
fs = 20 kHz, FOV=43, 12 bit resolution
VLF Receiver
(EM) VLFR
1 set of VLF antenna and a receiver f = 1-40 kHz, fs = 100 kHz, 16 bit resolution,
15cm monopole antenna
VHF
Interferometer
(EM) VITF
2 sets of VHF antennas and a receiver fs = 70-100 MHz, 8 bit, patch antenna, baseline=1.5 m
Science
instrument
Handling Unit SHU
Onboard computer Power control, Event triggering, Data acquisition & handling,
Command/telemetry I/F, Data compression
GLIMS Instruments
#10 3rd Annual ISS Research and Development Conference, June 19, 2014
Item Value
Wavelength 765-830 nm (LSI-1)
762+/-5 nm (LSI-2)
FOV 28.3° × 28.3°
Optics F=1.4, f=25mm
Detector CMOS (STAR-250)
Pixel Number 512 × 512
Sensitivity 6.9E-6 W/m2
Resolution 10 bit
Spatial
Resolution
0.4 km/pix
@ ground surface
Time
Resolution
34.5 ms (29fps)
Table. Summary of LSI specification.
LSI
• 2 CMOS cameras (wide-band / narrow-band filter)
• LSI-1 : wide-band filter (lightning)
• LSI-2 : narrow-band filter (TLEs)
Fig. Picture of LSI flight model.
LSI-1
LSI-2
LSI (Lightning and Sprite Imager)
#11 3rd Annual ISS Research and Development Conference, June 19, 2014
10
100
400
O2
ISS altitude
762nm
762nm
Alt. [km] Lightning Spectrum
Sprite Spectrum(N2 1PG)
LSI
#12 3rd Annual ISS Research and Development Conference, June 19, 2014
Item Value
Wavelength 150-280 nm
337+/-5 nm
762+/-5 nm
600-900 nm
316+/-5 nm
392+/-5 nm
PH1
PH2
PH3
PH4
PH5
PH6
N2 LBH
N2 2P(0,0)
N2 1P(3,1)
N2 2P(0,0)
N2 2P(1,0)
N2+ 1N(0,0)
FOV 42.7°
86.8°
for PH1-3,5,6
for PH4
Detector PMT (R7400)
PDD (S1227)
for PH1-3,5,6
for PH4
Sensitivity @SNR=10
0.1E-6 W/m2
10E-6 W/m2
for PH1-3,5,6
for PH4
HV Range 0-1000 V
Resolution 12 bit
Sampling Freq. 20 kHz
Table. Summary of PH specification.
PH • 2 photometer units (PH-U)
• Absolute intensity measurement of
N2 1P, 2P, N2+ 1N emission lines
Fig. Picture of PH Unit #1 (top) and PH Unit #2 (bottom).
#13 3rd Annual ISS Research and Development Conference, June 19, 2014
10
100
400
O3
ISS altitude
Alt. [km]
150-280nm
150-280nm
N2 LBH spectrum of sprites
Atmospheric transmittance
PH
#14 3rd Annual ISS Research and Development Conference, June 19, 2014
Item Value
Freq. Range 1-30 kHz
Resolution 14 bit
Sampling Freq. 100 kHz
Antenna monopole antenna (15cm)
Table. Summary of VLFR specification.
VLFR
• VLF Receiver
• Detection of whistler wave generated by lightning
Fig. Picture of VLFR electronics (top) and VLFR antenna (bottom). Fig. Schematic illustration showing the propagation of whistler waves.
#15 3rd Annual ISS Research and Development Conference, June 19, 2014
VITF
Item Value
Freq. Range 70-100 MHz
Resolution 8 bit
Sampling Freq. 200 MHz
Antenna patch-type antenna
Table. Summary of VITF specification.
• VHF Interferometer (VITF)
• Measurement of VHF pulses excited by lightning
Fig. Picture of VITF electronics (top) and VITF antennas (bottom). Fig. Development of lightning currents derived from VHF interferometer data.
#16 3rd Annual ISS Research and Development Conference, June 19, 2014
GLIMS Instruments
PH-U1
PH-U2 LSI-1
VLFR antenna
Fig. Picture of GLIMS flight model.
SMA connectors for VITF antennas
LSI-2
#17 3rd Annual ISS Research and Development Conference, June 19, 2014
IMAP/VISI REX-J
HDTV
SIMPLE
GLIMS/PH
IMAP/EUVI
GLIMS/LSI
GLIMS/VLFR-ANT
GLIMS/VITF-ANT
GLIMS/VITF-ANT Nadir
JEM-GLIMS and MCE Multi-mission Consolidated Equipment (MCE)
#18 3rd Annual ISS Research and Development Conference, June 19, 2014
JEM-GLIMS was launched by H-IIB rocket and HTV-3 cargo ship 2012
Jul. 21
HTV-3 docked with ISS
Jul. 27
MCE was installed at JEM Exposed Facility (EF)
Aug. 9 GLIMS initial checkout operation started
Sep. 15 Initial checkout operation completed, and
started test observation
Nov. 12
Nominal operation started
Nov. 20 Continuous observation
and data acquisition 2013
Parameter studies for event triggering
Mission Status
2014
#19 3rd Annual ISS Research and Development Conference, June 19, 2014
2013/03/22 22:10:47UT
10km
2012/12/25 12:49:04UT
10km
2013/01/01 19:36:17UT 2013/01/30 04:20:58UT
10km
2013/02/11 02:45:02UT
10km
2013/03/29 13:20:05UT
10km
2013/01/18 17:04:59UT
10km
2012/12/29 00:16:20UT
10km
10km
Period : 2012/ 11/ 20 - 2014/ 01/ 31
3,130 events
JEM-GLIMS Lightning Events
#20 3rd Annual ISS Research and Development Conference, June 19, 2014
South Atlantic
Anomaly (SAA)
Period : 2012/ 11/ 20 - 2014/ 01/ 31
Global Map of Triggered Events
3,130 events
#21 3rd Annual ISS Research and Development Conference, June 19, 2014
South Atlantic
Anomaly (SAA)
Seasonal Variation
Northern Summer (June, July, August)
#22 3rd Annual ISS Research and Development Conference, June 19, 2014
Seasonal Variation
Northern Winter (December, January,
February)
South Atlantic
Anomaly (SAA)
#23 3rd Annual ISS Research and Development Conference, June 19, 2014
20 km
LSI-1 LSI-2
765-830nm 762±5nm
Frame 1 (Ttrigg.=-33ms)
Frame 2 (Ttrigg. = 0ms)
Frame 3 (Ttrigg.=+33ms)
Frame 4 (Ttrigg.=+66ms)
150-280nm
337nm
600-900nm
316nm
392nm
762nm
PH1
PH2
PH3
PH4
PH5
PH6
Trigger 2013/09/28 19:50:40.30580 UT @ Central Africa
Occurrence of TLEs
90 95 100 105 110 115 120 [ms]
Sprite Event / Outline of the Event
#24 3rd Annual ISS Research and Development Conference, June 19, 2014
Frame 2 (Ttrigg. = 0ms)
Frame 3 (Ttrigg.=+33ms)
Subtracted Image LSI-1 Image
Existence of the
fine structures!!
20 km 20 km
Sprite Event / Image Subtraction
#25 3rd Annual ISS Research and Development Conference, June 19, 2014
Sprite Event
2013/12/21 05:08:14.63340 UT @ Mexico, Middle America
Frame 3 (Ttrigg.= +33 ms)
Subtracted Image with LSI-1 Image LSI-1 Image
10 km 10 km
Subtracted image
Detailed horizontal structure of sprites is first identified!!
#26 3rd Annual ISS Research and Development Conference, June 19, 2014
15 km
LSI-1 LSI-2
765-830nm 762±5nm
Frame 1 (Ttrigg.=-33ms)
Frame 2 (Ttrigg. = 0ms)
Frame 3 (Ttrigg.=+33ms)
Frame 4 (Ttrigg.=+66ms)
150-280nm
337nm
600-900nm
316nm
392nm
762nm
PH1
PH2
PH3
PH4
PH5
PH6
Occurrence of TLEs
90 95 100 105 110 115 120 [ms]
2013/09/08 16:57:33.70315 UT @ Southern Australia
Elves Event / Outline of the Event
#27 3rd Annual ISS Research and Development Conference, June 19, 2014
Elves Event / Interpretation
Due to the rapid lateral expansion (<1ms) and thin optical depth of the elves emission, LSI can not image elves (below the sensitivity).
Due to the wide FOV and high sensitivity, PH can only detect elves signal.
FOV of LSI (160km×160km @90km)
iFOV of LSI (0.3km×0.3km @90km)
FOV of PH (42.7° conical)
Elves
Propagation of EMP
Alt.
[km]
410
90
10
GLIMS
Lateral expansion
CG discharge
(r=125km circle @90km)
#28 3rd Annual ISS Research and Development Conference, June 19, 2014
Lightning Whistler
2013/09/09 13:04:07.39706 UT
Lightning emission
Lightning whistler
Time delay from the lightning
can be reasonably explained by
the propagation of whistler
wave with a group velocity (Vg).
Frequency Dispersion
Electrical properties of
lightning discharge.
#29 3rd Annual ISS Research and Development Conference, June 19, 2014
VHF Pulses
2013/05/25 14:50:30.18751 UT Lightning images (LSI)
Light curve data of PH
VHF pulses are mainly emitted by
in-cloud lightning currents.
Detection number of VHF
pulses
Sample waveforms of VHF
pulses
First identification!!
We will estimate source location
using interferometric technique.
#30 3rd Annual ISS Research and Development Conference, June 19, 2014
JEM-GLIMS is continuing nadir observations of lightning &
TLEs from ISS, and it succeeded in detecting thousands of
lighting events since Nov. 2012.
JEM-GLIMS succeeded in detecting sprite and elves events by
the optical instruments.
JEM-GLIMS also succeeded in detecting lighting whistler and
VHF pulses, which enable us to identify the electrical
properties of lightning discharges.
Future Plan
Comparison between GLIMS optical data and GLIMS/VLF and VHF
data to clarify the generation mechanism of sprites,
Identification of seasonal / LT dependences of TLE occurrences.
Conclusion
#31 3rd Annual ISS Research and Development Conference, June 19, 2014
Appendix
#32 3rd Annual ISS Research and Development Conference, June 19, 2014
Global Map of FUV Events
South Atlantic
Anomaly (SAA)
Period : 2012/ 11/ 20 - 2014/ 01/ 31
PH1 Events = 365
Global Distribution of Possible TLEs
#33 3rd Annual ISS Research and Development Conference, June 19, 2014
JEM-GLIMS and MCE
PH Unit1
LSI
PH Unit2
VLF
Antenna
VITF
Antenna #1
GLIMS Main
Instruments
MCE VITF
Antenna #2
©JAXA
GLIMS
• 2-channel CMOS cameras (LSI)
• 6-channel photometers (PH)
• VLF receiver (VLFR)
• 2-sets of VHF receivers (VITF)
#34 3rd Annual ISS Research and Development Conference, June 19, 2014
Item Value
Main Function Power control Data acquisition Event trigger Data compression (HIREW encoding) GPS time synchronization Command, Telemetry I/F (RS422 I/F)
FPGA Xilinx Vertex II
CPU SH2
S-RAM 8MB x 2 for FPGA (temporal data buffering)
8MB for CPU
Mass Memory 128MB (FIFO memory for TLM)
Table. Summary of SHU specification.
SHU SHU (Science instruments Handling Unit)
• Power control (power, A/D)
• Event trigger, data acquisition
• GPS synchronization
• data compression: HIREW (lossless)
• Command and telemetry interface
Fig. Picture of SHU flight model.
#35 3rd Annual ISS Research and Development Conference, June 19, 2014
LSI-1
Image
Frame 2 (Ttrigg. = 0ms)
x (1/α)
ave+5σ
LSI-2
Image
Sprite Event / Image Subtraction
#36 3rd Annual ISS Research and Development Conference, June 19, 2014
Peak intensities of PH light curve data
PH1 (150-280nm)
PH2 (337nm)
PH3 (762nm)
PH4 (600-900nm)
PH5 (316nm)
PH6 (392nm)
98 99 100 101 102 103 104 [ms]
Peak Intensities
150-280nm:
2.02×10-7 [W/m2]
337nm: 2.52×10-4 [W/m2]
762nm: 1.46×10-4 [W/m2]
600-900nm:
1.01×10-2 [W/m2]
316nm: 3.29×10-5 [W/m2]
392nm: 2.88×10-4 [W/m2]
Sprite Event / Absolute Intensity of PH Data
#37 3rd Annual ISS Research and Development Conference, June 19, 2014
Log(Ratio)
337nm / Red(610-750nm) 337nm / Red(600-900nm)
Ratio (337 / Red) Occurrence probability of TLEs
0.68 10 %
1.07 20 %
2.09 40 %
4.47 60 %
11.7 80 %
Sprite Event / Intensity Ratio, Occurrence Probability O
ccu
rre
nce
Pro
ba
bili
ty
Log(Ratio)
Occu
rre
nce
Pro
ba
bili
ty
ISUAL Case GLIMS Lightning Case
[ Adachi et al., AE33A-0317, this meeting ]
#38 3rd Annual ISS Research and Development Conference, June 19, 2014
(337/Red): x 26
100 200 300 400 500 600 700 800 900
Wavelength [nm]
102
101
100
10-1
10-2
10-3
10-4
10-5
Re
lati
ve I
nte
nsit
y R
ati
o
Relative Intensity Ratio toward PH4(600-900nm) Intensity
GLIMS Lightning Event
Analyzed Event
Sprite Event / Intensity Ratio
( 337 / Red ) = x 26 ( 392 / Red ) = x 25
Occurrence Probability of TLEs
80% at (337/Red)=11.7
[ Adachi et al., AE33A-0317, this meeting ]
#39 3rd Annual ISS Research and Development Conference, June 19, 2014
GLIMS
data
ELF
data
40.0 40.2 40.4 40.6 40.8 41.0 [sec]
PH2
NS-comp
EW-comp
NS-comp
EW-comp
Δt = 35.6 ms
(8.5 Mm @ v=0.8c)
Δt = 43.0 ms
(10.4 Mm @ v=0.8c)
Sprite Event / Electrical Properties of Parent CG
Esrange (Kiruna)
Syowa (Antarctica)
40
0
-40 40
0
-40
20
0
-20 20
0
-20
0.0 0.1 0.2 0.3 0.4 0.5 [sec]
4.0
2.0
0.0
[ V
]
[ pT
]
[ pT
]
Possible CG Time = 40.30443 [sec]
↓ Trigger time = 40.30580 [sec]
#40 3rd Annual ISS Research and Development Conference, June 19, 2014
Sprite Event / Electrical Properties of Parent CG
Propagation Paths of the ELF Waves
Distance between sub-satellite point (SSP) and ELF stations
SSP – Esrange = 7.0 Mm
SSP - Syowa = 8.5 Mm
(13.695°E, 5.540°N)
Location of the sub-satellite point (SSP)
Actual distances between SSP and ELF stations are comparable to these derived from propagation time of the ELF waves.
Cross point of the two great circles and sub-satellite point are very close.
Propagation Path @ESR
Propagation Path @Syowa
Esrange
Sub-satellite point (13.695°E, 5.540°N)
Syowa
8.5 Mm
7.0 Mm
Cross point of the two great circles
#41 3rd Annual ISS Research and Development Conference, June 19, 2014
Current Moment Waveform (ESR data)
HΦ(f) : observed magnetic filed spectrum Idl(f) : current moment spectrum I0dl : peak current moment θ : angular distance RE : radius of the Earth h0 : wave reflection height n : mode number ν : propagation coefficient Pm : Legendre polynomial τ : time constant of the lightning current
Charge Moment Change (CMC) Estimation
Current Moment Spectrum
Sprite Event / Electrical Properties of Parent CG
Station CMC
Esrange +1843 [Ckm]
Syowa +1622 [Ckm]
Assumed Current Moment Waveform
Enough to excite sprites!!
Current Moment Spectrum (ESR data)
CMC = +1843 [Ckm]
#42 3rd Annual ISS Research and Development Conference, June 19, 2014
Field-of-view (FOV) of LSI and PH
FOV of LSI and PH
FOV of PH1-3, PH5, PH6(42.7
o, conical)
FOV of LSI(28.7
o x 28.7
o, square)
FOV of PH4(86.8
o, conical)
210 km
210 km
378 km
156 km
#43 3rd Annual ISS Research and Development Conference, June 19, 2014
• PH1 signals are originated from N2 Lyman-Birge-Hopfield (LBH) emission.
• Sprites can emit N2 LBH emission [Gordillo‐Vázquez et al., 2011; Kuo et al., 2007;
Chang et al., 2010].
• Lightning FUV emission may not reach ISS altitude due to the severe O3
absorption. It this event related to TLEs???
Fig. Simulated N2 LBH spectrum of sprite halo
[Gordillo‐Vázquez et al., 2011].
N2 LBH Spectrum of Sprite Halo
Fig. Calculated atmospheric transmittance in the visible range.
FUV Emission and Atmos. Transmittance