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Autonomous ! CME! Detection ! FOR ! Heliospheric! Imager 2: ! !
1! 2
Lauren Biddle1, Tim Howard2 !
Coronal Mass Ejections!
Leading Edge!Effect Earth’s magnetosphere!!Disrupts Radio Transmission!!Damage to satellites and power grids!!Airliner passengers at risk!!
SOHO/LASCO C3
SMEI!
Written by previous REU students!!analyzed data from !the Solar Mass Ejection Imager!(SMEI)!!Images provided an entire view of the !“sky”!!Has since been decommissioned. ! !
Image taken May, 2003!
The images used for the program used as the basis for the design of our newest leading edge detection
method!
CLED_S!Data were extremely noisy!!² Hot pixels!² Zodiacal light!² Stars/planets!² moon!² Shutters!² magnetosphere !
Resulted in !false positives!
Proof of concept:!!It can be done better!
STEREO!
Images generated from stereo-‐ssc.nascom.nasa.gov
A!B!
SECCHI!S un !E arth !C onnection !C oronal and !H eliospheric ! I nvestigation!
Images from stereo.gsfc.nasa.gov
SECCHI!
Images from stereo.gsfc.nasa.gov
Heliospheric! Imager 2!
FOV!
HI!
Earth!A geometrical representation of the HI-2B FOV!
Defise et al. (2001)
earth!
Elon!
PA!
Heliospheric! Imager 2!
PA!
Elon!
CLED_HI !
Utilizes IDL SolarSoft routines! and CLEDS techniques to! isolate the coordinates of! the leading edge of a CME!
CME Leading Edge Detection for Heliospheric Imagers!
CLED_HI !
Elon
gaCo
n
PosiCon Angle Tappin et al. (2012)
1! After rotating coordinates, !stack images into a cube !
CLED_HI !
El
on
ga
tio
n!
time!
“J-Map”!
!Note the log scale!
Liu et al. (2010)
CLED_HI !
CLED_HI !2! Parsing!
CLED_HI !CLED_HI !3! Hough
Transform!
Accumulator space θ-ρ !
Real space!ε- t!
a! b!
c!d!
θ-ρ !ε- t!
e!f!
[A] J-map!![B] ‘Hough transformed’!![C] after the threshold ! is applied!![D] transformed back! into real space!![E] resultant image ! from edge detection! routine!![F] final j-map with ! intensity mask!tappin et al. (2012)!
SMEI (Solar mass ejection imager)
CLED_HI !CLED_HI !
advantages!
reduces bias from subjectivity of human perception!
CLEDHI provides consistency in the identification of CMEs!
Can assist in the enhancement of space weather prediction tools!
3D models!One example:!
Tappin-Howard Model!
Earth!
TH Model!
Can use leading edge coordinates from HI!!Returns CME’s structural and kinetic information ! !² Location!² Trajectory!² Speed!² Structure!!!Fits model using geometric relations!!Estimate arrival time and speed!Tappin & Howard (2009)
Future Work!Earth will be out of FOV
Projected position on January 1, 2013
can be used with hi-1 images as well!
can be made for precise for the scientific understanding of CMEs!
Easily Adaptable:!
adaptable to the next generation of Heliospheric imagers !
Recap!² CLEDHI is a
for HI-2, based off of CLEDS, designed for SMEI images!
² CLEDHI’s methods utilize to
identify a cme !
when identifying and classifying cmes !
² Leading edge coordinates
for space weather prediction!
for scientific research and future generations of Heliospheric Imagers!
Thank You!
Special thanks to:!
² My advisor, Dr. Tim Howard!
² Marty, Erin and the entire! LASP REU program!
² NSF !
References!Defise, J.-‐M., Halain, J.-‐P., Mazy, E., et al. 2001, , 4498, 63 !Tappin, S.J., & Howard, T.A., 2009, Space Sci. Rev., 147, 55-‐87 Tappin, S. J., Howard, T. A., Hampson, M. M., Thompson, R. N., & Burns, C. E. 2012, Journal of Geophysical Research (Space Physics), 117, 5103