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CACTus LASCO level zero CME catalog
ResourceID
spase://NASA/Catalog/SOHO/LASCO/CACTus/CME_level_zero
Description
The catalog of autonomously detected CMEs in image sequences from LASCO (Large Angle Spectrometric Coronagraph). The crux of the software is the detection of CMEs as bright ridges in (time, height) maps using the Hough transform. The next step employs clustering and morphological closing operations to mark out different CMEs. The output is a list of events, similar to the classic catalogs, with starting time, principle angle, angular width and velocity estimation for each CME. In contrast to catalogs assembled by human operators, these CME detections can be done without any human interference on real-time data 24 h per day (see http://sidc.oma.be/cactus for the real-time output with data covering the last 4 days). Therefore the detection is not only more immediate, but, more importantly, also more objective. Experimental results on real-time data show that the developed technique can achieve excellent results in measuring starting time and principal angle and good results for the angular width and velocity measurement compared to the CMEs listed in the catalog. Its overall success rate is presently about 94%.
Metadata Rights
CC0-1.0:
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions. The actual data/software may be subject to a different license.
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Details
Version:2.7.1
Catalog
ResourceID
spase://NASA/Catalog/SOHO/LASCO/CACTus/CME_level_zero
NamingAuthority
SMWG
ResourceType
Catalog
ResourceHeader
ResourceName
CACTus LASCO level zero CME catalog
ReleaseDate
2026-02-02 13:10:24Z
RevisionHistory
RevisionEvent
ReleaseDate
2025-01-01 12:00:00
Note
Only known prior ReleaseDate of the metadata
RevisionEvent
ReleaseDate
2026-02-02 13:10:24Z
Note
Added MetadataRightsList. Updated to 2.7.1. Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. ZCB
Description
The catalog of autonomously detected CMEs in image sequences from LASCO (Large Angle Spectrometric Coronagraph). The crux of the software is the detection of CMEs as bright ridges in (time, height) maps using the Hough transform. The next step employs clustering and morphological closing operations to mark out different CMEs. The output is a list of events, similar to the classic catalogs, with starting time, principle angle, angular width and velocity estimation for each CME. In contrast to catalogs assembled by human operators, these CME detections can be done without any human interference on real-time data 24 h per day (see http://sidc.oma.be/cactus for the real-time output with data covering the last 4 days). Therefore the detection is not only more immediate, but, more importantly, also more objective. Experimental results on real-time data show that the developed technique can achieve excellent results in measuring starting time and principal angle and good results for the angular width and velocity measurement compared to the CMEs listed in the catalog. Its overall success rate is presently about 94%.
Contacts
Role
Person
StartDate
StopDate
Note
1.
Author
spase://SMWG/Person/David.Berghmans
2.
Author
spase://SMWG/Person/Eva.Robbrecht
3.
MetadataContact
spase://SMWG/Person/Olga.Y.Uritskaya
InformationURL
URL
https://www.sidc.be/cactus/
Description
CACTUS autonomously detects coronal mass ejections (CMEs) in image sequences from LASCO or SECCHI. The output of our software is a list of events, similar to the classic catalogs, with principle angle, angular width and velocity estimation for each CME. In contrast to catalogs assembled by human operators, these CME detections by software can be faster, which is especially important in the context of space weather, and possibly also more objective, as the detection criterion is written explicitly in a program.
The CME list is automatically generated by CACTus. There is no human intervention or supervision at this stage. Therefor we ask to use caution when using the data for statistical purposes.
When any of this data is used, please cite one of the following publications:
1. Robbrecht, E., and D. Berghmans. "Automated recognition of coronal mass ejections (CMEs) in near-real-time data." Astronomy & Astrophysics 425.3 (2004): 1097-1106.
Astrophysical Journal 691 (2009)
2. Robbrecht, E., D. Berghmans, and R. A. M. Van der Linden. "Automated LASCO CME catalog for solar cycle 23: are CMEs scale invariant?." The Astrophysical Journal 691.2 (2009): 1222.
AccessInformation
RepositoryID
spase://SMWG/Repository/SIDC
AccessURL
URL
https://www.sidc.be/cactus/catalog.php
Format
HTML
InstrumentIDs
spase://SMWG/Instrument/SOHO/LASCO
PhenomenonType
CoronalMassEjection
TimeSpan
StartDate
1997-05-17 12:34:56
StopDate
2015-10-31 12:34:56
Parameter #1
Name
CME
Description
CME number
Support
SupportQuantity
Other
Parameter #2
Name
t0
Description
onset time, earliest indication of liftoff
Support
SupportQuantity
Temporal
Parameter #3
Name
dt0
Description
duration of liftoff (hours)
Support
SupportQuantity
Temporal
Parameter #4
Name
pa
Description
principal angle, counterclockwise from North (degrees)
Support
SupportQuantity
Positional
Parameter #5
Name
da
Description
angular width (degrees)
Support
SupportQuantity
Positional
Parameter #6
Name
v
Description
median velocity (km/s)
Support
SupportQuantity
Velocity
Parameter #7
Name
dv
Description
variation (1 sigma) of velocity over the width of the CME
Support
SupportQuantity
Other
Parameter #8
Name
mindv
Description
lowest velocity detected within the CME
Support
SupportQuantity
Velocity
Parameter #9
Name
maxdv
Description
highest velocity detected within the CME
Support
SupportQuantity
Velocity
Parameter #10
Name
halo?
Description
II if da>90, III if da>180, IV if da>270, indicating potential halo/partial halo CME
Support
SupportQuantity
Other