Sun ID: 4167

The Big CME that Missed Earth

Visualizations by Tom Bridgman Released on July 23, 2014

July of 2012 witnessed the eruption of a very large and fast solar coronal mass ejection (CME) (see NASA STEREO Observes One of the Fastest CMEs On Record and Carrington-class CME Narrowly Misses Earth ). While not directed at Earth, it was sufficiently large that it could have seriously disrupted the global electrical infrastructure. The event did impact STEREO-A of NASA's heliophysics fleet which provided a host of measurements (see Sentinels of the Heliosphere).

One of the conditions which contributed to the high speed of this event is that two smaller CMEs were launched a little earlier, and these events cleared out much of the solar wind material, leaving little to slow the outflow of the July 23 event (UTC).

In the visualizations below, generated from the Enlil space weather model, green represents particle density, usually protons and other ions. In green, we see the Parker spiral moving out from the sun generated by the sun's current sheet (Wikipedia). Red represents particles at high temperatures and shows the CME is hotter than the usual solar wind flow. Large changes in density are represented in blue. These three colors sometimes combine to tell us more about the characteristics of the event (noted in the 3-color Venn diagram below).

However, if this CME had struck Earth's magnetosphere, which has a much stronger magnetic field, the changing magnetic field would induce much larger voltages in systems with long electrical conductors, such as power lines that run over long distances. These significantly higher voltages can damage power transformers.

Enlil model run of the July 23, 2012 CME and events leading up to it. This view includes a 'top-down' view in the plane of Earth's orbit, as well as a slice perpendicular to the orbit which passes through Earth. We see the previous CME pass Earth, but not the July 23 event.
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The mass density in atomic mass units (AMUs) per cubic centimeter. 1 AMU/cc corresponds to 1 hydrogen ion or atom per cc. IMPORTANT NOTE: This color bar applies to the large movies above.

Enlil model run of the July 23, 2012 CME and events leading up to it. This movie provides a better view of the inner solar system for the CME event. The density color table has been altered accordingly. This view includes a 'top-down' view in the plane of Earth's orbit, as well as a slice perpendicular to the orbit which passes through Earth. We see the previous CME pass Earth, but not the July 23 event.

Due to the higher particle densities in the inner solar system, this density color table applies to the inner solar system movies above. The upper density limit is 100 atoms/cc.

This color table represents how displaying each of the three variables as separate red, green, and blue color ramps combine to identify characteristics in the solar wind and CME.

Enlil model run of the July 23, 2012 CME and events leading up to it. This view includes a 'top-down' view in the plane of Earth's orbit, but rotated so STEREO-A is the focus of the event. The slice perpendicular to the orbit passes through STEREO-A so we can see the July 23 event hit STEREO-A.

For More Information

Science@NASA

Visualization Credits

Tom Bridgman (Global Science and Technology, Inc.): Lead Animator
Dusan Odstrcil (George Mason University): Scientist
M. Leila Mays (Catholic University of America): Scientist
Janet G. Luhmann (University of California at Berkeley): Scientist
Laurence Schuler (ADNET Systems, Inc.): Project Support
Ian Jones (ADNET Systems, Inc.): Project Support

Please give credit for this item to:

NASA's Scientific Visualization Studio, the Space Weather Research Center (SWRC), the Community-Coordinated Modeling Center (CCMC), Enlil and Dusan Odstrcil (GMU), Leila Mays (CUA) and Janet Luhmann (UCB) and NASA's Scientific Visualization Studio.

Short URL to share this page:
https://svs.gsfc.nasa.gov/4167

Mission:
STEREO

Data Used:

Enlil Heliospheric Model also referred to as: Enlil Heliospheric Model

Model - Community Coordinated Modeling Center (CCMC)

MHD solar wind simulation

view all stories where this data set is used

JPL DE421 also referred to as: DE421

Ephemeris - NASA/JPL

Planetary ephemerides

http://ssd.jpl.nasa.gov/?ephemerides#planets

view all stories where this data set is used

Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site.

This item is part of these series:
Space Weather Modeling
The Carrington-Class CME of 2012

Keywords:
SVS >> Solar Wind
GCMD >> Earth Science >> Sun-earth Interactions >> Solar Activity >> Solar Flares
SVS >> Space Weather
SVS >> Hyperwall
SVS >> Heliophysics
SVS >> STEREO
SVS >> Corona
NASA Science >> Sun
GCMD >> Earth Science >> Sun-earth Interactions >> Solar Activity >> Coronal Mass Ejections

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 8.0.0.0.0

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Appeared on "The Today Show", July 26, 2014