# Coronal Mass Ejection (DD-091)

> A coronal mass ejection (CME) is a large expulsion of plasma and magnetic field from the Sun's corona. According to NOAA's Space Weather Prediction Center, a CME can eject billions of tons of coronal material carrying an embedded magnetic field. When one reaches Earth it can trigger a geomagnetic storm, which can disrupt radio communication and satellites and push auroras to lower latitudes than usual. Wikipedia gives an average mass of about 1.6 × 10^12 kg, noting that estimates are lower limits. The footage shows solar imagery, Earth's magnetic field, city lights from orbit and auroras, with the presenter.

- Department: Space (also Science)
- First published: 2023-11-24
- Last updated: 2023-11-24
- Permalink: https://detailenjoyer.com/case/coronal-mass-ejection/
- Original Reel title: Coronal Mass Ejection ☀️
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## Quick facts

- **DD-091-F01**: CMEs are eruptions of plasma and magnetic field from the corona. _(Write-up · Exhibit A (From the corona))_
- **DD-091-F02**: A CME can carry billions of tons of material. _(Write-up · Exhibit B (Billions of tons))_

## Write-up

The Sun sometimes throws off billions of tons of itself. A CME aimed at Earth can stir up geomagnetic storms and auroras.

1. **From the corona**: CMEs are large expulsions of plasma and magnetic field from the Sun's corona.
2. **Billions of tons**: A CME can eject billions of tons of material, per NOAA.
3. **Average mass**: Wikipedia gives an average of about 1.6 × 10^12 kg, as a lower limit.
4. **Geomagnetic storms**: Earth-directed CMEs can cause geomagnetic storms.
5. **Auroras**: Those storms can push auroras to lower latitudes.

## Related case files

- [Solar Prominence (DD-038)](https://detailenjoyer.com/case/solar-prominence/): I paired it with another eruption from the Sun's surface

## Reel vs. record

- **Note**: 'Several Mount Everests combined': I couldn't find a source for this comparison. The sourced figure is billions of tons, about 1.6 × 10^12 kg on average, so I left the mountain comparison out of the write-up.

## Video: Coronal Mass Ejection: The Sun Sometimes Throws off Billions of Tons of Itself

- Duration: 39.0 s · Published: 2023-11-24
- File: https://detailenjoyer.com/assets/videos/C0CZt7MJIl2.mp4

### Transcript

Coronal Mass Ejections or CMEs, are massive bursts of solar wind and magnetic fields rising above the solar corona or being released into space. DID YOU KNOW? These events can be so energetic that they have the potential to impact Earth's space environment. This Is Interesting For A Few Reasons If a CME were to hit earth directly, it could disrupt communication systems, interfere with satellites, and even create beautiful auroras at high altitudes. What's even more intriguing is the sheer scale of these ejections. The mass of a typical CME is enormous often exceeding that of several Mount Everests combined! This showcases the dynamic and powerful nature of our sun whose activity can have far reaching effects in our solar system. NOW YOU KNOW!

## Questions & answers

**Q: Where do CMEs come from?**  
A: The Sun's outer atmosphere. _(Source: Write-up · Exhibit A (From the corona) · NOAA SWPC: Coronal Mass Ejections; Wikipedia: Coronal mass ejection)_

**Q: How much material can a CME eject?**  
A: Per NOAA's SWPC. _(Source: Write-up · Exhibit B (Billions of tons) · NOAA SWPC: Coronal Mass Ejections)_

**Q: Why are CME mass estimates lower limits?**  
A: Part of the cloud goes unmeasured. _(Source: Write-up · Exhibit C (Average mass) · Wikipedia: Coronal mass ejection)_

**Q: What can an Earth-directed CME cause?**  
A: It disturbs Earth's magnetic field. _(Source: Write-up · Exhibit D (Geomagnetic storms) · NOAA SWPC: Coronal Mass Ejections; Wikipedia: Coronal mass ejection)_

**Q: What happens to auroras during big storms?**  
A: They can be seen farther from the poles. _(Source: Write-up · Exhibit E (Auroras) · NOAA SWPC: Coronal Mass Ejections; Wikipedia: Coronal mass ejection)_

## Sources

- [NOAA SWPC: Coronal Mass Ejections](https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections)
- [Wikipedia: Coronal mass ejection](https://en.wikipedia.org/wiki/Coronal_mass_ejection)

## Cite this case file

Easterling, Marcus. "Coronal Mass Ejection." The Detail Department (DetailEnjoyer), case file DD-091, last updated Nov 24, 2023. https://detailenjoyer.com/case/coronal-mass-ejection/