File:Earth's x-ray aurora borealis 2004 composite.jpg
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Summary
| Description |
English: A team of scientists observed Earth’s north polar region ten times during a four-month period in 2004. As the bright arcs in this sample of images show, they discovered low-energy (0.1 - 10 kilo electron volts) X-rays generated during auroral activity. Other satellite observatories had previously detected high-energy X-rays from Earth’s auroras.
The images – seen here superimposed on a simulated image of the Earth – are from approximately 20-minute scans during which Chandra was pointed at a fixed point in the sky while the Earth’s motion carried the auroral region through the field of view. The color code of the X-ray arcs represents the brightness of the X-rays, with maximum brightness shown in red. Auroras are produced by solar storms that eject clouds of energetic charged particles. These particles are deflected when they encounter the Earth’s magnetic field, but in the process large electric voltages are created. Electrons trapped in the Earth’s magnetic field are accelerated by these voltages and spiral along the magnetic field into the polar regions. There they collide with atoms high in the atmosphere and emit X-rays (see the accompanying illustration). |
| Date | (2004-01-24, 2004-01-30, 2004-02-15, 2004-04-13) |
| Source | CHANDRA X-ray Observatory CXC Operated for NASA by SAO, url=http://chandra.harvard.edu/photo/2005/earth/ |
| Author | NASA/MSFC/CXC/A.Bhardwaj & R.Elsner, et al.; Earth model: NASA/GSFC/L.Perkins & G.Shirah |
| Permission (Reusing this file) |
Images from NASA usually are free of copyright. |
Distance from the North pole to the black circle is 3,340 km (2,075 miles). Observation dates: 10 pointings between 16 December 2003 - 13 April 2004. Instrument: HRC. Ref: Anil Bhardwaj et al. 2005, Journal of Atmospheric and Solar-Terrestrial Physics (in press).
Licensing
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This file is in the public domain in the United States because it was solely created by NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (See Template:PD-USGov, NASA copyright policy page or JPL Image Use Policy.) |  |
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File history
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 21:36, 3 March 2014 | 3,300 × 2,550 (1.88 MB) | Scanmap | hell yeah | |
| 21:12, 3 March 2014 | 792 × 612 (504 KB) | Scanmap | greater resolution | ||
| 00:08, 25 November 2009 | 420 × 325 (104 KB) | Marshallsumter | {{Information |Description={{en|1=A team of scientists observed Earth’s north polar region ten times during a four-month period in 2004. As the bright arcs in this sample of images show, they discovered low-energy (0.1 - 10 kilo electron volts) X-rays |
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- Usage on beta.wikiversity.org
- Radiation astronomy/X-rays
- Usage on en.wikiversity.org
- User:Marshallsumter/Radiation astronomy2/X-rays
- Plasmas/Plasma objects/Coronal clouds
- Stars/X-ray classification
- User:Marshallsumter/Radiation astronomy/Electrons
- User:Marshallsumter/Radiation astronomy/Beta particles
- Plasmas/Plasma objects/Auroras
- Gases/Gaseous objects/Earth
- Usage on fr.wikipedia.org
- Source astrophysique de rayons X