|
Credit & Copyright: Frank Andreassen (nettfoto.no)
Explanation:
What causes gaps between aurora curtains?
These unusual gaps can make
Research using data from four
Cluster spacecraft orbiting the Earth has likely found the secret:
auroral gaps, sometimes knows as black auroras, are actually anti-auroras.
In normal auroras,
electrons and/or predominantly negatively charged
particles fall toward Earth along surfaces of constant
magnetic field.
They ionize the
Earth's atmosphere on impact, causing the bright glows.
In auroral gaps, however, negatively charged particles may be sucked out
from the Earth's
ionosphere
along adjoining
magnetic field lines.
These
dark anti-auroras can climb to over 20,000 kilometers
and last for several minutes.
Pictured above, a series of well-defined
auroral gaps is seen dividing green aurora curtains high above
Harstad,
Norway, earlier this month.
News: Solar Eclipse Today
|
January February March April May June July August September October November December |
| ||||||||||||||||||||||||||||||||||||||||||||||||
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: aurora - black aurora
Publications with words: aurora - black aurora
See also:
- APOD: 2024 January 14 Á Dragon Aurora over Iceland
- APOD: 2024 January 3 Á A SAR Arc from New Zealand
- APOD: 2023 December 12 Á Aurora and Milky Way over Norway
- The SAR and the Milky Way
- APOD: 2023 November 5 Á Creature Aurora Over Norway
- APOD: 2023 October 22 Á Ghost Aurora over Canada
- APOD: 2023 April 19 Á Auroral Storm over Lapland