Facts about the Aurora Australis
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Oxygen atoms at 557.7 nanometers wavelength produce the Aurora Australis's distinctive green color, the same emission line that makes neon signs glow.
- 09
Ultraviolet emissions from the Aurora Australis are invisible to human eyes but measurable by satellites, revealing a much more intense display than what ground observers perceive.
- 08
The Aurora Australis typically spans 3 to 6 degrees of latitude and can extend across 1,000 kilometers or more in longitude during moderate geomagnetic activity.
- 07
Maximum brightness of the Aurora Australis occurs during the solar maximum phase of the 11-year solar cycle, when sunspot activity peaks and increases geomagnetic disturbance frequency.
- 06
Southern Australia's Aboriginal peoples observed and documented the Aurora Australis in oral traditions and artwork dating back thousands of years before European contact.
- 05
Electrons and protons from the solar wind collide with atmospheric gases to create the Aurora Australis, a process requiring charged particles traveling at speeds exceeding 45,000 kilometers per hour.
- 04
Geomagnetic storms rated 8 or 9 on the 0-9 Kp index can push Aurora Australis displays as far north as Brisbane, over 2,000 kilometers from the Antarctic Circle.
- 03
During severe geomagnetic storms, the Aurora Australis can be visible from Tasmania and southern Victoria, locations roughly 3,000 kilometers north of Antarctica.
- 02
In 1770, Captain James Cook observed the Aurora Australis from the east coast of Australia, marking one of the earliest European documented sightings.
- 01
Altitudes between 100 and 300 kilometers produce the Aurora Australis's characteristic green and red light emissions through oxygen excitation.