Coloring an Aurora The colors of the aurora vary, depending on altitude and the kind of atoms involved. If ions strike oxygen atoms high in the atmosphere, the interaction produces a red glow. This is an unusual aurora—the most familiar display, a green-yellow hue, occurs as ions strike oxygen at lower altitudes.
Reddish and bluish light that often appears in the lower fringes of auroras is produced by ions striking atoms of nitrogen. Ions striking hydrogen and helium atoms can produce blue and purple auroras, although our eyes can rarely detect this part of the electromagnetic spectrum. To find out more about the mysterious light displays, scientists have launched satellites specially designed to study auroras.
Fox Fire In Finland, the aurora borealis is called revontulet , which literally translates to fox fires. According to one Finnish folk tale, the lights are caused by a magical fox sweeping his tail across the snow and sending sparks up into the sky. Dawn Wind The aurora borealis , or northern lights, was studied by ancient Roman and Greek astronomers. The phenomenon was named for the Roman goddess of the dawn, Aurora, and the Greek god of the north wind, Boreas. Also called the southern lights.
Also called the northern lights. Gas molecules are in constant, random motion. Also called a temperate zone. National Aeronautics and Space Administration the U. The bright bands of color around the North Pole caused by the solar wind and the Earth's magnetic field. RAdio Detection And Ranging method of determining the presence and location of an object using radio waves. Also known as the aurora australis. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
The Rights Holder for media is the person or group credited. Caryl-Sue, National Geographic Society. Dunn, Margery G. Read our Northern Lights FAQ and learn how you can increase your chances of catching a glimpse of this awe-inspiring light show in the sky. Get unique insight and knowledge about the Arctic sky and the greatest lightshow on Earth, the Aurora Borealis, on the popular Astronomy Voyage along the mesmerising Norwegian Coast. This limited voyage is accompanied by special lecturers - experts on astronomy and expeditions to see the Northern Lights.
Read more about our Astronomy Voyage. Covid Updated information. Hurtigruten Group Go to Hurtigruten Expeditions. Go to Norwegian Coastal Express. What causes the Northern Lights? What's the story behind the Northern Lights? An auroral display might be observed any night from dusk until dawn as long as it is dark, which excludes Alaskan summer nights May-July. The best time to view them is between midnight and 2 am. What are the Northern Lights?
Blown towards the earth by the solar wind, the charged particles are largely deflected by the earth's magnetic field. However, the earth's magnetic field is weaker at either pole and therefore some particles enter the earth's atmosphere and collide with gas particles.
These collisions emit light that we perceive as the dancing lights of the north and the south. The lights of the Aurora generally extend from 80 kilometres 50 miles to as high as kilometres miles above the earth's surface. Northern Lights can be seen in the northern or southern hemisphere, in an irregularly shaped oval centred over each magnetic pole.
The lights are known as 'Aurora borealis' in the north and 'Aurora australis' in the south. Scientists have learned that in most instances northern and southern auroras are mirror-like images that occur at the same time, with similar shapes and colors.
Because the phenomena occurs near the magnetic poles, northern lights have been seen as far south as New Orleans in the western hemisphere, while similar locations in the east never experience the mysterious lights. However the best places to watch the lights in North America are in the northwestern parts of Canada, particularly the Yukon, Nunavut, Northwest Territories and Alaska. Auroral displays can also be seen over the southern tip of Greenland and Iceland, the northern coast of Norway and over the coastal waters north of Siberia.
Southern auroras are not often seen as they are concentrated in a ring around Antarctica and the southern Indian Ocean.
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