Trigger Amazing Light Shows.
Somewhere in the middle of
a cold Alaska winter night while the Aurora displays it's brilliant light,
you might find Jan Curtis and his camera capturing images of the beautiful
The Aurora Borealis, otherwise
known as the Northern Lights, are most predominate north of the Arctic
Circle. But, on occasion, they can be seen as far south as Cuba and maybe
even further south than that, according to Curtis.
|Curtis, a retired naval
officer, now works as a Climate researcher for the University of Alaska
in Fairbanks. He has all his film developed by Kodak and figures he has
taken as many as 1,500 photos of the Northern Lights in the last 5 years.
His images are so popular in fact, they have been used in many publications
and illustrations. The photo above, was presented to the Prime Minister
of Japan in May of 1999 and featured in NASA's APOD.
What Causes The Aurora?
When the sun has what's known
as a coronal mass ejection, otherwise known as a solar flare, it sends
solar wind containing protons and electrons into space. If earth happens
to be in the path of these solar winds when they pass by, the elements
strike the magnetosphere, the area above earths magnetic poles, and generate
a virtual magnetic and Auroral storm.
When components of the upper
atmosphere such as nitrogen and oxygen are bombarded by the solar wind,
they become excited, generating different colors. The predominant color
is green, Curtis explains. But reds and blues are also possible depending
on the type of molecules the solar wind is interacting with. Much the same
as the colors you see in a neon light, he added.
When Can They Be Seen?
During a recent interview
with Curtis, he said, "There's a long term cycle, which is known as the
11 year sun spot cycle, which we are actually at the solar maximum point
as we speak. For the next several years there will be more opportunities
for the Aurora to occur."
The best time for seeing
the Aurora according to Curtis, is during the winter and early spring.
Mainly because these seasons produces some of the clearest skies. If you
were living in a big city, the chances are you would never even know they
were there due to the city light or pollution. However, the further north
you go, the better your chances will be to observe them, mainly because
they are more frequent.
During the winter in Alaska,
Curtis explains, the sun doesn't rise north of the Arctic circle. At that
point, the Aurora would be best for viewing in the northern hemisphere.
In the northern hemisphere you have the northern lights, otherwise known
as the Aurora Borealis. In the southern hemisphere you have the southern
lights, known as the Aurora Australis. However, when you consider there
isn't any land within several hundred miles of the Antarctic, the northern
lights are your best bet and Alaska is your best choice. Unless of course
you were in space.
NASA's SOHO spacecraft, or
Solar and Heliospheric Observatory, follows events such as eruptions on
the sun in real time. The reason being, large Auroral events can trigger
disruptions in communications and even power outages.
The speed of the solar wind
is determined by the size of the solar flare, but speeds of 2 million miles
per hour are average. That offers some form of early warning, but NASA's
ACE spacecraft, short for Advanced Composition Explorer which sits 1.6
million miles closer to the sun, gives us 45 minutes of warning time. It
also gives a more accurate account of what size of event can be expected.
That provides crucial lead time for power companies to "power down," before
power grids are overloaded.
NASA photo of the Aurora
|A large Auroral storm in
September of 1971 generated power grid problems, and transformers in British
Columbia even exploded. During a solar maximum event in 1989, a power grid
in Quebec blew out, putting six million people without power for nine hours.
So monitoring solar flares and predicting Auroral events are vital to our
welfare where power and communications are concerned.
Although the Aurora never
comes closer than about 60 miles from earth's surface, it can extend as
high as 300 miles. Curtis explains the static electricity from such events
generate other problems as well.
Hearing The Aurora
Some have claimed they can
actually hear it. However, Curtis explains, that's impossible due to the
altitude at which they occur. Since they are happening in space, they are
occurring inside a vacuum. And if there's no atmosphere for sound to propagate
from, you can't hear anything.
However, Curtis said, "Alaska
is famous for the Alaskan Pipeline that travels 600 miles from the north
part of Alaska through the gulf of Alaska 600 miles to the south, and they
actually have to insulate the pipeline against static discharge. It's quite
an amazing thing. It's almost like an electrical storm. (a thunderstorm).
The static can build up to tremendous amounts, so what people are hearing,
especially in the most intense displays, are probably that phenomenon."
Curtis said the Aurora is
monitored around the world all the time. National Public Radio used specialized
equipment aimed at the Aurora and has captured sounds coming from it. The
results were remarkable to say the least. What was captured was a series
of swishes, choruses and crackling noises.
Some early researchers, who
claimed to have heard them, discovered that when their eyes were covered
they couldn't hear them, but when they were looking at it, they could.
A possible explanation: the light interacting with nerves in the eyes, sending impulses
to the brain, thus creating sound within the observer's head.
that predictions of such events can't be predicted by more than a few days
in advance. But, Curtis explains, predicting Auroral storms is actually
better than predicting the weather. "The key to actually seeing them is
Thanks to ACE, the exact
time and magnitude of displays are narrowing that down.
Curtis explains that if you
miss an Auroral event, don't be discouraged. The sun rotates on it's axis
and takes 28 days until it faces the earth again. So if you missed this
one, about 4 weeks from now you stand a good chance of seeing it.
In the land of the midnight
sun, Alaskan temperatures can easily dip to a chilly
-40 to -60 below zero. When
taking pictures of the Northern Lights Curtis explains, it's not always
that extreme, but you can expect temperatures near or slightly below zero.
However, Curtis offers these words of advice. "A good goose down parka,
insulated boots and warm gloves should keep you warm enough."
Northern Lights don't happen all that frequently in shallow latitudes,
they do on occasion make an appearance.
"They're a phenomenon that
once you see, you want to see over and over again because they are very
beautiful. But as I emphasized before, the key to actually being successful
in seeing them is patience. Sometimes it's really cold outside and you
don't want to be there, but when the displays start up, you forget about
the cold and really enjoy what you're observing," Curtis said.
Considering most people never
see the Aurora and the solar maximum condition now, a trip to Alaska, or
keeping an eye on solar activity, could provide those with patience the
opportunity of a lifetime.
The man behind the images,
Jan Curtis, climate researcher for the
University of Alaska Geophysical Institute, Fairbanks,
- Hear Jan Curtis in his own words.
Public Radio report - Hear the sounds of the Aurora.
- Jan Curtis' fantastic collection of Aurora images.
of the Aurora.
Division of Tourism - Important traveler information
forecast - Shows current expected location of Aurora Borealis.
- Real time images of the sun. Includes SOHO real time screen saver link.
- Real time Aurora images from space covering the north and south poles.
APOD - Astronomy Picture Of the Day (Current and Archive).