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Seeing the
northern lights is regarded by many as an experience that happens
once, maybe twice in a lifetime. With a lot of knowledge, and a
some luck, you can take once in a lifetime odds and make them
more like several times per year. This section
of this website aims to give you the facts and keep you alerted
to times when the northern lights may become visible.
Shortly
after a couple of photo galleries featuring the Northern Lights
in the Lakes Region were posted to this site, my inbox began to
light up. I began receiving  dozens and dozens of emails from
people asking when they could see the northern lights, how I
knew to look when I did, and so on. Based upon the
response, I've decided to spill what I know and assist others in
the skills of middle latitude aurora hunting.
So are you ready to dive into
aurora hunting? Before the creation of this page, aurora
hunting was a hobby
most people wouldn't have had the will and persistence to endure. If
you wanted to see the aurora,
then you were going to miss sleep, you were going to freeze your
fingers off, and you would need to adapt to long nights spent waiting in
the dark. Moments after you've given up and gone home with
frustration, the light show will erupt and when you check this
page the next day, you'll see the photos I took from the same
spot you were standing. Stalking the aurora used to be the ultimate game of
patience.
That was then.
Now, you can sign up for email notification and I'll email you
whenever the chances look good enough. Just click here and
enter your email address. If things look promising, I'll
send out an email whenever conditions warrant, and occasionally
up to 12 hours in advance. I've gotten this down to a science,
so I know with pretty amazing accuracy when and how good things
will get.
One question I get
a lot is is how often can I see the northern lights? Well, there is no real
answer, it depends on the level of activity on the sun. Overall,
an opportunity to view the northern lights here presents itself
far more often than one would think. On average,
you could see the northern lights here once or occasionally
twice a month during active periods of solar activity, and once
every one to three months during quieter periods. 
So now, if auroras
happen so frequently, why haven't you ever seen them before? It
doesn't matter how long you've lived here or how many nights
you've spent sleeping under the stars, your story is the same as 99.9
or the general population. There is an absolutely huge list of
things all working in conjunction to prevent you from seeing
anything. What follows is the much abridged list.
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First off, if
you're spending a lot time outside at night, it's most
likely in the summer. Summer nights are very short and often very hazy. Lights from
even the smallest of towns illuminates the haze, and so the
sky is never really as crisp and clear as it is in January.
This impairs visibility.
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In the winter,
it's often cloudy or foggy and usually too cold to spend an
extended amount of time looking.
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Peak viewing
times are often between 11pm and 3am. How many people care
enough to sacrifice sleep?
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Clouds often
hide 3/4 of the displays.
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The moon is
enough to dampen any minor display down to unnoticeable
levels, but the moon has little impact on a strong display.
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Displays can
last only a few minutes. You could wake up every 15
minutes and look outside, and still miss it.
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Auroras at
this latitude frequently occur low on the horizon, and due
to hills and mountains, an unobstructed view of the horizon
is seldom available from your bedroom window.
There are just of
few of the things that are working against you, and knowing what
stands in your way is the first step toward successfully viewing
an aurora. Chances are, you have been outside when a display of
the lights was going on, you might even have looked up at the
sky. Unfortunately, it was probably cloudy, or you kept
your eyes on the ground as you navigated an ice covered driveway
to get to your car. Maybe you saw something that seemed unusual
but you just attributed it to city lights.
Now suppose you do
see the northern lights. If you browse a lot of aurora
photos online, more often than not, you're likely to be disappointed
once you see the lights in person. Cameras can be set to take photos with lengthy exposure times,
thus making even the faintest of lights appear off the charts
spectacular. I take special care to ensure photos you see
on this site  accurately represent what was seen in the skies. In New Hampshire, most displays of the Northern
Lights will be confined to the northern sky, usually about 15-50
degrees above the horizon. Colors of red, orange, blue,
violet and purple are rare to the eyes, but not on film.
Those colors are there, but you need either an extraordinarily
dark location (The northern tip of New Hampshire is as close to
a true dark sky site as you can get without driving more than 8
hours.) to see them, or a camera which can reveal what your eyes
can not. To your eyes, the New Hampshire aurora will be
mostly green, white, and maybe a faint hint of visible
red. Every now and then, a display with bright stunning
reds will occur, such as on 10-30-03, but these shows are comparatively
rare. Overall, the display might be really dull and boring,
or it might be very bright with plenty of visible motion and
even spectacular jaw dropping rapid pulsations.
So you're ready to
see the show in person, and you want to know when to look. If
you haven't signed up for my email alerts, you can take a shot
at deciding for yourself whether you want to go for a drive to a
dark spot or not. First,
click
here to load a real time graph that updates every minute.
When using the data on this chart, it's important to remember
that the data is collected from almost a million miles out in
space, therefore there is a 25-55 minute lag time before the
plotted solar conditions impact the earth. Even once those
plotted conditions impact the earth, the results are not always
instant. It can still take one to three hours for an enhancement
in the northern lights to develop, as the earth needs to
"'charge" up. Getting on to the data, there are five
plots on that graph.
The first plot
contains a red line, known as the Bz." You want to
see that red plot drop below the dashed line to a value of -10,
or lower, and stay that way for more than an hour. This is
the most important piece of information, if the red line is
above the dashed line, in positive territory, the chances of aurous
are almost non-existent. The third plot on
the chart is the density, represented with an orange line.
Here, higher is better. Look for values greater than 10. The fourth plot is
the solar wind speed, represented with a yellow line. Again,
higher is better. Dim northern lights can occur with values as
low as 450, but 525 is usually when things get more
interesting. The October 30, 2003 storm brought solar
winds values of over 1000 km/s.
You can use the
above information alone to come up with a reasonably accurate
forecast of activity, but how can you tell if stuff is actually
happening? First, click
here to view a summary of magnetometers. The second
plot from the bottom on that page is the magnetometer for Ottawa
in Canada. If that line is straight, nothing is happening.
If it's full of squiggles and zig zags, there is action in the skies.
The bigger and more pronounced the zig zags are, the more
intense the activity. Because the northern lights occur so
high in the sky, lights that appear over your head can be seen
as far away as 175 to 300 miles, so you don't need to be right
near a magnetometer for it to be useful for you.
So now you can
tell if a light shows could develop and whether or not they are
happening now. What about seeing if you've missed some, or
for how long they have been going on? Just click
here to load a graph showing the planetary K index. This
chart shows the activity level average over the past three
hours. A value of 5 is for minor displays, which may not be
readily visible. Six is for a moderate display, severe for
a strong display. A seven should provide plainly visible
features such as arcs, rays, and maybe some different colors
such as red. Once that chart reaches 8 or 9, a severe storm has
been underway, and you probably just missed an incredible show.
The October 30, 2003 storm had a K index of 9. It should also be
noted that this figure is a plant-wide average, so northern
lights may not be visible every time this image implies they
should have been.
Next question I
get a lot is how do you photograph them? First you must have a
tripod and the ability to take exposures ranging from 8-20
seconds, depending on the aperture. Exposures longer than 20
seconds may cause star trails, and could also make to aurora
look overexposed. I use a digital camera, since the ability to
check your photos instantly makes getting the proper exposure,
focus, and white balance easy.
Well there you
have it. Spotting an aurora may seen like a lot of work,
and perhaps a little complicated, but when the rewards come,
trust me, it's worth being a little groggy the next day.
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