I Can See The Light!
2017-10-03 16:47:53.000 – Ryan Knapp, Weather Observer/Staff Meteorologist
As the
About Us page on our website states, “Mount Washington Observatory is a private, nonprofit, member-supported institution with a mission to advance understanding of the natural systems that create Earth’s weather and climate. It serves this mission by maintaining a weather station on the summit of Mount Washington, performing weather and climate research, conducting innovative science education programs, and interpreting the heritage of the Mount Washington region.” And as a meteorologist (the study of weather), the Observatory is a great place to experience Earth’s weather first hand. However, being the night Observer up here for over a decade, the night sky is a nice little side hobby I have learned to enjoy.
Now, I will be the first to admit that I barely know constellations or exactly what I am looking at on any given night. If someone were to ask me what such-and-such thing is in a direction of the sky, I would flat out not have a clue most of the time. But if I have my cellphone, my
Sky Map app is a great place to start as it provides augmented reality and displays the name of stars, planets, and constellations. Where that app might fall short though, I can look up the rest of my inquiries online and usually find the answers with a bit of research. I also subscribe to several great newsletters and review a few webpages for pointers about what I am looking at, or what I should look for over the course of a night, a week, or a month’s time. My three favorite sites that I frequent are
earthsky.org,
skyandtelescope.com, and
space.com.
Last month I received a reminder to keep an eye out for the Zodiacal Light. The Zodiacal Light occurs twice a year; for the northern hemisphere is it seen after dusk in the spring and before dawn in the autumn. Since it is autumn, this means it is visible during astronomical dawn and a bit into nautical dawn or in simpler terms, 90 to 180 minutes prior to sunrise. It appears as a hazy pyramid of dim light in the eastern skies and for NH and New England, it will tilt southward (at the equator it shoots straight up and in the southern hemisphere is leans north). In a quick summary, it is formed by sunlight reflecting off space dust the size of 1-300 micron (or 0.001-0.3 mm) in a plane spanning between Mercury and Jupiter. (If you want to learn more, head
HERE,
HERE, or
HERE)
Over the past month, I kept seeing it during the last few weather observations of my night shift but weather (clouds and winds) always kept me from getting a good picture of it. Then on one night last shift, we had a complete undercast (blocking city lights below), completely clear skies overhead, relative humidity in the teens, no moonlight, and calm winds making for a great opportunity to get out and photograph the Zodiacal Light. So I took 15 minutes and wandered around the summit photographing it from a few different spots (see results below). During most years, I typically get to see it a handful of nights in Sept/Oct before it is gone. This year though, New England has had a couple strong high pressure ridges over the past couple of weeks allowing for generally clear skies resulting in additional viewings both at work and around where I live down below when off-summit.
If you want to view it, here are a few pointers: First, it needs to be clear skies to the east. A few high clouds are OK, but the clearer your skies, the better. Second, make sure there is little to no moonlight (hard to do now as the moon is nearly full; but it will be waning soon enough. Third, get away from any and all light pollution – the darker the skies around you the better. Fourth, go someplace with good views to the east – a rise in land, a cliff, a hill/mountain top (it doesn’t need to be Mt Washington, just one good with great extended views east), a lake/pond, or the ocean. If going near a body of water or someplace where fog can form, be mindful that this could dim or block things. Fifth, allow your eyes time to adjust. That typically means 5 to 20+ minutes of not looking at any light – that includes your cell phone! The longer you allow your eyes to adjust, the easier it will be to view the night sky. Even then though, for most people, “averted vision” or “peripheral vision” works best to see it. This means you look slightly left or right of due east to see the glow at its best as the eye’s rod detectors away from our central vision are more sensitive and can pick up on this dim light.
Lastly, since it is fall, dress in a couple warm layers as the mornings have been getting down in the 30s for most areas. And that is about it. You can watch it grow taller and brighter over time prior to eventually giving way to the blue of dawn and then sunrise. If photographing it, you will need a tripod or sturdy surface, a wide-angle lens, a large aperture, increased ISO, and and extended exposure done by either a shutter timer or remote (if you need additional pointers, one of the articles I linked to above has additional information for photographing it). I hope this helps and that you get a chance to see if for yourself. If you miss it this go around though, don’t fret as it’ll be back in spring after dusk.
Zodiacal Light with the Mount Washington Observatory instrument tower and NHSP Sherman Adams Building
Zodiacal Light and a coin-operated viewing scope
Zodiacal Light with stratus clouds and the Carter-Moriah-Wildcat Range
Zodiacal Light over the Mt Washington Auto Road
Ryan Knapp, Weather Observer/Staff Meteorologist