Edwin L. Aguirre
On Monday, Aug. 21, a total eclipse of the sun
will be visible in the United States
along a narrow track that stretches from Salem, Ore., to Charleston, S.C. People along that path will be able to see the moon completely block the sun for up to 2½ minutes, turning day briefly into night. The rest of North America, Central America and northern South America will be treated to a partial eclipse.
This will be the first time in nearly 100 years that a total solar eclipse will be visible from coast to coast across the U.S. The sun, the moon and the U.S. mainland have to be perfectly aligned for this rare event to occur. Most of the time, the eclipse track either traverses only a portion of the country or misses it altogether.
An estimated 12.2 million Americans, or 3.8 percent of the nation’s population, already live inside the path of the August total eclipse, and tens of millions more reside within a couple of hours’ drive of the eclipse track, making the upcoming event likely to be the most widely watched – and photographed – total solar eclipse in history.
A team of UMass Lowell faculty and staff will be traveling across the country to observe the total eclipse, conduct scientific experiments to study the effect of the moon’s shadow passing over Earth’s upper atmosphere and take photos. They will be spread out at sites across Oregon, Idaho, Wyoming and Illinois to maximize the chances of clear skies on eclipse day.
What Eclipse Watchers in Lowell Can Expect
People will be able to watch the partial eclipse unfold from practically anywhere, provided they have a clear, unobstructed view of the sun. Thin clouds or haze should not pose a problem, but thick clouds may completely obscure the view.
As seen from the UMass Lowell campus, the partial eclipse will begin at 1:28 p.m., when the moon’s edge starts to encroach on the sun’s disk. Maximum eclipse occurs at 2:46 p.m., when the moon will cover 63 percent of the sun, turning it into a thick crescent. The sun will be 50 degrees high in the sky at the time. The eclipse will end at 3:59 p.m.
Throughout the partial eclipse, the sun’s brightness will not diminish in intensity. It will remain blindingly bright, so viewers should take the necessary precautions to avoid damaging their eyes. These precautions should always be followed, regardless of whether there is a partial eclipse going on or it’s just a regular sunny day.
Tips on Observing and Photographing the Partial Eclipse Safely
There are some important things to keep in mind when trying to view a partial solar eclipse.
First, never look directly at the sun without proper eye protection, such as solar viewing glasses
or a solar filter for your camera, binoculars or telescope. Failure to do so can result in serious eye injury or permanent blindness. A No. 14 arc-welder’s glass filter is also acceptable, but ordinary sunglasses and polarizing or neutral-density filters used in regular photography are not safe and should not be used.
You can purchase inexpensive but safe solar viewing glasses, or “eclipse shades,” from companies such as American Paper Optics
, Rainbow Symphony
and Thousand Oaks Optical
. The glasses will not only help cut down the brightness of the sun, but also block out the sun’s harmful ultraviolet and infrared radiation.
An alternative method for safe viewing would be to use the indirect technique – that is, making a pinhole on a piece of cardboard and holding the cardboard up to the sun, without looking at it. You can then project the image of the sun onto a shaded white sheet of paper. The projected solar image would be tiny, dim and fuzzy, but it’s perfectly safe to look at.
You can also look under leafy trees
; the tiny spaces between the leaves act as natural pinholes, projecting dozens of small solar crescents on the shaded ground. Lay down a white blanket to see the crescents better.
If you want a brighter, sharper solar image, use an unfiltered telescope (or one side of your binoculars) to project a magnified image of the sun’s disk onto a sheet of paper. The projected image can be safely viewed and photographed. Be sure to cover the telescope’s finder scope and the unused half of the binoculars, and do not let anyone look through them.
If you would like to shoot the partial eclipse through a telescope or telephoto lens, be sure to securely mount a safe solar filter in front of your optics
. You can order the correct size of filter from dealers such as Meade
and Orion Telescopes & Binoculars
You can use your point-and-shoot camera or your smartphone to take decent pictures of the partially eclipsed sun, but you have to shoot them through a properly filtered telescope. If you just hold up your pocket camera or smartphone to the sun and try taking snapshots, you won’t be able to record anything because all your photos will be completely overexposed.
To shoot through a properly filtered telescope, you must first insert a low-power eyepiece into the focuser and focus the telescope on the sun. Hold your camera or smartphone and aim its lens directly into the eyepiece. Use the LCD screen to center the sun, and zoom in as needed. You can use the camera’s autofocus and auto-exposure settings and try to hold the camera as steady as you can while clicking the shutter button.
If you want to use a full-size digital SLR camera, you should attach your camera body securely to the telescope focuser using an appropriate adapter for your camera brand (check with your local camera retailer). To minimize vibrations, use an electronic cable release to operate the shutter.