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Eclipse-Mania!

The October 8, 2014 total lunar eclipse.

The October 8, 2014 total lunar eclipse.

By Jim Haklar

I love eclipses. I mean, I really love eclipses! I love eclipses so much that two years ago, I flew to Albuquerque for the weekend to see a solar eclipse. But more about that later…

An eclipse happens when the Earth, Moon and Sun all line up. Technically, this is called syzygy (try to form that word in a game of Scrabble). A lunar eclipse happens when the earth is between the Moon and the Sun. When the Moon is between the Sun and the Earth you get a solar eclipse. Lunar eclipses happen when the Moon is full and solar eclipses occur when the Moon is new. So, why don’t we have an eclipse twice a month? Well, the Moon’s orbit is tilted by a little over five degrees. So most of the time there isn’t perfect alignment and you don’t have syzygy.

From any given location on the Earth, lunar eclipses are more frequently seen than solar eclipses. That’s because the Earth casts a bigger shadow on the Moon than the Moon does on the Earth. The shadows consist of two parts. There is a smaller, darker umbra surrounded by the lighter penumbra. If you are in a location where the Moon’s umbra passes through, you will see a total solar eclipse. Otherwise the solar eclipse will be partial (since you will be in the penumbra). For lunar eclipses, the situation is a little different. The Moon can completely or partially pass through the Earth’s umbra (resulting in a total or partial lunar eclipse) or just pass though the penumbra (called a penumbral eclipse).

Now for my Albuquerque story. Two years ago the Moon’s umbra passed directly in front of the Sun and this was visible in many cities including Albuquerque (I went to Albuquerque because of the clear weather). But since the Moon was at a point in its orbit when it was farther away from the Earth, it didn’t completely block out the Sun. Instead, an annulus or ring of light from the Sun’s disk encircled the Moon. This is called an annular solar eclipse.

On August 21, 2017 there will be the first a total solar eclipse visible from the contiguous United States in over 30 years. Information on the best places to see the eclipse is already on the Web, so start think about taking an eclipse vacation!

About the Author: Jim is an environmental engineer at the EPA’s Edison, New Jersey Environmental Center. In his 28 years with the agency he has worked in a variety of programs including Superfund, Water Management, Public Affairs, and Toxic Substances. He has been an amateur astronomer since he was a teenager, and can often be found after work in the back of the Edison facility with his telescope.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

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Light Pollution and Amateur Astronomy

This picture of the Sun was taken on September 26, 2014 from the Edison Environmental Center.

This picture of the Sun was taken on September 26, 2014 from the Edison Environmental Center.

By Jim Haklar

One of my hobbies is astronomy, and for me there is nothing more relaxing than looking up at a sky full of stars. However, light pollution has made it increasingly difficult for people to enjoy the wonders of the night sky. Light pollution represents energy that’s being wasted. Think of an older style “bulb” type streetlamp (where the bulb hangs upside-down from a pole). A portion of the light coming from the bulb lights the street below, but some of the light travels upward and contributes to the nighttime glow. While there are communities that require the use of special “directed” lighting, we have a long way to go before we’ll be able to see the Milky Way from lower Manhattan.

Amateur astronomers have several options for dealing with light pollution. They can use special filters that block the wavelengths of light emitted by nighttime lighting. However, those filters also block some of the light emitted by stars or galaxies and that can be a problem when viewing or taking photos of these objects.

Another option is to drive to a location where the light pollution is minimal. For someone living in the New York City area, this may mean driving for several hours. You also have to consider whether the location you’re observing from is safe. There have been times when I’ve been startled by a nocturnal animal who wandered too close to my equipment. While I don’t mind a deer joining me for an evening of observing, I definitely would have problems spending my quality time with a skunk!

One other alternative is solar astronomy. By using a properly filtered telescope to look at the Sun during the day, light pollution is never an issue. And the Sun’s surface changes from day to day. I can also get to bed at a reasonable hour (and avoid my smelly nighttime companions).

In spite of the light pollution I still believe that astronomy is a worthwhile hobby. No matter where you live, be it the city, suburbs or a rural area, there will always be something to see in the sky. Just look up.

About the Author: Jim is an environmental engineer at EPA’s Edison, New Jersey Environmental Center. In his nearly 30 years with the Agency he has worked in a variety of programs including Superfund, Water Management, Public Affairs, and Toxic Substances. He has been an amateur astronomer since he was a teenager, and can often be found after work in the back of the Edison facility with his telescope.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.

The Fun of Solar Imaging

This image of the Sun was taken by the author using a hydrogen alpha filter.

By Jim Haklar

A lot has been written about the benefits of solar power as a “green” source of energy.  But have you ever wondered what that source of energy actually looks like?  While we can’t look directly at the Sun without protection for our eyes, we can use special equipment to see the Sun in all its glory.

Astrophotography is one of my hobbies, and often on a clear day I’ll take my telescope and camera out at lunchtime and take pictures of the Sun.  I have special filters that allow me to see the different types of light that the Sun gives off.  One type of light is called “hydrogen alpha,” and with my hydrogen alpha filter the Sun really looks alive!  Just like all of us, the Sun goes through periods when it is more active and less active.  For the Sun, these periods come in 11- year cycles and scientists are predicting that in the current cycle the Sun will be most active next year.  But even now many solar features can be seen.

Loops of gas called prominences are present at the edge of the Sun; when prominences cross over the face of the Sun they look like ribbons and are called filaments.  Sometimes huge surface explosions called solar flares can also be seen, as well as sunspots.  The Sun is so big (over 800,000 miles across) that all of the features I’ve described are usually larger than the Earth.  Talk about solar power!

About the Author: Jim is an Environmental Engineer out of EPA’s Edison, New Jersey facility, where he manages PCB cleanups.  Over the last 27 years he has worked in a number of different programs within EPA, including Superfund, water management, and public affairs.   He has been an avid amateur astronomer for over 30 years.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.