Tag Archives: eclipse

NASA Marshall Team Observing and Taking Questions about Upcoming Lunar Eclipse

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In the Americas on Sunday night, Sept. 27, we will be treated to a lunar eclipse with its beautiful orange and red colors, a prelude to the fall color of leaves in Earth’s Northern Hemisphere. This eclipse will straddle midnight on Sept. 27, depending on where you live. If observing close to the Greenwich Meridian in the U.K., the eclipse begins just after midnight, in the morning of Sept. 28 at 00:11 Universal Time (UT). But Sept. 28, 00:11 UT, translates to Sept. 27, 8:11 p.m. EDT and 7:11 p.m. CDT.

All of the Americas are well placed to see this eclipse. The table below lists eclipse timing details. If you have questions about this eclipse, you will have an opportunity to ask experts at NASA’s Marshall Space Flight Center in Huntsville, Alabama!

About Lunar Eclipses

Throughout human culture, lunar eclipses have been viewed with awe and sometimes fear. Today we know that a total lunar eclipse happens when the full moon passes through the darkest part of Earth’s shadow, the umbra. Near the beginning and ending of an eclipse, the moon moves through a less dark portion of the shadow, called the penumbra, which is hardly visible. The partial phase begins (ends) when the moon enters (leaves) the umbra. When the moon has completely passed into Earth’s shadow, the eclipse is in its total phase.

The length of the eclipse is dependent on the position of the moon along an Earth-sun line. The longest eclipses occur when the moon is directly in line with Earth and sun. The shortest eclipses are when the moon is either above or below that line. The moon does not make its own light; it only reflects the light it receives from the sun. During a lunar eclipse, the moon appears less and less bright as sunlight is blocked by Earth. As totality approaches, more and more of the sunlight reaching the moon does so indirectly; it is refracted around the “edges”of Earth, through our atmosphere.

Because the light is going through the Earth’s atmosphere, almost all colors except red are “filtered” out and the eclipsed moon appears reddish or dark brown. The filtering is done by particulates in the atmosphere; when there have been a lot of fires and/or volcanic eruptions, lunar eclipses will be darker and redder. This eerie but harmless effect has earned the tongue-in-cheek nickname “blood moon.”

Supermoon – No, not SuperMan, SuperMoon

The moon orbits Earth in an ellipse that is almost circular (as is the orbit of most planets around the sun), but because the orbit is elliptical, sometimes the moon is closest to Earth (perigee) and sometimes farthest from Earth (apogee). The position of the moon for the Sept. 27/28 eclipse is very close to perigee, so it will appear a bit larger in the sky than a month from now.

You could measure this, with simple items from around the house. Try using a coin (or button or marble) at arm’s length to block the full moon, do this at a particular time, then try it again for the next several months at full moon, at the same time. If the coin (or other item) covers the moon on Sept. 27 (2015), it will more than cover the moon at later times, proving that the moon is smaller and thus farther away. Also, because the moon is at perigee (close approach to Earth) a supermoon will cause slightly larger tidal effects.

How to View and Ask Questions

NASA’s Marshall Space Flight Center will offer a live Ustream view of the lunar eclipse on the Sept. 27, the night of the event, via the Marshall Center Ustream feed. The live feed is an alternative for observers caught with bad weather or light-polluted night skies.

Mitzi Adams, a solar physicist at Marshall, will talk about what viewers are seeing on screen and answering questions from Twitter. To ask a question, use the hashtag: “AskNASA.”


Ask an Astronomer About the Shortest Lunar Eclipse of the Century on April 4

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On Saturday morning, April 4, 2015 not long before sunrise, the bright full moon over North America should turn a lovely shade of celestial red during a total lunar eclipse. Join NASA astronomer Mitzi Adams as she takes questions via Twitter @NASA_Marshall. For Twitter questions, use the hashtag #eclipse2015. The question and answer via Twitter will begin at 6 a.m. EDT and continue through the end of the eclipse (approximately 8:00 a.m. EDT on April 4).

The lunar eclipse will be visible from all parts of the United States.  Eastern North America and western South America can see beginning stages of the partial umbral eclipse low in the west before sunrise April 4, whereas middle Asia (India, western China, mid-Asian Russia) can view the ending stages of the partial umbral eclipse low in the east after sunset April 4. Greenland, Iceland, Europe, Africa and the Middle East won’t see this eclipse at all. A world map of eclipse visibility is available here. The total eclipse will last only five minutes. You can find more information  here.

This image shows the Dec. 20, 2012 total lunar eclipse, as seen from Sagamihara, Japan.

This image shows the Dec. 20, 2012 total lunar eclipse, as seen from Sagamihara, Japan.

Marshall Scientists to Take Questions via Twitter About the Partial Solar Eclipse

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On Thursday, October 23, 2014, from 5:00pm – 6:00pm CDT, Marshall scientists Mitzi Adams, Sabrina Savage and Alphonse Sterling will be taking questions about the partial solar eclipse on the NASA Marshall Twitter account: http://twitter.com/NASA_Marshall, using the hashtag #askNASA.

At approximately 4:54 p.m. CDT, the eclipse will begin, with maximum eclipse occurring at 5:54 p.m. The partial eclipse will end at 6:49 p.m. CDT, which is after 6:02 pm sunset in Huntsville.

The magnitude of this eclipse, that is the fraction of the Sun’s diameter covered by the moon, will be 44%.  The obscuration, or the fraction of the Sun’s area occulted by the moon, will be 32%.The Sun will be in the constellation Virgo, with Saturn low on the horizon after sunset, and Mars will be farther to the east.

A live Ustream feed of the partial solar eclipse will be available here.

Local Viewing Opportunity

Von Braun Astronomical Society (VBAS) is partnering with the U.S. Space & Rocket Center® on Thursday, October 23, 2014, from 5 p.m. until sundown, for the observance of the partial solar eclipse. Join astronomers in the Davidson Center for Space Exploration parking lot to discuss the phenomenon and observe the solar eclipse through the telescopes. There will be visible-light viewing telescopes to see any sunspots, and special telescopes with hydrogen-light viewing in order to see the prominences at the edge of the sun.

The telescopes are equipped with filters for safe viewing of the sun.  Never look at the Sun directly!  Attempting to look directly at the sun without such special filters is harmful to the eyes.
This event is free and open to the public.