A Partial Lunar Eclipse Ushers in Eclipse Season

partial lunar eclipse
partial lunar eclipse
The partial lunar eclipse of June 4th, 2012. Credit: Dave Dickinson

Live on the wrong continent to witness the August 21st total solar eclipse? Well… celestial mechanics has a little consolation prize for Old World observers, with a partial lunar eclipse on the night of Monday into Tuesday, August 7/8th.

A partial lunar eclipse occurs when the Moon just nicks the inner dark core of the Earth’s shadow, known as the umbra. This eclipse is centered on the Indian Ocean region, with the event occurring at moonrise for the United Kingdom, Europe and western Africa and moonset/sunrise for New Zealand and Japan. Western Australia, southern Asia and eastern Africa will see the entire eclipse.

The path of the Moon through the Earth’s shadow Monday night. Credit: adapted from NASA/GSFC/Fred Espenak

The penumbral phase of the eclipse begins on August 7th at 15:50 Universal Time (UT), though you probably won’t notice a slight tea colored shading on the face of the Moon until about half an hour in. The partial phases begin at 17:23 UT, when the ragged edge of the umbra becomes apparent on the southeastern limb of the Moon. The deepest partial eclipse occurs at 18:22 UT with 25% of the Moon submerged in the umbra. Partial phase lasts 116 minutes in duration, and the entire eclipse is about five hours long.

The viewing prospects for the partial lunar eclipse. Credit: NASA/GSFC/Fred Espenak.

This also marks the start of the second and final eclipse season for 2017. Four eclipses occur this year: a penumbral lunar eclipse and annular solar eclipse this past February, and this month’s partial lunar and total solar eclipse.

Eclipses always occur in pairs, or very rarely triplets with an alternating lunar-solar pattern. This is because the tilt of the Moon’s orbit is inclined five degrees relative to the ecliptic, the plane of the Earth’s orbit around the Sun. The Moon therefore misses the 30′ wide disk of the Sun and the 80′ – 85′ wide inner shadow of the Earth on most passes.

partial lunar eclipse
The partial lunar eclipse of April 26th, 2013. Image credit and copyright: Henna Khan

Fun fact: at the Moon’s 240,000 mile distance from the Earth, the ratio of the apparent size of the Moon and the shadow is approximately equivalent to a basketball and a hoop.

When celestial bodies come into alignment, however, things can get interesting. For an eclipse to occur, the nodes – the point where the Moon’s orbit intersects the ecliptic – need to align with the position of the Moon and the Sun. There are two nodes, one descending with the Moon crossing the ecliptic from north to south, and one ascending. The time it takes for the Moon to return to the same node (27.2 days) is a draconitic month. Moreover, the nodes are moving around the Earth due to drag on the Moon’s orbit mainly by the Sun, and move all the way around the zodiac once every 18.6 years.

Got all that? Let’s put it into practice with this month’s eclipses. First, the Moon crosses its descending node at 10:56 UT on August 8th, just over 16 hours after Monday’s partial eclipse. Two weeks later, however, the Moon crosses ascending node just under eight hours from the central conjunction with the Sun, and a total solar eclipse occurs.

Tales of the Saros

The August 7th lunar eclipse is member number 62 of the 83 lunar eclipses in saros series 119, which started on October 14th, 935 AD and will end with a final shallow penumbral eclipse on March 25th, 2396 AD. If you witnessed the lunar eclipse of July 28th, 1999, then you saw the last lunar eclipse in the same saros. Saros 119 produced its last total lunar eclipse on June 15th, 1927.

The next lunar eclipse, a total occurs on January 31st, 2018, favoring the Pacific rim regions.

 

Partial lunar eclipses have occasionally work their way into history, usually as bad omens. One famous example is the partial lunar eclipse of May 22nd, 1453 which preceded the Fall of Constantinople to the Ottoman Turks by a week. Apparently, a long standing legend claimed that a lunar eclipse would be the harbinger of the fall of Byzantium, and the partially eclipsed Moon rising over the besieged city ramparts seemed to fulfill the prophecy.

In our more enlightened age, we can simply enjoy Monday’s partial lunar eclipse as a fine celestial spectacle. You don’t need any special equipment to enjoy a lunar eclipse, just a view from the correct Moonward facing hemisphere of the Earth, and reasonably clear skies.

See the curve of the Earth’s shadow? This is one of the very few times that you can see that the Earth is indeed round (sorry, Flat Earthers) with your own eyes. And this curve is true for observers watching the Moon on the horizon, or high overhead near the zenith.

This month’s lunar eclipse occurs in the astronomical constellation of Capricornus. The Moon will also occult the +5th magnitude star 29 Capricorni for southern India, Madagascar and South Africa shortly after the eclipse.

The viewing footprint for the 29 Capricorni occultation shortly after the eclipse. Credit: Occult 4.2.

Finally, anyone out there planning on carrying the partial lunar eclipse live, let us know… curiously, even Slooh seems to be sitting this one out.

Update: we have one possible broadcast, via Shahrin Ahmad (@shahgazer on Twitter). Updates to follow!

The final eclipse season for 2017 is now underway, starting Monday night. Nothing is more certain in this Universe than death, taxes and celestial mechanics, as the path of the Moon now sends it headlong to its August 21st destiny and the Great American Total Solar Eclipse.

-We’ll be posting on Universe Today once more pre-total solar eclipse one week prior, with weather predictions, solar and sunspot activity and prospects for viewing the eclipse from Earth and space and more!

-Read more about this year’s eclipses in our 2017 Guide to 101 Astronomical Events.

-Eclipse… science fiction? Read our original eclipse-fueled tales Exeligmos, Shadowfall, Peak Season and more!

NASA to Use Converted Bombers to Chase Totality

WB57B total solar eclipse
A NASA WB-57F on the ramp at Ellington Field near Houston ready to chase totality next month during the historic August 21st total solar eclipse. Credit: NASA/JSC

In a classic swords-to-plowshares move, two converted WB-57F aircraft flown by NASA’s Airborne Science Program will greet the shadow of the Moon as it rushes across the contiguous United States on Monday, August 21st on a daring mission of science.

“We are going to be observing the total solar eclipse with two aircraft, each carrying infrared and visible light cameras taking high definition video,” Southwest Research Institute (SwRI) Principal Investigator on the project Amir Caspi told Universe Today. “These will be the highest quality observations of their kind to date, looking for fast dynamic motion in the solar corona.”

Total solar eclipses provide researchers with a unique opportunity to study the solar corona – the ghostly glow of the Sun’s outer atmosphere seen only during totality. NASA plans a battery of experiments during the eclipse, including plans to intercept the Moon’s shadow using two aircraft near the point of greatest totality over Carbondale, Illinois. Flying out of Ellington Field near Houston Texas and operated by NASA’s Johnson Spaceflight Center, NASA is the only remaining operator of the WB-57F aircraft.

NASA fleet total solar eclipse
Group photo of NASA’s three WB-57F aircraft fleet. Credit: NASA/Robert Markowitz

Flying at an altitude of 50,000 feet, the aircraft will intercept the 70 mile wide shadow of the Moon. The shadow will be moving at 1,400 miles per hour – twice the speed of sound – versus the WB-57F aircraft’s max speed of 470 miles per hour. The flight will extend the length of totality from the 2 minutes 40 seconds seen on the ground, to a total of about 8 minutes between the two aircraft.

The two converted WB-57F Canberra tactical bombers will track the eclipse using DyNAMITE (Day Night Airbourne Motion Imagery for Terrestrial Environments), two tandem gimbal-mounted 8.7-inch imagers, one for visible light and one for infrared. These are located in the nose of the aircraft and will shoot 30 frames per second.

DyNAMITE
The new DyNAMITE system mounted in the nose of NASA’s WB-57F aircraft. Credit: NASA/Amir Caspi

This system was originally designed about a decade ago to chase down the U.S. Space Shuttle during reentry following the 2003 Columbia disaster and has, on occasion, provided amazing footage SpaceX Falcon-9 Stage 1 returns during reentry.

DyNAMITE total solar eclipse
The WAVE system, a precursor to DyNAMITE, seen up close. NASA/JSC

The solar corona is about as bright as the Full Moon, and the team plans to make a precise ‘map’ of the solar corona in an effort to understand just how the corona interacts with the solar photosphere and the chromosphere. Of particular interest is understanding how wave energy and ‘nanoflares’ heat the solar corona.

“What we’re hoping to learn is what makes the corona so hot, with temperatures of 1 to 2 million degrees Celsius — or even 4 to 10 million degrees Celsius in some regions — far hotter than the photosphere below,” Caspi told Universe Today. “What keeps it organized in terms of structure? Why don’t we see a snarled, tangled mess?”

As a secondary objective, the team will also make observations of the planet Mercury in the infrared 30 minutes before and after totality, located 11 degrees to the east of the Sun during the eclipse. Mercury never strays far from the Sun, making it a tough target to study in the infrared as seen from the Earth.

Totality total solar eclipse
Totality! Credit: Alan Dyer/Amazing Sky Photography.

And of course, all of this has to happen during the scant few minutes up to and during totality. Each aircraft will fly just inside opposite ends of the shadow of the Moon in a challenging long distance precision formation.

The WB-57F aircraft will also participate in a tertiary objective, hunting for Vulcanoid asteroids near the Sun during the eclipse. Though the 19th century idea of a tiny inter-Mercurial world perturbing Mercury’s orbit was banished to the dust bin of astronomical history by Einstein’s general theory of relativity, there’s still room for undiscovered asteroids dubbed ‘Vulcanoids’ close in to the Sun. NASA flew observations hunting for Vulcanoids aboard modified F-18 Hornet aircraft in 2002 scanning twilight realms near the Sun, and came up with naught.

Eclipse chaser Landon Curt Noll noted during an interview with Universe Today in 2015 that NASA’s Solar Heliospheric Observatory SOHO mission has pretty much ruled out objects brighter than +8th magnitude near the Sun, which translates into asteroids 60 kilometers in diameter or larger.

“We have searched down to magnitude +13.5,” Noll told Universe Today. “Assuming the objects are ‘Mercury like’ in reflectivity (in) the Vulcanoid zone (0.08 to 0.18 AU from the Sun), the search has looked for and failed to find objects as small as 2 to 6 kilometers in diameter.” NASA’s Mercury Messenger carried out a similar search en route to the innermost planet.

Stellarium total solar eclipse
Mercury versus the Sun during totality. Credit: Stellarium.

Knoll has scoured the sky near the eclipsed Sun with a specialized near-infrared telescope rig during the 2006 total solar eclipse over Libya. Next month, he plans to continue his quest from a site near Jackson Hole, Wyoming.

The action leading up to the the long awaited August 21st total solar eclipse begins at 17:16 Universal Time (UT)/ 10:16 AM Pacific Daylight Saving Time (PDT), when the Moon’s dark inner shadow or umbra touches down along the Oregon Pacific coast. From there, the 70 mile wide shadow will race eastward, gracing 14 states (just nicking Iowa and Montana) before departing land over the Atlantic coast of South Carolina 92 minutes later. Viewers along the path will witness a maximum totality of 2 minutes and 40 seconds, centered on a location very near Carbondale, Illinois. Millions are expected to make the pilgrimage to the eclipse path, while those outside the path in the remainder of North America as well as northern South America, western Africa, Europe and northeast Asia will see varying levels of a partial solar eclipse.

eclipse maps total soalar eclipse
The August 21st total solar eclipse over the United States. Credit: Michael Zeiler/Eclipse Maps

This is the end of a long “total solar eclipse drought” for the United States, marking the first time totality touched the continental United States since February 26, 1979, (totality crossed Hawaii on July 11th, 1991). The last total solar eclipse to cross the United States from coast-to-coast was June 8th, 1918.

NASA has a long history of airborne astronomy campaigns. Noll notes that NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) flying observatory based out of Armstrong research center would make an ideal platform for Vulcanoid hunting during totality. Looking at SOFIA’s flight schedule, however, reveals no plans to carry out such a chase on August 21st. SOFIA’s predecessor, the Kuiper Observatory built into a U.S. Air Force C-141 Starlifter discovered the rings of Uranus during a stellar occultation in 1977.

“This is the first use of DyNAMITE and NASA’s WB-57F platform for astronomy,” Caspi told Universe Today. “This showcases the potential for the platform for possible future observations.”

The DyNAMITE/WB-57B campaign will also be part of the live NASA TV webcast on eclipse day.

Airborne total solar eclipse chasing goes all the way back to August 19th 1887, when Dmitri Mendeleev (he of the periodic table) observed totality from aloft. There’s a great old video of an effort to chase a 1925 total solar eclipse using the airship the USS Los Angeles:

A team also chased a total solar eclipse across North Africa on June 30th, 1973 aboard a supersonic Concorde:

Today, you can even book a ticket for an eclipse-chasing experience aloft. Alaska Airlines plans to attempt to duplicate its 2016 success, and will once again chase totality with a lucky few observers aboard next month.

As for us, we’re planning on watching the eclipse from terra firma at the Pisgah Astronomical Research Institute (PARI) in North Carolina while intrepid researchers fly high above. Watch for our complete eclipse guide out around July 21st on Universe Today and an update on weather prospects, solar activity etc. about a week prior. Finally, we’ll have an after action report out post total solar eclipse, with reader images from across the country.

-This promises to be a total solar eclipse for the ages. Don’t miss the Great American Eclipse!

-Also, be sure to check out the Eclipse MegaMovie Project.

-Read more about the August 21st total solar eclipse and the true tale of Vulcan, Totality and Edison’s Chickens in our free e-guide to 101 Astronomical Events for 2017, out from Universe Today.

-Be sure to read our original tales of eclipse science fiction.

Join the Eclipse MegaMovie 2017 Chronicling the August Total Solar Eclipse

Eclipse Diamond Ring
Eclipse Diamond Ring
The November 2012 total solar eclipse as seen from Australia. The Eclipse Megamovie project hopes to capture a similar extended view. Image credit and copyright: Alan Dyer/Amazing Sky Photography.

Ready for the “Great American Eclipse?” We’re now less than six months out from the long-anticipated total solar eclipse spanning the contiguous United States from coast-to-coast. And while folks are scrambling to make last minute plans to stand in the path of totality on Monday, August 21st 2017, a unique project named the Eclipse Megamovie 2017 seeks seeks to document the view across the entire path.

The Project: Sponsored by Google’s Making & Science Initiative and led by Scott McIntosh from the National Center for Atmospheric Research’s High Altitude Observatory and Hugh Hudson from the University of California at Berkeley, the Eclipse Megamovie Project seeks to recruit 1,500 observers stationed across the eclipse path from Oregon to South Carolina. Although individual observers will only experience a maximum totality length of 2 minutes and 40 seconds, the complete span of the Eclipse Megamovie will last 90 minutes, compiled using observer images from coast-to-coast.

Mega movie
Getting ready for the Eclipse Megamovie project. Credit: Eclipse Megamovie Project.

“The movie is a tool for scientific exploration,” Hudson said in a recent University of California at Berkeley press release. “We’ll be collecting this level of data for the first time, from millions of observers, and it will be a valuable archive. But we don’t know what we’ll see or what we’ll learn about the interactions between the chromosphere and the corona.”

One portion of the project will have trained volunteers image the Sun from along the eclipse path using DSLRs, while another portion of the project will feature smartphone users imaging totality using a forthcoming Eclipse Megamovie app for a full length lower resolution movie.

Bikers and Baily’s Beads

The only total solar eclipse for 2017, totality for this eclipse occurs along a 114 kilometer-wide path touching on 12 states. Millions live within an easy day drive of the eclipse path, so expect lots of general public interest leading up to eclipse day. August is RV and camping season, so expect camplots to fill up quickly as well. The eclipse also occurs just over a week after the annual Biker’s Rally in Sturgis, South Dakota, affording motorcyclists a chance to stand in the shadow of the Moon en route to the annual pilgrimage.

Great American Eclipse
The path of the August 21st, 2017 eclipse across the United States. Credit: Michael Zeiler/Eclipse-Maps.

The last total solar eclipse to cross one of the 50 United States graced Hawaii on July 11th, 1991, and the last time the umbra of the Moon touched down over the lower 48 states was on February 26th, 1979 across the United States northwest. But you have to go all the way back over almost a century ago to June 8th, 1918 to find an eclipse featuring totality which exclusively spanned the United States from sea to shining sea.

Observers have chased after the umbra seeking to extend fleeting totality before. Eclipse chasers documented the January 24th, 1925 eclipse from aloft aboard a dirigible over New York City. On June 30th, 1973, a supersonic Concorde flight chased the umbra of the Moon across northern Africa, extending totality out to 74 minutes.

The team was also on hand to perform a dry run test of the Megamovie Project at this past weekend’s annular eclipse which crossed South America, the Southern Atlantic and Africa and reports that the field test of the promised project app by Mark Bender worked admirably, and the Eclipse Megamovie App should be available to the general public soon.

Baily's Beads
A mosaic of the 2016 total solar eclipse, depicting the evolution of Baily’s Beads before and after totality. Image credit and copyright: Steed Joy.

What sort of science can such a project offer? What is left to learn from a total solar eclipse after centuries of scientific study? Well, some of the most accurate measurements of the solar diameter and the size and shape of the Sun have been made during solar eclipses. A long movie may also reveal streamers and development of the solar corona, the ethereal pearly white glowing outer atmosphere surrounding the Sun. About half as bright as a Full Moon, we only get a brief glimpse of the corona during totality. Also, the Eclipse Megamovie will get another shot at the project in April 2024, when another eclipse crosses the United States from Texas to Maine.

The Eclipse Megamovie is taking volunteers now. The gear setup required is simple, and you might have what’s needed to image the eclipse laying around already.

DSLR
Got a tripod-mounted, zoom lens equipped DSLR? Photo by author.

You’ll need a DSLR camera with a sturdy tripod, a zoom or fixed lens of 300mm focal length or better, and an ability to nail down your GPS location and the time to the nearest second. Once the volunteers are selected, training will be provided to include GPS and time stamping images, flat-fielding and more.

Phone apps will readily supply the GPS part. For time, I’d go with with WWV Radio, which broadcasts a continuous audio time hack out of Fort Collins, Colorado. This is in Universal Time, and has an accuracy of better than a second better than online time sources, which occasionally lag due to spurious web connections.

Keep in mind, you’ll be photographing the eclipsed Sun during very brief moments of totality. You’ll need to have approved solar glasses and filters in place during all partial phases leading up to and immediately after the eclipse. The Eclipse Megamovie project also hopes to catch sight of the Bailey’s Beads phenomenon as final streamers of sunlight pour through the lunar valleys, giving the illusion known as the Diamond Ring effect.

TSE2017
An animation of the August 21st, 2017 total solar eclipse. A.T. Sinclair/NASA/GSFC

And us? We’ll be casting our hubris at the Universe and catch the eclipse from Columbia, South Carolina. We’re heeding the advice of veteran eclipse chasers, and simply enjoying our first eclipse, and imaging our second, though we may sneak in a few shots for the Eclipse Megamovie project. Universe Today publisher Fraser Cain and astronomer and AstronomyCast host Pamela Gay will lead a group watching from southern Illinois, and we’ve also heard from many other observers from around the world who’ll be visiting the U.S. the August… where will you be?

And we’ve already got a spot picked out for 2024, as the next total solar eclipse crosses Aroostook County and our hometown of Mapleton, Maine… hey, you can never start planning too early, right?

Get set for an eclipse for the ages, and be sure to contribute to the Eclipse Megamovie Project.

-Read about all eclipses, comets, occultations and more for the year in our guide to 101 Astronomical Events for 2017, free from Universe Today.

-Eclipse… science fiction? Check out our original eclipse-fueled sci-fi tales Exeligmos, Shadowfall, the Syzygy Gambit, Peak Season and more.

Our Guide to This Week’s ‘Ring of Fire’ Annular Eclipse

Ring of Fire

In Africa this week? The final solar eclipse of 2016 graces the continent on Thursday, September 1st. This eclipse is annular only, as the diminutive Moon fails to fully cover the disk of the Sun.

The 99.7 kilometer wide path crosses the African countries of Gabon, Republic of the Congo, Democratic Republic of the Congo, Tanzania, Mozambique and Madagascar. The antumbra (the ‘ring of fire path of the shadow annulus as viewed from Earth) touches down in the southern Atlantic at 7:20 Universal Time (UT) on September 1st, before racing across Africa and departing our fair planet over the Indian Ocean over four hours later at 10:55 UT. Partial phases for the eclipse will be visible across the African continent as far north as southern Morocco, Egypt and the southwestern portion of the Arabian peninsula.

Path. Credit: Xavier Jubier.
The path of this week’s eclipse across Africa. Credit: Xavier Jubier.

Tales of the Saros

This eclipse is member 39 of 71 solar eclipses for saros 135, which runs from July 5th, 1331 to August 17th, 2593. This series finally produces its first total solar eclipse on March 29, 2359.

A daguerreotype of an annular eclipse from 1854, part of the same saros 154 cycle. Public domain image.
A daguerreotype of an annular eclipse from 1854, part of the same saros 154 cycle. Public domain image.

Annular eclipses occur when the Moon is too distant to cover the Sun as seen from the Earth. The Moon reaches apogee, or its most distant point from the Earth on September 6th, just five days after New and the September 1st eclipse.

How common (or rare) are solar eclipses, annular or total? It’s worth noting that as the 2017 total solar eclipse crossing the contiguous United States approaches, creationist websites are again promoting the idea that the supposed ‘perfection’ of solar eclipses is evidence for intelligent design. If solar eclipses are an example of a higher plan to the cosmos, they’re not a very good one… in fact, in our current epoch, partial eclipses, to include annulars, are much more prevalent. If, for example, the Moon’s orbit was aligned with the ecliptic, we’d see two eclipses – one lunar and and one solar – every month, a much rarer circumstance… a creator could have really used that to really get our attention. And Earth isn’t alone in hosting total solar eclipses: in our own solar system, you can make a brief visit to Jupiter’s large moons and also witness total solar eclipse perfection.

Unlike a total solar eclipse, proper eye protection must be worn throughout all stages of an annular eclipse. We witnessed annularity from the shores of Lake Erie back in 1994, and can attest that a few percent of the Sun is still surprisingly bright. The tireless purveyors of astronomy over at Astronomers Without Borders are working to distribute eclipse glasses to schools and students along the eclipse path.

An animation of Thursday's eclipse. Credit: NASA/GSFC.
An animation of Thursday’s eclipse. Credit: NASA/GSFC.

Are you in the path of this week’s annular eclipse? Let us know, and send those images in to Universe Today on Flickr.

We’ll most likely see more than a few images of the eclipse from space as well. And no, we’re not talking about the cheesy composite that now makes its rounds during every eclipse… solar observing satellites to include the European Space Agency’s Proba-2 and the joint JAXA/NASA Hinode mission typically capture several successive eclipses as they observe the Sun from their vantage point in low Earth orbit.

At this stage, we only know of one webcast set to broadcast the eclipse live: the venerable Slooh website.

Let us know if you’re planning on setting up an ad hoc live webcast of the eclipse, even from outside the path of annularity.

And of course, the big question on every eclipse-chaser’s mind is: when’s the next one? Well, we’ve got a subtle penumbral eclipse on September 16th, 2016, and then the next solar eclipse is another annular favoring Argentina, Chile and the west coast of southern Africa on February 26th, 2017.

Don’t miss this week’s annular solar eclipse, either live online or in person, for a chance to marvel at a celestial phenomenon we all share in time and space.

-Eclipse… science fiction? Yup… read Dave Dickinson’s eclipse-fueled tales Peak SeasonExeligmos, Shadowfall and The Syzygy Gambit.

One Year to the 2017 Total Solar Eclipse

https://www.flickr.com/photos/auraluu/7085004603/in/photolist-bN5v2M-dufbuU-pzUHQi-nZQkxQ-6KdhJ7-9TLjD4-dtvX13-pidJNx-dtvUxY-dxAA8r-n8uzjn-hx1CzU-du9zKv-c4eHhw-F1szSh-hx2yTc-dv7Y5W-dubgHK-du9zB6-FvPkNQ-drNyGZ-Eg3Msj-F4kfHb-zpuHFU-yUCmvN-yuSXP5-DqsCRp-zfU1bR-zbbFV9-FrtBYE-hdVRQm-rkh8fd-dufbHG-6KGxbK-dufbmf-du9zQe-ryZmAb-FtsHpn-EAUwcK-Ct6Fma-6KLF1b-FiThUB-EEgQjh-E8uHFM-yUC28b-rqtfQ3-yTR8jt-tsa14t-rHcxrz-rXwEhJ

One. More. Year. Quick; where will you be this time next year on August 21st, 2017? We’re now just one year out this weekend from a fine total solar eclipse gracing the United States from coast to coast. If you think one year out is too early to start planning, well, umbraphiles (those who chase the shadow of the Moon worldwide) have been planning to catch this one now for over a decade.

The shadow of the March 9th, 2016 solar eclipse as seen from the Himawari-8 Earth-observing satellite. image credit: JAXA/JMA/Himawari/CIMSS
The shadow of the March 9th, 2016 solar eclipse (the dark spot on the right) as seen from the Himawari-8 Earth-observing satellite. Image credit: JAXA/JMA/Himawari/CIMSS.

Get set for the Great American Eclipse. The last time a total solar eclipse made landfall over a U.S. state was Hawaii on July 11th, 1991, and the path of totality hasn’t touched down over the contiguous ‘Lower 48’ United States since February 26th, 1979. And you have to go all the way back over nearly a century to June 8th, 1918 to find an eclipse that exclusively crossed the United States from the Pacific to the Atlantic Coast.

The path of the 2017 total solar eclipse across the U.S. image credit and copyright: Michael Zeiler/The GreatAmercianEclipse
The path of the 2017 total solar eclipse across the U.S. Image credit and copyright: Michael Zeiler/The GreatAmercianEclipse

Totality for the August 21st, 2017 eclipse crosses over many major cities, including Columbia South Carolina, Nashville, St. Louis and Salem, Oregon. The inner shadow of the Moon touches on 15 states as it races across the U.S. in just over an hour and a half. The length of totality is about 2 minutes in duration as the shadow makes landfall near Lincoln City, Oregon, reaches a maximum duration of 2 minutes, 42 seconds very near Carbondale, Illinois, and shrinks back down to 2 minutes and 35 seconds as the shadow heads back out to sea over Charleston, South Carolina.

The eclipse will be a late morning affair in the northwest, occurring at high noon over western Nebraska, and early afternoon to the east. ‘Getting your ass to totality,’ is a must. “But I’ve seen a partial solar eclipse,” is a common refrain, “aren’t they all the same?”

An animation of the 2017 eclipse.
An animation of the 2017 eclipse.

Nope. We witnessed the May 10th, 1994 annular eclipse from the shores of Lake Erie, and can tell you that even less than 1% of the Sun’s intensity is still pretty bright, a steely blue luminosity equivalent to a cloudy day.

We crisscrossed the United States along the eclipse path back in 2014, chronicling preparations in towns such as Columbia and Hopkinsville, Kentucky. Last minute accommodation is already tough to come by, even one year out. Cabins in the Land Between the Lakes region near Paducah, Kentucky, for example, were booked full as soon as the August 21st date became available. Think Mardi Gras and DragonCon, rolled into one. Hopkinsville also has an annual Roswell-style UFO-fest on the same date, celebrating the 1955 Kelly-Hopkinsville UFO incident.

Will it be ‘umbraphiles versus aliens?’

Out west, enticing locales include the Grand Teton National Park and Jackson Hole, Wyoming and the northern edge of the Craters of the Moon National Monument site in Idaho. It’s also worth noting that the western United States is a better bet cloud cover-wise, as afternoon summer thundershowers tend to be the norm for the southeast during late August.

Millions live within an easy day drive of the eclipse path, and it happens during prime camping season, to boot. The annual Sturgess motorcycle rally held near Rapid City, South Dakota is just one week prior to totality, and bikers returning from the pilgrimage southward could easily stop to greet the Earth’s shadow on the road home.

2017 Eclipse Panorama from Michael Zeiler on Vimeo.

There’s been talk that Cosmoquest may mount an eclipse expedition based out of Nashville, Tennessee (more to come on that).

Maintaining mobility is the best bet. Our master plan is to return to the States a week or so prior, rent a camper van from Vegas, and head northward. Like millions of Americans, this will be our first total solar eclipse, and the event promises to spark a whole new generation of umbraphiles. And stick around just seven more years, and totality will again cross the United States on August 8th, 2024 from the southwest to the northeast. The Illinois, Missouri and Kentucky tri-state region sees this eclipse as well. This one is special for us, as it crosses over our hometown of Presque Isle, Maine. I remember looking up the next total solar eclipse over northern Maine as a kid, way back when, and figuring out just how old I would be. The top of Mount Katahdin and selected sites along the Maine Solar System model would all be choice locales to view this one. Check out this great old vid of the aforementioned 1979 eclipse over the U.S.:

We also plan on taking the veteran eclipse-chaser’s mantra of ‘experience your first eclipse; but photograph your second one.’ to heart. Lots of fascinating projects are afoot leading up to the 2017 total solar eclipse, including The Eclipse MegaMovie Project to produce a complete video documentary of the eclipse path, plans by a student group to fly and observe the eclipse from balloons during totality, proposals to replicate famous eclipse experiments and more. It’s also worth noting that the bright star Regulus will sit just one degree from the Sun during totality… perhaps someone will manage to measure its deflection via General Relativity in a manner similar to Sir Arthur Eddington’s famous 1919 observation?

Unlike the paths of most eclipses, which seem to have an affinity for wind-swept tundra or remote swaths of desert, this one is sure to draw in the ‘astronomy-curious’ and may just be the most witnessed total solar eclipse in history.

Here’s some eclipse tales and facts to ponder leading up to totality. If you caught the August 11th, 1999 eclipse across Europe, then you saw the last eclipse in the same saros series 145. If you caught the eclipse before that in the same series on July 31st, 1981 across northeast Asia, then you’ll complete a 54 year long triple-saros period after seeing next summer’s eclipse, known as an exeligmos. This cycle also brings the eclipse path very nearly back around to the same longitude.

Stellarium
Regulus near the  eclipsed Sun next August. Credit: Stellarium.

The Sun is about 400 times larger than the Moon in diameter, but the Moon is 400 times closer. We’ve actually heard this fact tossed out as evidence for intelligent design, though it’s just a happy celestial circumstance of our present era. In fact, annular eclipses are now slightly more common than totals in our current epoch, and will continue to become more so as the Moon slowly recedes from the Earth. Just under a billion years ago, the very first annular eclipse of the Sun as seen from the Earth occurred, and 1.4 billion years hence, the Earth will witness one last brief total eclipse.

But you won’t have to wait that long. Don’t miss the greatest show in the universe next August!

-Check out Michael Zeiler’s (@EclipseMaps) 10-foot long strip map of the entire eclipse path.

-Eclipses, both lunar and solar have played a role in history as well.

-Curious about eclipses in time and space? Read our eclipse-fueled sci-fi tales, Exeligmos, The Syzygy Gambit and Shadowfall, with more to come!

Chasing the Shadow: Our Guide to the March 9th Total Solar Eclipse

Ready for the ultimate in astronomical events? On the morning of Wednesday, March 9th, the Moon eclipses the Sun for viewers across southeast Asia.

Many intrepid umbraphiles are already in position for the spectacle. The event is the only total solar eclipse of 2016, and the penultimate total solar eclipse prior the ‘Big One’ crossing the continental United States on August 21st, 2017.

Image credit: Great American Eclipse/Michael Zeiler
The path of tomorrow’s eclipse. Image credit: Great American Eclipse/Michael Zeiler

Tales of the Saros

This particular eclipse is member 52 of 73 eclipses in saros cycle 130, which runs from 1096 AD to 2394. If you saw the total solar eclipse which crossed South America on February 26th, 1998, then you caught the last solar eclipse from the same cycle.

Image credit: NASA/GSFC/A.T. Sinclair
An animation of the event. Image credit: NASA/GSFC/A.T. Sinclair

Weather prospects are dicey along the eclipse track, as March is typically the middle of monsoon season for southeast Asia. Most eclipse chasers have headed to the islands of Indonesia or cruises based nearby to witness the event. The point of greatest eclipse lies off of the southeastern coast of the Philippine Islands in the South China Sea, with a duration of 4 minutes and 10 seconds. Most observers, however, will experience a substantially shorter period of totality. For example, totality lasts only 2 minutes and 35 seconds over island of Ternate, where many eclipse chasers have gathered. The Sun will be 48 degrees above the horizon from the island during totality.

A great place to check cloud cover and weather prospects along the eclipse track is the Eclipsophile website.

Image credit; SkippySky
A dicey sky: prospects for cloud cover over Australia. Image credit; SkippySky

The umbra of the Earth’s Moon will sweep across Sumatra at sunrise and across the island of Borneo, to landfall one last time for Indonesia over the island of North Maluku before sweeping across the central Pacific. This eclipse is unusual in that it makes landfall over a very few countries: the island nation of Indonesia, and just a few scattered atolls in Palau and Micronesia.

Partial phases of the eclipse are also visible from India at sunrise, across northeast Asia along the northernmost track, to central Australia in the south, and finally, to southern Alaskan coast at sunset. Honolulu Hawaii sees a 65% partial solar eclipse in the late afternoon on March 8th.

Expect great views, both from Earth and from space. We typically get images from solar observing spacecraft, to include the joint NASA/JAXA Hinode mission, and the European Space Agency’s PROBA-2 spacecraft. Both are in low-Earth orbit, and see a given eclipse as a swift, fleeting event. Other solar observatories—such as the Solar Heliospheric Observatory and the Solar Dynamics Observatory—occupy a different vantage point in space, and miss the eclipse.

Image credit: Starry Night Education Software
The orientation of the Sun and planets at totality (click to enlarge). Image credit: Starry Night Education Software

As of this writing, we know of several folks that have made the journey to stand in the path of totality, to include Sharin Ahmad (@Shagazer), Michael Zeiler (@GreatAmericanEclipse) and Justin Ng.

Good luck and clear skies to all observers out there, awaiting darkness in the path of totality.

Live in the wrong hemisphere? There are several live webcasts planned from the eclipse zone:

NASA and the National Science Foundation are working with a team from San Francisco’s Exploratorium to bring a live webcast of the eclipse from the remote atoll island of Woleai, Micronesia. The feed starts at 7:00 EST/0:00 Universal Time (UT) and runs for just over three hours. You can follow the exploits of the team leading up to show time here.

The venerable Slooh will also feature a webcast of the eclipse with astronomer Paul Cox from Indonesia running for three hours starting at 6:00 PM EST/23:00 UT.

A view of the partial phases of the eclipse from the Hong Kong science center also starts at 5:30 PM EST/22:30 UT:

Don’t forget: though the eclipse occurs on the morning of March 9th local time in southeast Asia, the path crosses the International Dateline, and the webcasts kick off on the evening of Tuesday March 8th for North America.

And hey, Alaska Airlines flight 870 from Anchorage to Honolulu will divert from its flight plan slightly… just to briefly intercept the Moon’s shadow (its already a fully booked flight!)

From there, 2016 features only two faint penumbral lunar eclipses on March 23rd and September 16th, and an annular solar eclipse crossing central Africa on September 1st.

We’ll be doing a post-eclipse round up, with tales from totality and the pics to prove it… stay tuned!

Got eclipse pictures to share? Send ’em to Universe Today… we just might feature them in our round up!

Don’t miss our eclipse-fueled science fiction tales: Exeligmos and Shadowfall.

Will the March 20th Total Solar Eclipse Impact Europe’s Solar Energy Grid?

The first eclipse of 2015 is coming right up on Friday, March 20th, and may provide a unique challenge for solar energy production across Europe.

Sure, we’ve been skeptical about many of the websites touting a ‘blackout’ and Y2K-like doom pertaining to the March 20th total solar eclipse as of late. And while it’s true that comets and eclipses really do bring out the ‘End of the World of the Week’ -types across ye ole web, there’s actually a fascinating story of science at the core of next week’s eclipse and the challenge it poses to energy production.

But first, a brief recap of the eclipse itself. Dubbed the “Equinox Eclipse,” totality only occurs over a swath of the North Atlantic and passes over distant Faroe and Svalbard Islands. Germany and central Europe can expect an approximately 80% partially obscured Sun at the eclipse’s maximum.

Credit
The magnitude of the March 20th solar eclipse across Europe. Credit: Michael Zeiler/GreatAmericanEclipse.com

We wrote a full guide with the specifics for observing this eclipse yesterday. But is there a cause for concern when it comes to energy production?

A power grid is a huge balancing act.  As power production decreases from one source, other sources must be brought online to compensate. This is a major challenge — especially in terms of solar energy production.

Residential solar panels in Germany. Credit: Wikimedia Commons/ Sideka Solartechnik.
Residential solar panels in Germany. Credit: Wikimedia Commons/ Sideka Solartechnik.

Germany currently stands at the forefront of solar energy technology, representing a whopping quarter of all solar energy capacity installed worldwide. Germany now relies of solar power for almost 7% of its annual electricity production, and during the sunniest hours, has used solar panels to satisfy up to 50% of the country’s power demand.

We recently caught up with Barry Fischer to discuss the issue. Fischer is the Head Writer at Opower, a software company that uses data to help electric and gas utilities improve their customer experience. Based on Opower’s partnerships with nearly 100 utilities worldwide, the company has amassed  the world’s largest energy dataset of its kind which documents energy consumption patterns across more than 55 million households around the globe.

A study published last week by Opower highlights data from the partial solar eclipse last October over the western United States. There’s little historical precedent for the impact that an eclipse could have on the solar energy grid. For example, during the August 11th, 1999 total solar eclipse which crossed directly over Europe, less than 0.1% of utility electricity was generated using solar power.

Credit:
Looking at the drop in power production during the October 2014 solar eclipse. Credit: Opower.

What they found was intriguing. Although the 2014 partial solar eclipse only obscured 30 to 50% of the Sun, solar electric production dropped over an afternoon span of nearly three hours before returning to a normal pattern.

Examining data from 5,000 solar-powered homes in the western United States, Opower found that during the eclipse those homes sent 41% less electricity back to the grid than normal. Along with a nearly 1,000 megawatt decline in utility-scale solar power production, these drop-offs were compensated for by grid operators ramping up traditional thermal power plants that were most likely fueled by natural gas.

No serious problems were experienced during the October 23rd, 2014 partial solar eclipse in terms of solar electricity production in the southwestern United States, though it is interesting to note that the impact of the eclipse on solar energy production could be readily detected and measured.

Credit
The projected effect of the March 20th eclipse on solar power production. Credit: Opower.

How does the drop and surge in solar power output anticipated for the March 20th eclipse differ from, say, the kind presented by the onset of night, or a cloudy day? “The impact of an eclipse can register broadly – and unusually rapidly – across an entire region,” Fischer told Universe Today. On a small scale, one area many be cloudy, while on a larger regional scale, other areas of clear or partly sunny skies can compensate. An eclipse — even a partial one — is fundamentally different, because the sudden onset and the conclusion are relatively uniform over a large region.

The March 20th event offers an unprecedented chance to study the effects of an eclipse on large-scale solar production up close. A study (in German) by the University of Applied Sciences in Berlin suggests that solar power production will fall at a rate 2.7 times faster than usual as the eclipse progresses over a span of 75 minutes. This is the equivalent of switching off one medium-sized power plant per minute.

The anticipated slingshot might be just as challenging, as  18 gigawatts of power comes back online at the conclusion of the eclipse in just over an hour. And as opposed to the 2014 eclipse over the U.S. which ended towards sunset, the key rebound period for the March 20th eclipse will be around local noon and during a peak production time.

Fischer also noted that “the second half of the partial solar eclipse will also pose a notable challenge” for the grid, as it is flooded with solar power production 3.5 times faster than normal. This phenomenon could also serve as a great model for what could occur daily on a grid that’s increasingly solar power reliant in the future, as energy production ramps up daily at sunrise. Such a reality may be only 15 years away, as Germany projects installed solar capacity to top 66 gigawatts by 2030.

Credit:
The Crescent Dunes Solar Energy Project outside of Tonopah, Nevada. Credit:  Wikimedia Commons/Amble. Licensed under a CC BY-SA 4.0 license.

What’s the anticipated impact projected for a future eclipse such as, say, the 2017 and 2024 total solar eclipses over the U.S.?

This eclipse may serve as a great dry run for modeling what could occur as reliance on solar energy production grows.

Such is the modern technical society we live in. It’s fascinating to think that eclipses aren’t only a marvelous celestial spectacle, but their effects on power production may actually serve as a model for the smart grids of tomorrow.

 

 

 

Our Complete Guide to the October 8th “Hunter’s Moon” Total Lunar Eclipse

October 2014 means eclipse season 2 of 2 for the year is upon us.

Don’t fear the ‘Blood Moon’ that’s currently infecting the web, but if you find yourself on the correct moonward facing hemisphere of the planet, do get out and observe the total lunar eclipse coming right up on the morning of Wednesday, October 8th. This is the second and final total lunar eclipse of 2014, and the second of four in a quartet series of lunar eclipses known as a tetrad.

And the good news is, the eclipse once again favors nearly all of North America. From the western U.S. and Canada, the Moon will be high in the western skies when partial phases begin early in the morning on October 8th. The western U.S., Canada and Alaska will see the entire 61 minute span of totality, just 18 minutes shorter than last April’s lunar eclipse. The Moon will be high in the sky during totality for the Hawaiian Islands, and viewers in Australia and the Pacific Far East will witness the eclipse in the evening hours.

Visibility
The visibility regions for the total lunar eclipse. Credit: NASA/GSFC/Espenak.

This lunar eclipse is part of saros 127, and marks number 42 of a series of 72 for that particular saros. If you witnessed the total lunar eclipse visible from North America and Europe on September 27th, 1996, you caught the last of the series, and if you catch the next eclipse in the saros on October 18th, 2032, you’ve earned a veteran lunar eclipse-watchers badge of seeing an exeligmos, or “triple saros” of eclipses.

The path of the Moon through the Earth’s umbra on October 8th. Adapted from NASA/GFSC.

Timings for key phases of the eclipse are as follows:

P1- Penumbral phase begins: 8:14 UT/4:14 EDT/1:14 PDT

U1- Umbral (partial) phase begins: 9:15 UT/5:14 EDT/2:14 PDT

U2- Totality begins: 10:24 UT/6:24 EDT/3:24 PDT

Mid-totality- 10:55 UT/6:55 EDT/3:55 PDT

U3- Totality ends: 11:25 UT/7:25 EDT/4:25 PDT

U4- Umbral phase ends: 12:35 UT/5:35 PDT

P4- Penumbral phase ends: 13:35/6:35 PDT

Not all total lunar eclipses are the same when it comes to color. Totality can appear anywhere from a dark brick color, as happened during the December 9th, 1992, eclipse following the eruption of Mount Pinatubo, when the Moon nearly disappeared during totality, to a bright coppery red, as seen during the April eclipse earlier this year. The Moon passes to the north of the dark central core of the Earth’ shadow next Wednesday, so expect a brighter than normal eclipse, especially along the Moon’s northeast limb. Grab a painter’s wheel and compare the eclipsed Moon to swatches of orange through red: what colors do you see? What you’re seeing is the combinations of all the world’s sunsets refracted into the cone of the Earth’s shadow, which is about three times the size of the Moon at its average distance as seen from Earth. Remember, the Moon is experiencing a total solar eclipse as we watch the lunar eclipse unfold!

Stellarium
The October 8th total solar eclipse as seen from the Apollo 11 landing site on the nearside of the Moon. Created using Stellarium.

This color can be quantified and described on what is known as the Danjon Scale, with 0 being a very dark eclipse with the Moon barely visible, to a 4, meaning a very bright eclipse.

And yes, each total lunar eclipse is now receiving the “Blood Moon” meme thanks to ye ole Internet. Expect the conspiracy-minded to note that this eclipse occurs on the Jewish holiday of Sukkot starting at sundown on the 8th, which isn’t really all that wondrous as the Jewish calendar is a luni-solar one, and total lunar eclipses have to occur during a Full Moon by definition. Wait long enough, and an occasional “Sukkot total lunar eclipse” does indeed occur.

Uranus occultation
The footprint of the October 8th occultation of Uranus by the Moon during totality. (Credit: Occult 4.1.0).

But a truly rare event does occur during this eclipse, as the Moon actually occults (passes in front of) the planet Uranus during totality for observers in northern Alaska and northeast Asia. The rest of us in the observing zone will see a near miss. Can you spy Uranus with binoculars near the lunar limb during totality? Another such rarity occurred during Shakespeare’s time on December 30th, 1591, involving Saturn and the eclipsed Moon, and another such odd occurrence transpires in 2344 A.D.

2344 eclipse
The circumstances of the 2344 eclipse/occultation. Credit: Starry Night, NASA/GSFC & Occult 4.0.1.

The brightest star to be occulted by the total eclipsed Moon as it crosses the constellation Pisces is +7.9th magnitude HIP 4231 for the northern U.S. and Canada.

And speaking of historical eclipses, there’s a Columbus Day tie-in with the phenomenon as well. Like many mariners of his day, Columbus was well-versed in celestial navigation, and used a total lunar eclipse to get a good one-time fix on his longitude at sea, an experiment that you can easily replicate. Columbus also wasn’t above using prior knowledge of an impending lunar eclipse to get himself and his crew out of a bind with the locals when the need arose.

An outstanding sequence of images taken during the April 15th, 2014 total lunar eclipse. Credit: Michael Zeiler (Eclipse-Maps) Used with permission.
An outstanding sequence of images taken during the April 15th, 2014, total lunar eclipse. Credit: Michael Zeiler (Eclipse-Maps) Used with permission.

Photographing an eclipse with a DSLR is as easy as shooting an image of the Moon. Try this a few evenings before the big event. A minimum focal length of 200mm is needed to render the Moon larger than a white dot in the image, and remember that the Moon is much darker during total eclipse, and you’ll need to step the exposure times rapidly down from 1/100th of a second to 2 to 4 seconds during totality.

A long-running effort by Sky & Telescope has been looking for amateur observations of precise crater contacts along the rim of the umbra in an effort to measure variations in the diameter of the Earth’s shadow.

starry night
The Moon versus Uranus as seen from Napa, California just past mid-eclipse on the morning of October 8th. Credit: Starry Night Education Software.

As always, weather prospects are the big question mark when it comes to eclipses. Typically, the southwestern U.S. experiences 13-20 clear days in the month of October; prospects worsen to the northwest, with an average of 3-12 days. We’ll be looking at resources such as NOAA, Skippy Sky and ClearSkyChart on the evenings leading up to the 8th. The great thing about a lunar eclipse is, you don’t need a 100% clear sky to see it: just a clear view of the Moon!

Up for a challenge? We’ve yet to see a capture of a shadow transit of the International Space Station in front of the eclipsed Moon. This time around, such a capture should be possible across southern coastal California and the Baja peninsula just minutes prior to the onset of totality.

Orbitron
A shadow pass of the International Space Station just prior to the onset of totality. Note the position of the Moon. Created using Orbitron.

Another bizarre catch, known as a selenelion — witnessing the end of lunar totality after sunrise — may just be possible across the northeastern U.S. into the Canadian Maritimes as the eclipsed Moon sets during totality. The more elevation you can get the better! This works because the Moon lingers a bit in the large shadow of the Earth, plus atmospheric refraction gives the low altitude Sun and Moon a slight boost.

Clouded out? On the wrong side of the planet? You can watch the eclipse online at the following links:

– Live views courtesy of Gialuca Masi and the Virtual Telescope starting at 10:00 UT on October 8th.

– A live webcast starting at 9:00 UT courtesy of Slooh:

– A Columbia State University broadcast, (time to be determined).

Planning an ad-hoc broadcast? Let us know!

And as the eclipse wraps up, the biggest question is always: When’s the next one? Well, lunar eclipse number three of the four eclipse tetrad occurs next year on April 4th, 2015… but in just two weeks time, the western United States and Canada will also witness a fine partial solar eclipse on Oct 23rd

Stay tuned!

Got images of the total lunar eclipse? Send ‘em in to Universe Today’s Flickr forum!

Interested in eclipse sci-fi? Check out our latest short stories Exeligmos and Shadowfall.

The Science Behind the “Blood Moon Tetrad” and Why Lunar Eclipses Don’t Mean the End of the World

 By now, you may have already heard the latest tale of gloom and doom surrounding the upcoming series of lunar eclipses.

This latest “End of the World of the Week” comes to us in what’s being termed as a “Blood Moon,” and it’s an internet meme that’s elicited enough questions from friends, family and random people on Twitter that it merits addressing from an astronomical perspective.

Like the hysteria surrounding the supposed Mayan prophecy back in 2012 and Comet ISON last year, the purveyors of Blood Moon lunacy offer a pretty mixed and often contradictory bag when it comes down to actually what will occur.

But just like during the Mayan apocalypse nonsense, you didn’t have to tally up just how many Piktuns are in a Baktun to smell a rat. December 21st 2012 came and went, the galactic core roughly aligned with the solstice — just like it does every year — and the end of the world types slithered back into their holes to look for something else produce more dubious YouTube videos about.

Here’s the gist of what’s got some folks wound up about the upcoming cycle of eclipses. The April 15th total lunar eclipse is the first in series of four total eclipses spanning back-to-back years, known as a tetrad. There are eight tetrads in the 21st century: if you observed the set total lunar eclipses back in 2003 and 2004, you saw the first tetrad of the 21st century.

The eclipses in this particular tetrad, however, coincide with the Full Moon marking Passover on April 15th and April 4th and the Jewish observance of Sukkot on October 8th and September 28th. Many then go on to cite the cryptic biblical verse from Revelation 6:12, which states;

“I watched as he opened the sixth seal. There was a great earthquake. The Sun turned black like sackcloth made of goat hair. The whole Moon turned blood red.”

Whoa, some scary allegory, indeed… but does this mean the end of the world is nigh?

I wouldn’t charge that credit card through the roof just yet.

First off, looking at the eclipse tetrads for the 21st century, we see that they’re not really all that rare:

21st century eclipse tetrads:

Eclipse #1 Eclipse #2 Eclipse #3 Eclipse #4
May 16th, 2003 November 9th, 2003 May 4th , 2004 October 28th, 2004
April 15th, 2014*+ October 8th, 2014 April  4th, 2015*+ September 28th, 2015
April 25th, 2032 October 18th, 2032 April 14th, 2033*+ October 8th, 2033
March 25th, 2043* September 19th, 2043 March 13th, 2044 September 7th, 2044
May 6th, 2050 October 30th, 2050 April 26th, 2051 October 19th, 2051
April  4th, 2061*+ September 29th, 2061 March 25th, 2062* September  18th, 2062
March 4th, 2072 August 28th, 2072 February 22nd, 2073 August 17th, 2073
March 15th, 2090 September 8th, 2090 March 5th, 2091 August 29th, 2091
*Paschal Full Moon
+Eclipse coincides with Passover

 

Furthermore, Passover is always marked by a Full Moon, and a lunar eclipse always coincides with a Full Moon by definition, meaning it cannot occur at any other phase. The Jewish calendar is a luni-solar based calendar that attempts to mark the passage of astronomical time via the apparent course that the Sun and the Moon tracks through the sky. The Muslim calendar is an example of a strictly lunar calendar, and our western Gregorian calendar is an example of a straight up solar one. The Full Moon marking Passover often, though not always, coincides with the Paschal Moon heralding Easter. And for that matter, Passover actually starts at sunset the evening prior in 2014 on April 14th. Easter is reckoned as the Sunday after the Full Moon falling after March 21st which is the date the Catholic Church fixes as the vernal equinox, though in this current decade, it falls on March 20th. Easter can therefore fall anywhere from March 22nd to April 25th, and in 2014 falls on the late-ish side, on April 20th.

To achieve synchrony, the Jewish calendar must add what’s known as embolismic or intercalculary months (a second month of Adar) every few years, which in fact it did just last month. Eclipses happen, and sometimes they occur on Passover. It’s rare that they pop up on tetrad cycles, yes, but it’s at best a mathematical curiosity that is a result of our attempt to keep our various calendrical systems in sync with the heavens.  It’s interesting to check out the tally of total eclipses versus tetrads over a two millennium span:

Century Number of Total Lunar Eclipses Number of Tetrads Century Number of Total Lunar Eclipses Number of Tetrads
11th

62

0

21st

85

8

12th

59

0

22nd

69

4

13th

60

0

23rd

61

0

14th

77

6

24th

60

0

15th

83

4

25th

69

4

16th

77

6

26th

87

8

17th

61

0

27th

79

7

18th

60

0

28th

64

0

19th

62

0

29th

57

0

20th

81

5

30th

63

1

 

Note that over a five millennium span from 1999 BC to 3000 AD, the max number of eclipse tetrads that any century can have is 8, which occurs this century and last happened in the 9th century AD.

Of course, the visual appearance of a “Blood of the Moon” that’s possibly alluded to in Revelation is a real phenomena that you can see next week from North and South America as the Moon enters into the dark umbra or core of the shadow of the Earth. But this occurs during every total lunar eclipse, and the redness of the Moon is simply due to the scattering of sunlight through the Earth’s atmosphere. Incidentally, this redness can vary considerably due to the amount of dust, ash, and particulate aerosols aloft in the Earth’s atmosphere, resulting in anything from a bright cherry red eclipse during totality to an eclipsed Moon almost disappearing from view altogether… but it’s well understood by science and not at all supernatural.

The changing colors of a lunar eclipse: a mosaic of four eclipses. Photos by author.
The changing colors of a lunar eclipse: a mosaic of four eclipses. Photos by author.

Curiously, the Revelation passage could be read to mean a total solar eclipse as well, though both can never happen on the same day.  Lunar and solar eclipses occur in pairs two weeks apart at Full and New Moon phases when the nodes of the Moon’s ecliptic crossing comes into alignment with the Sun — known as a syzygy, an ultimate triple word score in Scrabble, by the way — and this eclipse season sees a non-central annular eclipse following the April 15th eclipse on April 29th.

And yes, earthquakes, wars, disease, relationship breakups and lost car keys are on tap to occur in 2014 and 2015… just like during any other year. Lunar eclipses marked the fall of Constantinople in 1453 and the World Series victory of the Red Sox in 2004, but they’re far from rare. We humans love to see patterns, and sometimes this habit works against us, making us see them where none exists. This is simply a case of the gambler’s fallacy, counting the hits at the cost of the misses. We could just as easily make a case that the upcoming eclipse tetrad of April 15th, October 8th, April 4th and September 28th marks US Tax Day, Croatian Independence Day, The Feast of Benedict of the Moor & — Michael Scott take note — International World Rabies Day… perhaps the final 2015 eclipse should be known as a “Rabies Moon?”

So, what’s the harm in believing in a little gloom and doom? The harm in believing the world ends tomorrow comes when we fail to plan for still being here the day after. The harm comes when something like the Heavens Gate mass suicide goes down. We are indeed linked to the universe, but not in the mundane and trivial way that astrologers and doomsdayers would have you believe. Science shows us where we came from and where we might be headed.  We’ve already fielded queries from folks asking if it’s safe (!) to stare at the Blood Moon during the eclipse, and the answer is yes… don’t give in to superstition and miss out on this spectacular show of nature because of some internet nonsense.

The upcoming lunar eclipse next week won’t mean the end of the world for anyone, except, perhaps, NASA’s LADEE spacecraft… be sure not to miss it!

 

Get Ready for the April 15, 2014 Total Lunar Eclipse: Our Complete Guide

 April the 15th: In the United States, it’s a date dreaded by many, as the date to file taxes – or beg for an extension – looms large. But this year, Tax Day gives lovers of the sky something to look forward to, as the first of four total lunar eclipses for 2014 and 2015 occurs on the night of April 14th/15th favoring North and South America.

The circumstances for the April 15th, 2105 eclipse.
The circumstances for the April 15th, 2014 eclipse. The top chart shows the path of the Moon through the umbra, and the bottom chart shows the visibility region (light to shaded areas) Click here for a technical description. Credit:  Eclipse Predictions by Fred Espenak, NASA/GSFC.

This marks the first total lunar eclipse visible from since December 10th 2011, which was visible at moonset from North America, and marks the start of the first of two eclipse seasons for 2014. Totality will last 1 hour, 17 minutes and 48 seconds, and will be visible in its entirety from the central Atlantic westward to eastern Australia. Unlike a total solar eclipse, which occurs along a narrow track, a total lunar eclipse can be viewed by the entire moonward facing hemisphere of the Earth.

Tracing the umbra: a mosaic of the December 2010 eclipse. Photos by author.
Tracing the umbra: a mosaic of the December 2010 eclipse. Photos by author.

The action begins at 4:37 Universal Time (UT)/12:37 AM EDT, when the Moon enters the western edge of the Earth’s shadow known as the penumbra. The Moon will be completely immersed in the penumbra by 5:58 UT/1:58 AM EDT, but don’t expect to see anything more than a faint tan shading that’s slightly darker on the Moon’s northeastern edge.

The real action begins moments later, as the Moon encounters the ragged edge of the umbra, or the inner core of the Earth’s shadow. When does the umbra first become apparent to you? Totality then begins at 7:06 UT/3:06 AM EDT and lasts until 8:24 UT/4:24 AM EDT, with mid-eclipse occurring just south of the center of the Earth’s shadow at 7:46 UT/3:46 AM EDT.

Finally, the eclipse ends as the Moon slides out of the penumbra at 10:37 UT/ 6:37 AM EDT.  Michael Zeiler (@EclipseMaps) has complied a fine video guide to the eclipse:

Field guide to the total lunar eclipse of April 14 – 15, 2014 from Michael Zeiler on Vimeo.

This eclipse is also notable for being part of a series of four lunar eclipses in 2014 & 2015, known as a “tetrad.” NASA eclipse expert Fred Espenak notes that this series of eclipses is also notable in that all four are visible in part or in their entirety from the United States. We’re in a cycle of 9 sets of tetrads for the 21st century, which began with the first set in 2003. Before that, you have to go all the way back to the 16th century for the last set of eclipse tetrads!

4AM EDT. Credit Starry Night Education software.
The position of the Moon within the Earth’s umbra on the morning of April 15th at 4AM EDT/8UT. Credit: Starry Night Education software.

For saros buffs, the April 15th eclipse is Member 56 of 75 of saros 122, which began on August 14th 1022 A.D. and runs out until a final penumbral eclipse of the series on October 29th, 2338. There are only two total eclipses left in this particular saros, one in 2032 and 2050. If you caught the total lunar eclipse of April 4th, 1996, you saw the last lunar eclipse in this same saros series.

Lunar eclipses have turned up at some curious junctures in history. For example, a lunar eclipse preceded the fall of Constantinople in 1453. A 2004 lunar eclipse also fell on the night that the Red Sox won the World Series after an 86 year losing streak, though of course, lunar eclipses kept on occurring during those losing years as well. Christopher Columbus was known to evoke an eclipse on occasion to get him and his crew out of a jam, and also attempted to use a lunar eclipse to gauge his position at sea using a method first described by Ptolemy while studying the lunar eclipse of September 20th, 331 B.C.

A handful of stars in the +8th to +12th magnitude range will be occulted by the eclipsed Moon as well. Brad Timerson of the International Occultation Timing Association (IOTA) has put together a list, along with graze line prospects across the United States. The brightest star to be occulted by the eclipsed Moon is +5th magnitude 76 Virginis across western South America and Hawaii:

Credit: Occult 4.0
The occultation footprint of 76 Virginis during the April 15th lunar eclipse. Credit: Occult 4.0

Note that the bright star Spica will be only just over a degree from the eclipsed Moon, and Mars will also be nearby, just a week past its 2014 opposition. And to top it off, Saturn is just one constellation to the east in Libra!

During the partial phases of the eclipse, watch for the Moon to take on a “Pacman-like” appearance. The Earth’s umbra is just under three times the size of the Moon, and the Greek astronomer Aristarchus of Samos used this fact and a little geometry to gauge the distance to our natural satellite in the 3rd century B.C.

As totality approaches, expect the innermost rim of the Moon to take on a ruddy hue. This is the famous “combination of all the sunrises and sunsets” currently underway worldwide as light is bent through the Earth’s atmosphere into its shadow. It’s happening every night, and during the totality of a lunar eclipse is the only chance that we get to see it.

4AM Credit: Stellarium
Looking to the southwest at 4 AM EDT from latitude 30 degrees north on the morning of April 15th. Credit: Stellarium.

You don’t need anything more sophisticated than the naked eye or “Mark 1 eyeball” to enjoy a lunar eclipse, though it’s fun to watch through binoculars or a low-power telescope field of view. One interesting project that has been ongoing is to conduct timings for the moment when the umbra contacts various craters on the Moon. It’s a curious mystery that the Earth’s shadow varies by a small (1%) but perceptible amount from one eclipse to the next, and efforts by amateur observers may go a long way towards solving this riddle.

Said color of the fully eclipsed Moon can vary considerably as well: the Danjon scale describes the appearance of the eclipsed Moon, from bright and coppery red (Danjon 4) to so dark as to almost be invisible (Danjon 0). This is a product of the amount of dust, volcanic ash and aerosols currently aloft in the Earth’s atmosphere.  During the lunar eclipse of December 9th, 1992 the Moon nearly disappeared all together, due largely to the eruption of Mount Pinatubo the year prior.

A lunar eclipse also presents a chance to nab what’s known as a Selenelion. This occurs when the Sun and the totally eclipsed Moon appear above the local horizon at the same time. This is possible mainly because the Earth’s shadow is larger than the Moon, allowing it to linger a bit inside the umbra after sunrise or before sunset. Gaining some altitude is key to making this unusual observation.  During the April 15th eclipse, selenelion sightings favor the Mid-Atlantic and Greenland where totality is underway at sunrise and eastern Australia, where the reverse is true at sunset.

Want to have a go at measuring the brightness or magnitude of the eclipsed Moon? Here’s a bizarre but fun way to do it: take a pair of binoculars and compare the pinpoint Moon during totality to the magnitude of a known star, such as Antares or Spica.

Note that to do this, you’ll first need to gauge the magnitude extinction of your particular binoculars: NASA’s got a table for that, or you could field test the method days prior on Venus, currently shining at a brilliant -4.2 in the dawn. Hey, what’s a $1,000 pair of image-stabilized binocs for?

And of course, weather prospects are the big question mark for the event. Mid-April weather for North America is notoriously fickle. We’ll be watching the Clear Sky Chart and Skippy Sky for prospects days before the eclipse.

Photography during an eclipse is fun and easy to do, and you’ll have the waxing gibbous Moon available to practice on days prior to event. Keep in mind, you’ll need to slow down those shutter speeds as the Moon enters into totality, we’re talking going down from 1/60th of a second down to ¼” pretty quickly. In the event of a truly dark eclipse, the Moon may vanish in the view finder all together. Don’t be afraid to step exposures up to the 1 to 4 second range in this instance, as you’ve got over an hour to experiment.

Photo by author
Our “eclipse hunting rig…” the DSLR is piggy-backed to shoot stills on the main scope, which will shoot video. Note that the “f/34 field stop” will most likely be removed!  Photo by author

Thus far, only one webcast for the eclipse has surfaced, courtesy of the venerable Slooh. We’ll most likely be doing a follow up roundup of eclipse webcasts as they present themselves, as well as a look at prospects for things like a transit of the ISS in front of the eclipsed Moon and weather forecasts closer to show time.

And speaking of spacecraft, China’s Chang’e 3 lander and Yutu rover will have a fine view of a solar eclipse overhead from their Mare Imbrium vantage point, as will NASA’s LRO and LADEE orbiters overhead. In fact, NASA hinted last year that the April 15th eclipse might spell the end of LADEE entirely…

And thus marks the start of eclipse season one of two for 2014. Next up will be a curious non-central annular solar eclipse over Antarctica on April 29th, followed by another total lunar eclipse on October 8th, and a fourth and final partial solar eclipse of the year for North America of October 23rd.

Watch this space and follow us on Twitter as @Astroguyz, as we’ll be “all eclipses, all the time,” for April… no new taxes guaranteed!

Next up: Heard the one about the Blood Moon? Yeah, us too… join us as we debunk the latest lunacy surrounding the eclipse tetrad!

–      Got pics of the lunar eclipse? Send ‘em in to Universe Today, as a post-eclipse photo round up is a very real possibility!