Totality from central Indiana. Credit: Peter Forister.
The last total solar eclipse across the Mexico, the U.S. and Canada for a generation wows observers.
Did you see it? Last week’s total solar eclipse did not disappoint, as viewers from the Pacific coast of Mexico, across the U.S. from Texas to Maine and through the Canadian Maritime provinces were treated to an unforgettable show. The weather threw us all a curve-ball one week out, as favored sites in Texas and Mexico fought to see the event through broken clouds, while areas along the northeastern track from New Hampshire and Maine onward were actually treated to clear skies.
Totality! As seen from Madras, Oregon, during the 2017 total solar eclipse. Credit: NASA/Aubrey Gemignani
Totality and the April 8th total solar eclipse offers a rare chance to study the Sun.
We’re less than three weeks out now, until the April 8th total solar eclipse crosses North America. And while over 31 million residents live in the path of totality, many more will make the journey to briefly stand in the shadow of the Moon. Several scientific projects are also underway to take advantage of the event.
Europe, the Middle East, and northeast Africa will see the final partial solar eclipse of 2022 next Tuesday.
When it comes to eclipses, a close shave is better than nothing at all. Just such event happens this coming Tuesday on October 25th when the outer shadow of the Moon grazes the northern hemisphere of the Earth, resulting in a fine partial solar eclipse for Europe and surrounding regions.
The first total lunar eclipse of 2021 occurs early next week and features the largest Full Moon of the year.
Ready for the lunar eclipse drought to come to an end? It’s been a while since we’ve watched the Moon pass through the Earth’s dark inner shadow, to be sure. 2020 featured four lunar eclipses… all of which were faint penumbrals. In fact, you have to go all the waaaaay back to January 21st, 2019 (remember 2019?) to remember the last total lunar eclipse. But that wait ends next Wednesday morning on May 26th, with a very short total lunar eclipse, centered on the Pacific region.
The Full Moon rises in partial eclipse over the sandstone formations of Writing-on-Stone Provincial Park in southern Alberta, on the evening of September 27, 2015.
Happen to be in Europe, Africa, Asia or Australia on Tuesday night, July 16th with clear skies? If the July weather cooperates, you’ll have a good view of a fine partial lunar eclipse, the final lunar eclipse for 2019.
A mosiac of partial and total phases for Sunday night's eclipse, showing the size and curved outline of the Earth's shadow. Image credit and copyright: Alan Dyer.
Wow. Sunday night’s total lunar eclipse offered an amazing view, and for a few astute observers, a little surprise.
The Moon just a few minutes from the end of totality on October 8th. 2014. Credit and Copyright: Alan Dyer.
By now, you’ve heard the news. One of the top astronomy events for 2019 is coming right up on the night of January 20th into the morning of the 21st with a total eclipse of the Moon. There’s lots of hype circulating around this one, as it assumes the meme of the “SuperBloodWolf Moon eclipse” ’round ye ole web.
The partial lunar eclipse of June 4th, 2012. Credit: Dave Dickinson
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.
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!
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.
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.
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.
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.
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.
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.
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!
-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.
The November 2012 total solar eclipse as seen from Australia. Image credit and copyright: Alan Dyer.
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.
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.
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.
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.
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.
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.
