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Rare solar eclipse in America, Europe and Africa
A rare solar eclipse allowing a view of the Sun that is totally or partially blocked by the Moon has taken place. It was first visible in the southern United States, before sweeping east across the Atlantic Ocean and the African continent.
The US space agency, Nasa, said the greatest total eclipse occurred over the Atlantic Ocean.
One of the best views was in northern Kenya, where tour companies organised trips to view a total blackout.
Local myths there attribute the event to the Moon eating the Sun.
Men and women from the Turkana tribe in Kenya took part in a ceremony ahead of the eclipse
Partial views were available in eastern North America and southern Europe.Halo This solar eclipse was a rare occurrence in that it was "hybrid" - switching between an annular and total eclipse.
In a total eclipse, the Moon completely covers the sun, while an annular eclipse occurs when the Moon is at its farthest from the Earth and does not block out the Sun completely, leaving a halo of sunlight still visible around the Moon.
The eclipse event began about 1,000km (620 miles) east of Jacksonville, Florida with an annular eclipse visible for four seconds at sunrise.
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Eclipse safety
- Looking directly at the sun during a partial or annular eclipse, or the partial phases of a total solar eclipse, can can cause temporary or permanent damage to the retina
- Special welder's glasses or mylar lenses manufactured especially for viewing solar eclipses are recommended
- Or you can make a pinhole camera by making a 3mm hole in a sheet of paper, turning your back to the Sun and using the pierced page to project the image of the Sun on to another sheet of paper
As the Moon's shadow raced east the eclipse switched from annular to total along a narrow corridor.
The greatest total eclipse occurred in the Atlantic Ocean,
approximately 330km south-west of Liberia, and lasted for more than one
minute.The eclipse continued across Africa through the Congos until it passed through northern Uganda and northern Kenya, ending in southern Ethiopia and Somalia.
Either side, a partial eclipse was seen within a much broader path including eastern North America, northern South America, southern Europe, the Middle East and Africa.
Experts warned that no-one should attempt to view the Sun with the naked eye.
A safe view of eclipses can be obtained by using special welder's glasses or a pinhole camera.
An annular eclipse is when the Moon is
too far away to cover the Sun completely, and retains a fiery halo -
such as here in Portugal in 2005
Eclipse types
A solar eclipse occurs when the Moon comes between the Sun and the observer. This happens when the shadow cone of the Moon intersects the surface of the Earth, and is observable by anyone within this shadow zone.
Two conditions have to be met for a solar eclipse to occur. The first concerns the relationship between the orbits of Earth and the Moon, which are not in the same plane, but are inclined at around 5 degrees (5 degrees 8' 43") to each other. The Moon crosses the plane of Earth's orbit twice in each complete orbit. For an eclipse to occur the Moon must be near one of these intersection points (or nodes).
The second condition is that the Sun, Earth and the Moon must also be lined up, corresponding to the phase of the New Moon.
Why the eclipse goes west to east
The most favourable conditions for a total eclipse are when the Moon is at its perigee, Earth is farthest from the Sun (around July) and when the Sun is observed near zenith. When these conditions are all met, one can have a totality duration of more than seven minutes.
Total lunar eclipse
Earth's umbra is larger than the whole Moon. So, one will observe either a total eclipse by the umbra (which can be well observed), a partial eclipse by the umbra and penumbra, or a total or partial eclipse by the penumbra only. The duration of a lunar eclipse is much longer than a solar eclipse, and can take as much as six hours.
In practice, the lunar eclipse conditions are modified due to the refraction of the Sun's rays by Earth's atmosphere. This refraction (of 35 minutes of arc) allows some light to penetrate the cone of geometric umbra. So even during total lunar eclipse, the lunar disk is not completely dark. This grazing light is more absorbed by Earth's atmosphere in the blue and yellow portions of the spectrum, giving a particular reddish light during total lunar eclipse.
Watch for Sunday's strange solar eclipse on East Coast — and online
Nov. 1, 2013 at 12:51 PM ET
Aaron Favila / AP file
A partial solar eclipse shines in the skies over Manila Bay in the
Philippines in January 2009. Observers on the U.S. East Coast could see
something like this if they have a clear view to the eastern horizon at
sunrise on Sunday. A total eclipse could be seen along a narrow strip of
the planet passing over the Atlantic and Africa.
And no matter where you are, you'll want to be watching the Web as well — so you can catch the show when it's totally at its best.
Sunday's eclipse is a strange one, known as a hybrid. Millions of observers on the eastern edge of the America, in southern Europe and nearly all of Africa have the potential to see a partial eclipse. Over a narrow strip of the western Atlantic, there'll be an annular eclipse, with a tiny portion of the sun's disk remaining visible as a "ring of fire." But as time goes on, the eclipse will turn total: Skywatchers along a thin band of African territory, stretching from Gabon to Somalia, could see a completely blacked-out sun.
Only 5 percent of all eclipses are annular-total hybrids. The most recent one occurred back in 2005. All solar eclipses involve the moon getting right in front of the sun and casting its shadow on our planet. But here's why Sunday's hybrid eclipse is special: During the course of the day, the moon's distance from the spot where its shadow falls on Earth changes just enough to make the transition from leaving some of the sun exposed, to covering up the entire disk.
For detailed information about the eclipse's track, check out Eclipse-maps.com, NASA's eclipse website and this interactive eclipse map from Xavier Jubier.
Fred Espenak / Sky & Telescope
The partial phase of Sunday's solar eclipse can be seen over a wide
swath of the world, but the annular-total phase is visible only along a
narrow track. The eclipse begins as a "ring of fire" annular event, but
turns total by the time the moon's shadow reaches the African coast.
You can buy special eclipse-viewing filters at planetariums or science centers. You can look through No. 14 welding glass. You can make a "pinhole camera," hold out a colander or knit your fingers together to create projected images of the crescent sun. You can hook up with a local astronomy club that has the proper viewing gear. But trying to see a partial solar eclipse with unprotected eyes will just lead to vision problems.
Technically speaking, the partial eclipse could be visible as far inland as, say, Tennessee. Sky & Telescope projects that 57 percent of the sun's diameter could be covered over at sunrise in Boston, 48 percent in New York, 44 percent in Philadelphia, 35 percent in Washington, and 36 percent in Miami. But you'd have to have a clear view of a flat horizon — and no matter where you are on the East Coast, the partial eclipse will be over within an hour after sunrise. (Use this TimeandDate.com calculator to find out when the sun rises in your locale, and remember that daylight saving time ends on Saturday night.)
Watching it online
All these issues about logistics and safety go away if you're watching the eclipse online. And unless you're in Africa, the only way you'll see totality in real time is via the Web.
Totality is well worth witnessing: When the sun's disk is fully covered, the delicate outer solar atmosphere — known as the corona — can be seen gleaming against the black sky. The total phase will be relatively short on Sunday, lasting somewhere between a second and a minute or so.
David Dickinson of Astroguyz.com previews Sunday's solar eclipse.
“This will be the most difficult eclipse we’ve covered at Slooh over the years," Cox said in a news release. "Our expedition will be made in a series of 4x4 vehicles carrying our delicate observation equipment across some of the harshest terrain in Africa. After three days across country, we’ll be setting up camp near the home of the largest population of crocodiles in the world — Lake Turkana."
Slooh's show will feature commentary from Cox as well as astronomer Bob Berman, documentary filmmaker Duncan Copp and other guests. Viewers can email questions in advance to coxy@slooh.com, or tweet questions to the panel during the broadcast using the Twitter hashtag #solareclipse. The eclipse should reach totality at Lake Turkana around 9:25 a.m. ET.
Watch Slooh's eclipse coverage on Sunday.
More TV coverage may be available via Gabonese television, Kenya's KTN or other African outlets. And after the eclipse is over, there should be lots of great images to see on SpaceWeather.com. Did you snap a picture? Share it with us via the NBC News Facebook page or tweet it with the hashtag #NBCeclipse.
More about solar eclipses:
- Flash interactive: How a solar eclipse happens
- Spectacles donated for Africa's eclipse spectators
- Slideshow: Greatest hits from solar eclipses
- America's 2017 total eclipse already sparks interest
- NBC News archive on eclipses
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