In 2019, skywatchers in a few select locations on Earth will have three opportunities to see a solar eclipse, a celestial event in which the moon briefly appears to take a bite out of the sun.
A solar eclipse occurs when the disk of the moon appears to cross in front of the disk of the sun. A total solar eclipse — like the one that crossed the U.S. on Aug. 21, 2017 — occurs when the disk of the moon blocks 100 percent of the solar disk. A partial eclipse occurs when the moon covers only part of the sun. If the moon passes directly in front of the sun when it is near apogee, the point in its elliptical orbit where it is farthest from Earth, skywatchers will see an annular eclipse, also known as a "ring of fire."
On Jan. 5-6, 2019, a partial eclipse was visible from northeast Asia and the north Pacific. A total solar eclipse will follow on July 2, and it will be visible almost exclusively over South America. Last but not least, an annular solar eclipse will occur over Saudi Arabia, India and southeast Asia on Dec. 26, and it will appear as a partial eclipse over Asia and Australia. You can see a complete list of the upcoming solar eclipses on NASA's website, which provides information about solar eclipses, including detailed maps of each eclipse path. [Solar Eclipses: An Observer's Guide (Infographic)]
The only total solar eclipse of 2019
Nearly two years after the Great American Solar Eclipse of 2017, the world will once again have a chance to experience totality, when the moon completely blocks the sun, turning day into night as its 125-mile-wide (200 kilometers) shadow moves across the surface of the Earth.
On July 2, 2019, the moon will block the sun over the South Pacific Ocean, Chile and Argentina. Other parts of South America will be able to see a partial eclipse. Most of this eclipse will be happening over the Pacific Ocean, where the partial eclipse starts at 12:55 p.m. EDT (1655 GMT).
This total solar eclipse will have a longer duration than last year's total solar eclipse, with totality lasting up to 4 minutes and 33 seconds. However, this maximum duration may be visible only to observers on a few boats and airplanes, because it will be happening over the Pacific Ocean.
A map of the total solar eclipse on July 2, 2019.
Totality will first make landfall over Oeno Island, a British territory in the South Pacific Ocean, at 10:24 a.m. local time (1824 GMT). It will reach the coast of Chile near the city of La Serena at 4:39 p.m. local time (1939 GMT). Moving southeast, the moon's shadow will cross the Andes mountains and graze San Juan, Argentina, which lies just inside the path of totality. It will barely miss Cordoba and Buenos Aires, Argentina, as well as Montevideo, Uruguay, passing just south of these three cities before heading back out to the Atlantic Ocean just before sunset at 5:40 p.m. local time (2040 GMT).
The tables below show the start, peak and end times of the eclipse for a few cities in and around the path of totality, as well as the maximum obscuration, or the percentage of the sun's disk that will be covered by the moon. (All times are given in local time zones.)
You can also look up the details for any location using this interactive map by timeanddate.com.
'Ring of fire' annular eclipse coming Dec. 26
The third and final solar eclipse of the year will be a "ring of fire" eclipse on Dec. 26, and it will be visible from Saudi Arabia, Qatar, India, Sumatra, Borneo, Guam and the Philippines. Skywatchers in other parts of Asia, Australia and Africa will be able to see a partial eclipse.
During this eclipse, the moon will cross directly in front of the sun. However, because the eclipse occurs just a few days after the moon reaches apogee — its farthest distance from Earth — its apparent size in the sky will be smaller than the sun. This means that it won't block the sun entirely, but it will instead turn the sun into a blazing "ring of fire" from Earth's perspective.
A map of the annular solar eclipse on Dec. 26, 2019
The first location to see the annular eclipse is 137 miles (220 km) northeast of Riyadh, Saudi Arabia, according to Espenak's website EclipseWise.com. It will begin there at 6:34 a.m. local time (3:34 GMT), and it will last 2 minutes and 59 seconds. Guam will be the last place on Earth to see the eclipse. The island will see the annular eclipse last for more than 3 minutes, and the sun will set before the partial phase of the eclipse has ended.
You can look up visibility information for any location using this interactive map by timeanddate.com or Espenak's eclipse circumstances calculator.
How to view the sun safely
WARNING: Looking directly at the sun, even during an annular eclipse, can lead to blindness and other forms of permanent eye damage if you aren't wearing proper eye protection.
To safely observe the sun or watch an eclipse, you need special protective eyewear or eclipse glasses. Basic sunglasses, even those with UV protection, will not sufficiently protect your eyes. If you're planning to document the eclipse with any photo equipment, there are special solar filters you can add to make sure the remaining ring of sunlight doesn't take a toll on your vision.
The safest way to observe an eclipse is indirectly, using a pinhole camera that you can make easily at home.
If you must document one of these events, a simple, wide-angle snap should capture the moment, even if you're using your smartphone camera.
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