If the clouds can keep clear, a solar eclipse will reveal itself to several million people in parts of Indonesia and on the Indian and Pacific Oceans on March 8 and 9.
Palembang in Sumatra will be the first major city to see the total solar eclipse – the moment that the moon orbits in front of the sun, completely blocking it and casting a long, dark shadow over Earth – at about 7:20 a.m. local time.
Astronomy enthusiasts around the globe can watch the spectacle online beginning at 6 p.m. Eastern time on Tuesday, thanks to a live stream hosted by Slooh Community Observatory.
The sun will be entirely obscured by the moon for 90 seconds to 4 minutes, depending on where the observer is. It will last the longest in the Pacific Ocean, east of the Philippines. On land, it will be visible for 1 to 3 minutes. There is a high chance that clouds over Indonesia will interfere with viewing there, as the nation is in its wet season.
Though the moon passes between the Earth and the sun every month, a total solar eclipse happens only when the three are aligned, which causes the moon to block out the sun, leaving only a faint halo of rays visible, known as the corona. This week’s eclipse is happening while the moon is at its closest point to Earth – called perigee – an effect of its elliptical orbit around Earth. The closer moon will appear larger from Earth, a phenomenon known as a supermoon.
The last total solar eclipse was in March 2015; with its peak over Norway's Svalbard islands near the North Pole. The last one before that was in November 2012.
This week’s total solar eclipse will be visible along a 100 to 150 kilometer (62 to 93 mile) -wide path that will begin in the Indian Ocean and move across parts of Indonesia, including Sumatra, Kalimantan, and Sulawesi. It will end in the the northern Pacific Ocean, disappearing near Hawaii.
People in South Asia, East Asia, and the north and east of Australia may be able to catch a partial eclipse, when only part of the sun is covered by the moon. Others can watch it online.
Scientists and eclipse chasers who have traveled from around the world to catch the rare sight are getting ready for the big occasion. International tour agencies have organized land tours for photographers and ocean charters for groups who want to view the eclipse from sea. A former NASA scientist is leading a group of eager observers from Canada, the United States, Britain, China, and Iran aboard the Holland America Line cruise ship, says Oklahoma-based Spears Travel.
Palu, a city on the Indonesian island Sulawesi, has planned an eclipse festival, and 10 other cities have promoted themselves as total eclipse destinations.
During the total eclipse, it is safe to look at the sun with the naked eye. Though during the partial eclipse phases, it is dangerous to do so, particularly through a telescope. Viewers should use specially designed filters for their binoculars or telescopes, says University of Waterloo optometrist and eclipse chaser B. Ralph Chou, ones that are coated with a fine layer of aluminum, chromium, or silver. These would include the darkest welder's glass and filters made of aluminized polyester in the darkest shades.
This report contains material from The Associate Press.