First 2013 Solar Eclipse Is Annular Solar Eclipse Friday, May 10

Summary: The first 2013 solar eclipse is an annular solar eclipse Friday, May 10, that favors the Pacific Ocean, especially in the Southern Hemisphere.

Earth visibility chart and eclipse statistics for annular solar eclipse of May 10, 2013: "Permission is freely granted to reproduce this data when accompanied by an acknowledgment, Eclipse Predictions by Fred Espenak, NASA GSFC Emeritus," via NASA Eclipse Web Site

The first 2013 solar eclipse is an annular solar eclipse Friday, May 10, with a 171 to 225 kilometer-wide (106.254 to 139.809 mile-wide) path favoring the Southern Hemisphere, especially Australia and the South Pacific Ocean, but also including low latitudes of the North Pacific Ocean.

On the NASA Eclipse Web Site, retired astrophysicist Fred Espenak, known as “Mr. Eclipse,” explains that the wide path of annularity reflects the moon’s nearness to monthly apogee, the farthest center-to-center distance between Earth and moon during the monthly lunar orbit. Apogee takes place 3.5 days later, on Monday, May 13, at 13:32 Universal Time. May’s apogee measures a distance of 405,827 kilometers (252,169.207 miles).

The great distance between Earth and moon is responsible for the moon’s incomplete coverage of the sun’s image, from Earth’s perspective. The extension of the solar limbs beyond the lunar overlay forms an annulus (Latin: “little ring”).

The path of annularity follows the sweep of the moon’s antumbral shadow across Earth’s surface. The antumbra (Latin: ante “before” + umbra “shadow”) extends beyond the umbra, which constitutes the shadow’s darkest, innermost region.

The path of annularity begins Thursday, May 9, at 22:30:33.9 UT (Friday, May 10, at 6:30 a.m. AWST Australian Western Standard Time) near Collier Range National Park in northern Western Australia. With the sun clinging to the horizon, recommended observation sites are high points or unobstructed areas with free sights to the east-northeast.

“Mr. Eclipse” notes increases in the central line duration of annularity during the eastward travels of the moon’s antumbral shadow. The central line tracks the path of the lunar shadow cone’s central axis across Earth’s surface. Annularity lasts longest on the central line and diminishes to zero at the limits of the path of annularity.

East of Collier Range National Park in the neighboring Northern Territory, Tennant Creek observes an annular phase of 3 minutes 4 seconds, beginning Thursday, May 9, at 22:35 UT (Friday, May 10, at 8:05 a.m. ACST - Australian Central Standard Time). The sun has an altitude of 15.4 degrees at the start of annularity and rises to 16 degrees by the phase’s end.

“Mr. Eclipse” reports that the antumbra leaves Australia at Rinyirru (Lakefield) National Park (CYPAL Cape York Aboriginal Land) in Far North Queensland. At Rinyirru, annularity ends Thursday, May 9, at 22:48 UT (Friday, May 10, at 8:48 a.m. AEST - Australian Eastern Standard Time). The sun’s altitude measures 28.1 degrees at the phase’s start and 28.8 degree at the end.

The next landfall is eastern Basilaki Island in Papua New Guinea’s Louisiade Archipelago. Annularity lasts 4 minutes 59 seconds. The sun’s altitude rises from 38.4 degrees at the start to 39.4 degrees at the end of annularity. According to Time And Date website, the antumbra exits Basilaki Island Thursday, May 9, at 23:02 UT (Friday, May 10, at 9:02 a.m. PGT - Papua New Guinea Time).

With a velocity of 0.98 kilometers per second (0.608 miles per second), the moon’s antumbra heads northeast across the Solomon Sea to make a last major landfall. Choiseul Island, known natively as Lauru, enjoys an annularity of 5 minutes 16 seconds. According to Time And Date web site, Choiseul Island’s annularity occurs Thursday, May 9, between 23:12 and 23:17 UT (Friday, May 10, between 10:12 a.m. and 10:17 a.m. SBT - Solomon Islands Time). The sun has a starting altitude of 48.3 degrees and an ending altitude of 49.2 degrees.

After Choiseul Island, the lunar antumbra encounters the South Pacific Ocean. The antumbra’s northeasterly trek crosses the equator to make contact with the North Pacific Ocean for annularity’s major event.

Greatest eclipse occurs Friday, May 10, at 00:25:12.9 UT over open ocean. Greatest eclipse represents the instant of the axis of the lunar shadow cone’s closest passage to Earth's center. At greatest eclipse, the duration of annularity is 6 minutes 3 seconds. The path’s width is 172.6 kilometers (107.248 miles). The sun’s altitude marks 74.4 degrees above the open North Pacific Ocean’s flat horizon.

After the center line reaches the fourth parallel north, the antumbra curves to the southeast, heading toward the equator and the North Pacific Ocean. Annularity ends with the antumbral exit from Earth’s surface over open ocean Friday, May 10, at 02:19:58 UT. U3 is the astronomical designation for the instant of the antumbral shadow’s last contact with Earth’s surface.

A partial solar eclipse frames the annular solar eclipse. The partial solar eclipse begins Thursday, May 9, at 21:25:09.7 UT. The partial solar eclipse ends Friday, May 10, at 03:25:23.0 UT.

The path of partiality is wider than that of annularity. Partiality brings Indonesia and the entire island of New Guinea into the path of visibility.

The May 2013 annular solar eclipse belongs to Saros series 138. A Saros cycle assigns eclipses to families, known as series. A Saros cycle lasts for approximately  6,585.3 days (18 years 11 days 8 hours).

Observers of the annular and partial phases of May 2013’s solar eclipse should not look directly at the sun. Safe viewing of May 2012’s solar eclipse calls for use of proper equipment and following of proper techniques.

The takeaway for the first 2013 solar eclipse, which occurs as an annular solar eclipse Friday, May 10, is the path of annularity’s primarily favoring the Southern Hemisphere, especially Australia and the South Pacific Ocean, but also crossing the equator to include low latitudes of the North Pacific Ocean.

animation showing annular solar eclipse of May 10, 2013: A.T. Sinclair/NASA Eclipse Web Site, Public Domain, via Wikimedia Commons

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Earth visibility chart and eclipse data for annular solar eclipse of May 10, 2013: "Permission is freely granted to reproduce this data when accompanied by an acknowledgment, Eclipse Predictions by Fred Espenak, NASA GSFC Emeritus," via NASA Eclipse Web Site @ https://eclipse.gsfc.nasa.gov/OH/OHfigures/OH2013-Fig02.pdf

animation showing annular solar eclipse of May 10, 2013: A.T. Sinclair/NASA Eclipse Web Site, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:SolarEclipse2013May10A.GIF

For further information:

Espenak, Fred. “Figure 2 Annular Solar Eclipse of 2013 May 10." NASA Eclipse Web Site > Solar Eclipses > Solar Eclipse Page > Solar Eclipses Past and Future: Eclipses During 2013 > Eclipses During 2013: 2013 May 10 Annular Solar Eclipse: Annular Solar Eclipse of May 10.
Available via NASA Eclipse Web Site @ https://eclipse.gsfc.nasa.gov/OH/OHfigures/OH2013-Fig02.pdf

Espenak, Fred. “Eclipses During 2013.” NASA Eclipse Web Site > Observer’s Handbook.
Available via NASA Eclipse Web Site @ https://eclipse.gsfc.nasa.gov/OH/OH2013.html

Espenak, Fred. “Five Millennium Catalog of Solar Eclipses: 2001 to 2100 (2001 CE to 2100 CE).” NASA Eclipse Web Site > Solar Eclipses.
Available via NASA Eclipse Web Site @ https://eclipse.gsfc.nasa.gov/SEcat5/SE2001-2100.html

Espenak, Fred. “Greatest Eclipse.” NASA Eclipse Web Site > Glossary of Solar Eclipse Terms.
Available via NASA Eclipse Web Site @ https://eclipse.gsfc.nasa.gov/SEhelp/SEglossary.html

Espenak, Fred. “Moon at Perigee and Apogee: 2001 to 2100 Greenwich Mean Time.” AstroPixels > Ephemeris > Moon.
Available via AstroPixels @ http://astropixels.com/ephemeris/moon/moonperap2001.html

Littmann, Mark; Ken Willcox; Fred Espenak. “Observing Solar Eclipses Safely.” MrEclipse > Totality.
Available @ http://www.mreclipse.com/Totality2/TotalityCh11.html

Marriner, Derdriu. “First 2012 Solar Eclipse Is Annular Solar Eclipse Sunday, May 20.” Earth and Space News. Wednesday, May 16, 2012.
Available @ https://earth-and-space-news.blogspot.com/2012/05/first-2012-solar-eclipse-is-annular.html

Marriner, Derdriu. "Friday, May 10, 2013, Annular Solar Eclipse Belongs to Saros Cycle 138." Earth and Space News. Wednesday, May 1, 2013.
Available @ https://earth-and-space-news.blogspot.com/2013/05/friday-may-10-2013-annular-solar.html

“May 9/10, 2013 -- Annular Solar Eclipse.” TimeAndDate > Sun & Moon > Eclipses.
Available @ https://www.timeanddate.com/eclipse/solar/2013-may-10

“May 9/10, 2013 -- Annular Solar Eclipse -- Collier Range National Park, Western Australia, Australia.” TimeAndDate > Sun & Moon > Eclipses.
Available @ https://www.timeanddate.com/eclipse/in/@8154248?iso=20130509