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May 10th, 2013 Annular Solar Eclipse

CAUTION! OBSERVING A SUN ECLIPSE IS DANGEROUS AND MAY CAUSE IRREVERSIBLE EYE DAMAGE, UP TO BLINDNESS, ANNULAR AND PARTIAL ECLIPSES INCLUDED! Observing a Sun eclipse necessitates DEDICATED SAFE TECHNIQUES!

That first solar eclipse in 2013 -and that year's second major astronomical event- is a annular eclipse occurring on May 10th, 2013. A annular eclipse is occurring when the apparent diameter of the Moon is smaller than the one of the Sun, due to the general geometry of the eclipse. A ring of Sun is still visible, surrounding the dark disk of the Moon, as it doesn't provide the observers with the more classical view of the Sun totally hidden and of the corona streaming away. for more about the solar eclipses, theoretically, see our tutorial 'Sun Eclipses'. The eclipse occurs when the Sun is lying in eastern Ares. With a 106 to 150 mile (171 to 225km)-wide track, the annular eclipse is seen from western Australia into far in the Pacific Ocean. Australia, eastern Papua New Guinea, the Solomon Islands, and the Gilbert Islands are concerned. Like usual, a partial eclipse is seen on a wide area either side of the line of centrality, stretching all over the Pacific (with most of the islands there concerned) and Indonesia and Australia. The closer the line of the eclipse, the more the indented Sun! A relatively wide path of annularity is due to that Moon will reach apogee -its farthest Earth- just 3 ½ days later. The annular ring, on a other hand, is consequently quite thick because the Moon appears only 95 percent the diameter of the Sun

Eclipse's main data are the following (data as of October 2012, F. Espenak, NASA's GSFC). The Moon's apparent diameter will be of 29' 47.6", compared to the Sun's 30' 40.8". Greatest eclipse occurs over the open ocean at 00:25:12.9 UT with the duration of annularity 6 minutes and 3 seconds at that time and the the Sun at 74 degree above the horizon. for more about how to observe a solar eclipse, see our tutorial 'Observing a Sun Eclipse':
- greatest eclipse: 00:25:12.9 UT
- eclipse magnitude (fraction of the Sun's diameter obscured by the Moon at greatest eclipse): 0.9544
- U1 to U4 (moments of first-last external-internal tangency of the antumbra with Earth's limb; practically these are the moments of the eclipse for the places where the eclipse is annular); in UT: U1 at 22:30:33.9, U2 at 22:34:46.4, U3 at 02:15:42.1, U4 at 02:19:58.3
- P1 to P4 (moments of first-last external-internal tangency of the penumbra with Earth's limb; practically these are the moments of the eclipse for the places where the eclipse is partial), in UT: P1 at 21:25:09.7, P2 at 23:45:19.4, P3 at 01:05:14.8, P4 at 03:25:23.0

see a .PDF map for the May 10th, 2013 annular solar eclipse. map courtesy Fred Espenak - NASA/GSFC

. for more about this eclipse and for more about solar and lunar eclipses generally, you may see at Fred Espenak's NASA's eclipse website