The earlier darkest lunar eclipse was observed on August 6, 1971 and the next one would be 47 years from now on, on June 6, 2058.
Other than the near perfect alignment of these solar system bodies, atmosphere plays its role too to make the eclipsed moon really very dark. This eclipse of June 15 is likely to be one of the darkest ones due to the ashes thrown in the earth's atmosphere by the recent eruption of Iceland's most active volcano, Grimsvotn.
On the night of June 15 more than half the world will have the opportunity to watch one of the darkest Lunar eclipses. People living in eastern Africa, the Middle East, central Asia and western Australia will have opportunity to witness the entire eclipse, from beginning to end. At mid-eclipse, the moon will be overhead at Mauritius.
A lunar eclipse takes place when the moon enters the shadow of the earth. On this night the earth is directly between the moon and the sun, blocking the sunlight reaching the moon. On this night the moon and the sun are on opposite sides of the earth. The moon will in the penumbral shadow of the earth at about 22:53.
Nothing much will be noticeable to the untrained eyes for next 30 to 40 minutes. After that one might notice a gradual change in the brightness on the lunar disk. By 23:53 the moon will be in the umbra of the earth's shadow.
The dark shadow will progress on the lunar disk. This will be quite noticeable to the naked eyes.
The eclipse will begin at 22.53 and end at 04:32. During the lunar eclipse, the moon will be completely covered by earth's shadow from 23:53 on June 15 to 03:32 on June 16. It will be the first of the two total lunar eclipses in 2011, the second occurring on December 10. Earlier on January 4, a partial lunar eclipse was seen.
