Upcoming June 16, 2011 Indonesia will have the longest total lunar eclipse this year."Total Lunar eclipse will be happening around 1.5 hours," said Thomas Djamaluddin, a research professor of astronomy and astrophysics from the Institute of Aviation and Space Agency to VIVAnews via telephone, Tuesday, June 7, 2011.The total duration of the eclipse, the partial lunar eclipse early start to the end, Djamal said, is expected to last for 3 hours, 20 minutes, from 1:22 o'clock pm - 5:02 pm. The duration of it, Djamal added, longer than the total lunar eclipse which will occur on December 10, 2011.Compared with December lunar eclipse, this eclipse of May 16 also have greater opportunities to be enjoyed with the naked eye, given the current entering the dry season. "Eclipse in December was relatively more difficult to predict, because it was in the rainy season," he said.Djamal also revealed, this opportunity for people to know the quality of the upper atmosphere (the stratosphere at an altitude above 5,000 meters from the surface of the earth) that may have been 'contaminated' by the accumulation of volcanic dust.
The reason is, volcanic dust that reaches the upper atmosphere, can last for years. For example, the Mount Pinatubo eruption which occurred in 1991 and took hundreds of casualties, dust vulkaniknya last up to two years.
According to Knopf, the quality of the atmosphere that can be measured by looking at the brightness of the color line between the shadow of the earth with the light of the moon. When the color of light the moon looks bright and firm, then the quality of the atmosphere is better. But if the color is darker, the worse the quality of the atmosphere.
Djamal Letting, after the eruption of Mount Tambora in 1815 which killed about 100 thousand inhabitants, the earth's atmospheric layers of volcanic ash when it was closed until some time so when a lunar eclipse, the line between the shadow of the earth with the light of the moon dark and diffuse.