Going to have a 'blue moon'
Astronomy lovers should circle 31/8 on the desk calendar, because that is the day they will have the opportunity to admire the "blue moon" the first time in nearly three years.
 The moon does not emit blue light when it's the 2nd round of the month. Photo: thelensflare.com
The phenomenon of "blue moon" took place at 13h58 GMT on 31/8 (20h58 GMT), Space said. This is the second full moon in August. Previous full moon was on 1/8. After 31/8, we will have to wait until July / 2015 to see the "blue moon".
"Blue Moon" (blue moon) is the English term that people used to call the phenomenon of a full moon twice in a month. But the moon does not emit blue light when it rounded the second time in a month. Some materials recorded blue moon in 1980 and 1991 due to air pollution (dust particles scatter blue light that we see the blue moon).
"Blue moon" exist by the months in the calendar does not coincide with the month according to the lunar cycle. Usually every year there are 12 full moons corresponds to 12 months. But because the moon orbits the earth in 29.5 days, the months in the calendar should be 30 or 31 days per calendar year with more than 11 days compared to the lunar year. So after about 2-3 years there will be a lunar year of 13 months, which corresponds to 13 times full moon.
Minh Long |
