Second blue moon for 2010 due March 30 - Pagasa

Stargazers are in for a rare treat in March, as they will see the second blue moon for 2010, the Philippine Atmospheric Geophysical and Astronomical Services administration said. In Pagasa’s astronomical diary for March, Pagasa head Prisco Nilo said the blue moon - the occurrence of two full moons in one month - is due on March 1 and 30. “On the average, [a blue moon] takes place once every two and a half years. But the second blue moon for this year which will appear this March is an exceptional case. Since the full moon occurred on January 1 and 30, 2010 and preceded by 28 days of February, the event will be repeated on March 1 and 30, 2010. The next blue moon will be on August 2 and 31, 2012," Nilo said. Pagasa noted that since the moon takes 29.5 days to circle the Earth once in its orbit, it is possible that two full moons can occur within the same calendar month. Such was the case in January 2010, when the moon was full on the 1st and the 30th, making the full moon on the 30th a “blue moon." On the other hand, Nilo said the vernal equinox will occur on March 21, marking the beginning of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. At this time, it said the length of day and night in both hemispheres is equal on this day. Color blue on occasion Nilo added there have been times when the moon does seem to have a blue color. He said could be due to dust particles in the atmosphere, which scatter light. The effects of this dust on the light coming from the moon can cause it to appear bluish in color. He cited the eruption of the Krakatoa Volcano in 1883 that gave us one such “blue moon." “For about 24 months after this volcano erupted, the dust it spewed into the upper atmosphere which caused the moon to appear green and blue when viewed from around the world," he said. Venus, Mars visible Meanwhile, Nilo said Venus, the brightest naked eye planet, will be found low above the western horizon after sunset during the first week of the month. It will be shining at magnitude -3.9 and will be located among the background stars of the constellation Pisces, the Water Bearer. The brightest planet will be slowly moving upward each passing night. On the last week of the month, Venus, together with Mercury, will be found at about 13 and 10 degrees above the western horizon, 30 minutes after sunset, respectively. At around 7 p.m. of March 4, Mars will be found at about 56 degrees above the east northeastern horizon and will remain visible in the evening sky throughout the month. Its magnitude decreases from the beginning to the end of the month, ranging from -0.6 to +0.1 with a phase of 96 to 92 percent and a diameter from 12.04 to 9.31 arcseconds. During the first week of the month at around 9 p.m., Saturn will be shining at magnitude +0.6 and will be located at about 25 degrees from the eastern horizon. It will be found among the background stars of the constellation Virgo, the Virgin. By using a modest size telescope, it will reveal a diameter of 19.39 arc of a second and Saturnian satellites can sometimes be seen as tiny yellowish beads of light. “The inclination of its rings can be seen just 2 degrees from the observer’s line of sight, the smallest tilt this year," Nilo said. At around 5:30 a.m. of March 30, Uranus, Jupiter, and Neptune will be at 3, 10 and 30 degrees above the east southeastern horizon and will be glowing at magnitude +8.0, -2.0 and +5.9, respectively. Jupiter and Neptune will lie among the background stars of the constellation Capricornus, the Sea-Goat while Neptune will be found among the stars of the constellation Pisces, the Fish. A modest size telescope will be needed to observe Neptune, the Blue-Green planet while Uranus will be difficult to observe due to its proximity to the Sun. - KBK, GMANews.TV