PAGASA: Comet, meteor shower visible in October

A bright comet, a meteor shower, and various stars and planets will give stargazers a treat this October, state astronomers said. The Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) said Comet 103P/Hartley will be visible on October 20. "The comet will pass within 17.95 million kilometers from the Earth on October 20 ... and will be at perihelion (closest approach to the Sun) on October 28, 2010," PAGASA officer-in-charge Graciano Yumul Jr. said in PAGASA's astronomical diary for October. He said the comet has an apparent magnitude of +5 and will be trekking among the background stars of the constellations Cassiopeia, Perseus and Auriga from the first day of the month and onward. But he said an observer must be familiar with the stars and constellations to be able to locate easily the comets’ location. "The use of binoculars and a modest size telescope will make it an easy target," he said. On the other hand, he said the comet may still be visible with the naked eye under a normal dark sky condition. Comet 103P/Hartley is a small comet that appears regularly, with an orbital period of 6.46 years. It was discovered by Malcolm Hartley in 1986 at the Schmidt Telescope Unit in Siding Spring, Australia. Its diameter is estimated to be 1.2 to 1.6 km. The October Orionids meteor shower will be active from October 17 to 25. "However, the nearly bright Full Moon interferes with this shower display," Yumul said. At maximum rates, the shower may reach 15 meteors per hour that may be observed at favorable sky condition, but sometimes there are lulls even during the traditional maximum peak nights of October 21 to 22. "The Orionids are fast meteors and also have fireballs. The radiant of the shower will be observed north of Betelgeuse, the brightest star in the constellation Orion, the Mighty Hunter," Yumul said. Yumul said the Square of Pegasus will take center stage in the Philippine night sky after sunset, a sign of the arrival of the northern fall. Northeast of it lies the Andromeda Galaxy (M31), the closest large spiral galaxy to the Milky Way Galaxy. "Under clear skies and with the aid of a star map and familiarity with the surrounding background stars, it can be seen as an elongated misty patch with the naked eye and can be easily viewed through binoculars and telescopes. The splendid W formation of stars known as the constellation of Cassiopeia, the wife of King Cepheus and the mother of Andromeda in the Greek mythology, lies to the left, while the constellation of Pisces, the Fish will be found at the lower right of the square of Pegasus," he said. Also, the famous equilateral triangle in the sky, known as the Winter Triangle, rises before midnight. The Triangle formed by the stars is composed of Betelgeuse, the super giant red star and the prominent star of the famous constellation Orion, Sirius – the brightest star in the sky of the constellation Canis Major (the Big Dog)– and Procyon, the brightest star of the constellation Canis Minor (the Little Dog). On October 9, the thin Crescent Moon will join up Mars and Venus in the west southwestern sky 30 minutes after sunset. Venus will be shining brilliantly below in the west southwestern horizon at magnitude -4.4 and will reveal an 11 percent illumination through a telescope. It will then disappear from view in the sky within the next few days. Mars will glow at magnitude +1.5 and will be found almost three degrees to the right of the thin Crescent Moon. The three celestial bodies will be found among the background stars of the constellation Libra, the Scales. Jupiter will be shining at magnitude -2.9 together with Uranus, which will glow at magnitude +5.7 on the east southeastern horizon. They will be found close to each other and will lie among the background stars of the constellation Pisces, the Fish. Neptune will be found among the background stars of the constellation Capricornus, the Sea-Goat and will be located 44 degrees above the east southeastern horizon. A modest size telescope will be needed to observe the bluish planet. Saturn returns to view in the early morning sky on the third week of the month while Mercury will be difficult to observe due to its proximity to the Sun during the month. — LBG, GMANews.TV