Sunday, November 22, 2009

Talk Programme on Astronomy and Meteor Science on Nov 22,2009

First row ( from left): Joe Malnar,USA;Jennifer Dudley Winter,Fred Bruenjes,Rishi Shah,Dr. Prakash Atreya and NASO Team.

Friday, November 13, 2009

Friday, November 6, 2009

November Sky:Meteor showers, mighty Jupiter and the Hunter's Moon

-By Kedar S Badu

This month, we have two meteor showers, the Hunter's Moon and Jupiter dominating the evening skies. But let's talk of the stars first.

Along the Zodiac, from east to west, you can now observe the constellations Taurus, Aries, Pisces, Capricornus and Sagittarius. Just below Aries the Ram, enjoy the brilliant constellation Cetus the Whale, with its reddish, super giant binary star Mira, which will vary in brightness over successive nights. Note that the tail of Pisces the Fish points directly to Mira. Though summer has already given way to autumn, the well-known asterism of the Great Summer Triangle is still visible in the western skies. The Great Square (Pegasus) is just overhead.



In the northern skies, you can easily identify the constellations Auriga the Charioteer, Perseus, Cassiopeia, Cepheus, Draco and Hercules from East to West. If you are away from dazzling city lights, enjoy the Milky Way, which stretches from the northeast to the southwest. Pre-dawn stargazers have the opportunity to enjoy the Big Dipper in the northeast and the Winter Hexagon (a group of bright stars around the constellation Orion) located just overhead. While watching the Big Dipper, don't miss the Great Galaxy (M81) that is located 15 degrees to the northwest from the star Dubhe. Note that the two stars of the Big Dipper, Merak and Dubhe, point straight to the Celestial North Pole (Polar Star).

Planet observing

Jupiter in Capricornus outshines everything else in the southern sky, save the moon. You can see its four largest moons and a couple of belts with a small telescope.

Saturn will rise in the east in the early hours of the morning, and is well up in the southeastern sky by dawn. It will move very slowly southeastwards towards Virgo.

Mars, getting brighter by the day, will rise in the northeast at around 11:30PM and will be high in the southern sky just before dawn. Catch it on the night of 2 November as it crosses the beehive cluster (M44).
Mercury will be invisible beginning 5 November as it passes behind the sun and Venus will rise before sunrise. Catch it low in the southeastern sky at dawn but be warned, it's getting gradually dimmer.

The Hunter's Moon - the particularly resplendent full moon that enables harvesting (not to mention hunting) past sunset - began on 3 September and will be 98 per cent full on 4 November. Catch it as it passes close to the Pleiades star cluster (M45).


Meteors


Two meteor showers occur about a week apart in November. The first is the Taurid shower, so called because meteors appear to shoot out of the constellation Taurus the Bull. This meteor shower begins around 4 November and peaks overnight on 11 November. Taurus will rise early in the evening so you won't have to stay up late. Don't expect too much since Taurid peaks at a mere eight meteors an hour.

The Leonids peak before dawn on 17-18 November and appear to come from the constellation Leo, which does not rise fully until after midnight. For early observers, note that Mars is leading Leo the Lion and Saturn is behind it. The radiant point is within the 'Sickle' of Leo, a hand's breadth to the left of Mars. There will be no interference from moonlight, giving you a good opportunity to enjoy the shooting stars. Meanwhile, sporadic (non-shower) meteors can be seen on any night, in any direction.

Source:Nepali Times,FROM ISSUE #474 (30 OCT 2009 - 05 NOV 2009)

Wednesday, November 4, 2009

Night Sky in November

-By Rishi Shah

The night skies of this month delightfully display many fascinating planets, alluring stars and other captivating marvels of the heavens. As darkness descends enchanting zodiacal constellations of Sagittarius (archer), Capricornus (sea goat), Aquarius (water bearer), Pisces (fishes), Aries (ram) and Taurus (bull) are seen unfurling across the sky from western to eastern horizon.

The great Square of Pegasus (winged horse) dominates the evening overhead sky. Attractive constellation Andromeda (chained princess) extends towards northeast from Pegasus, where the beguiling Andromeda Galaxy that is circa 2.5 million light-years away could be thrillingly observed. Constellations Cygnus (swan), Lyra (harp) and Aquila (eagle) drifting towards western sky. Their lustrous stars Deneb, Vega (Avijit) and Altair (Sravana) sketch imaginary winter triangle in the sky. Lengthy constellations Eridanus (river) and Hydra (sea serpent) are meandering in southeastern sky. Cetus (whale) and Piscis Austrinus (southern fish) are spreading glamorously with their coruscating stars Mira the variable and Fomalhaut that are 420 and 25 light-years away. Constellation Auriga (charioteer) is floating in northeastern sky. Its star Capella sparkles like a beautiful gem in the sky.

The shimmering veil of our galaxy the Milky Way unrolls mainly through Auriga, Perseus (legendary hero), Cassiopeia, Cygnus and Aquila. Circumpolar constellations Draco (dragon), Cepheus (king), Cassiopeia (queen) and Ursa Major (great bear) encircles Polaris (Pole Star or Dhruba Tara) that sits comfortably in Ursa Minor (little bear).

Planet Venus is dazzling in eastern sky before sunup in star-field of Virgo (maiden). Star Spica (Chitra) glimmers gorgeously to its south. Planet Mars is wandering through Cancer towards Leo. It climbs high in sky shortly after midnight. Mighty planet Jupiter is scintillating enticingly in Capricornus right after sunset. Ringed planet Saturn is glistening in Leo. Distant planets Uranus and Neptune are gleaming between Pisces and Aquarius and in the eastern part of Capricornus. Planet Mercury is hurrying towards Libra and Scorpius. Discerning it in solar glare is relatively difficult. Far-flung diminutive dwarf planet Pluto creeps inconspicuously above Sagittarius. Asteroid Vesta-4 is dashing through Leo. Asteroid Melpomene-18 rushes across broad Cetus. It could be perceived in southern sky soon after sundown through telescopes.

Leonid meteor shower is expected to peak during wee hours after midnight on 17 November, when plentiful shooting stars could be gleefully followed as they emanate from Leo in eastern sky. Leoinids originate as earth ploughs through the prolific debris stream left behind by their parent comet 55P/Tempel-Tuttle with orbital period of 33.2 years. Its radiant-point lies in Leo’s sickle asterism. Ruddy Mars and Saturn glitter gloriously to its north and south. Comet C/2007Q3 (Sliding Spring) is tumbling through the expanse of several resplendent galaxies that belong to Virgo-Coma Cluster. Comet-hunters could relish its awesome presence through optical aid before daybreak in eastern sky.

Queerly dinky asteroid dubbed 2009TM8 measuring barely seven meters across flew past our planet from a distance of 348 thousand kilometers (closer than moon’s path that stretches to average 384 thousand kilometers) with frightening speed of utter 29 thousand kilometers per hour. Even though asteroid hunters watch continuously for rogue space rocks that could pose any impact risk to earth, peculiarly petite asteroids that could smack earth and could inflict serious localized damage to earth could often go unnoticed.

Famous as starburst galaxy the titillating irregular dwarf galaxy IC10 adorns Cassiopeia. As a distinguished member of Local Group of galaxies, it harbours numerous newly formed lurid colossal stars, including the luminous X-ray binary star system that perhaps houses puzzling black hole. As it hides behind celestial granules and stars near the plane of our galaxy, its light is dimmed by intervening dusty surroundings. Its vigorous star-concocting domains are illuminated with reddish hue. It is fairly 2.3 million light-years away.

Charming cosmic towering pillars created by cold molecular gas and inky gritty clouds reside within star nursery designated as Sharpless-171 that lies modestly three thousand light-years away in Cepheus.

The nebular glow is powered by the young massive hot stars. Their energetic light boils away the opaque substances that fragment the region. It also brightens the blanketing hydrogen gas and excites it to shine as red emission nebula that tucks snugly in the active central sector of Sharpless-171. Spanning moderately twenty light-years across, this star cradle was entered as number-171 in the exhaustive 1959 catalog of emission nebulae that was compiled by famed American astronomer Stewart Sharpless.

For accumulating wealth of data to guide scientists seeking water on the moon Centaur rocket stage-impactor (left over from its last June launch on Atlas-5 rocket) separated elegantly from its mother ship that belonged to NASA’s Lunar Crater Observation and Sensing Satellite (LCROSS) and slammed with vehemence into the lunar surface.

Hubble Space Telescope (HST) and Lunar Reconnaissance Orbiter (LRO) that is sailing around moon in fifty kilometers high orbit. Many missions, including India’s Chandrayaan lunar orbiter had indicated that probable signs of hydrogen compounds were present in areas extending towards moon’s South Pole. Scientists now require time to confirm their findings on presence (or absence) of water on moon.

The full moon (popularly known as beaver moon) falls on 02 November, while new moon occurs on 16 November. The accompanying star chart approximately portrays the night sky over Kathmandu at around twenty hours local time during mid-November 2009.

(Source: National,The Rising Nepal,National English Daily,Nov 2,2009)