Monday, June 1, 2009

NIGHT SKY IN JUNE,2009

-By Rishi Shah

The clear night skies of this month display the awesome gathering of the planets and present many mysterious marvels of the heavens to sky-gazers. After sunset numerous constellations of peculiar sizes and shapes that are sketched by twinkling stars cover the entire sky. If one would view them carefully, the puzzling patterns would seem to become alive and express the nature of those characters that they have been conventionally dubbed after. Zodiacal constellations of Leo (lion), Virgo (maiden), Libra (scales), Scorpius (scorpion), Sagittarius (archer), Capricornus (sea goat) and Aquarius (water bearer) are stretching gorgeously across the sky from western to eastern horizon.

Constellation Bootes (herdsman) and Hercules (legendary strong man) are dominating the central sky at dusk. Petit Corona Borealis (Northern Crown) is squeezed in between them. Beautiful Bootes-star Arcturus (Swati) is sparkling splendidly next to tiny constellation Coma Berenices (Bernice’s Hair). It is simply thirty seven light-years away. Cygnus (swan), Aquila (eagle) and Lyra (harp) are sprawling in the eastern sky. Their resplendent stars Deneb, Altair (Sravana) and Vega (Avijit) draw the imaginary summer triangle in the sky. Diminutive constellations Sagitta (arrow), Delphinus (dolphin) and Equuleus (colt) are climbing the eastern sky. Norma (carpenter’s square), Lupus (wolf) and Centaurus (mythological half man half horse) are unfurling across the southern sky. Red super giant star Antares (Jesta) in Scorpius is coruscating fascinatingly on their eastern side. It is roughly six hundred light-years away. Circumpolar constellations Cassiopeia (queen), Cepheus (king), Draco (dragon) and Ursa Major (great bear) are sailing around Polaris (Pole Star or Dhruba Tara) that resides in Ursa Minor (little bear) conspicuously in northern sky. Faint constellations Camelopardalis (giraffe) and Lynx (fox-alike animal) are ascending the northern sky. The shimmering veil of our galaxy the Milky Way is rolling through Cassiopeia, Cygnus, Aquila and Scorpius.

Elusive planet Mercury could be discerned with patience low in eastern sky before sunup along with planets Venus and Mars. These three planets are gliding around Pisces (fishes), Aries (ram) and Taurus (bull). Planet Jupiter glistens in eastern area of Capricornus after midnight. Bluish planet Neptune could be located slightly above it. Uranus rises late at night. It can be glimpsed below the Circlet asterism of Pisces. Ringed planet Saturn shines gloriously in Leo. Stars Regulus (Magha) in Leo and Spica (Chitra) in Virgo are exhibiting their enchanting presence in the close vicinity of the ringed planet. Dwarf planet Pluto is in opposition to Sun on 23 June. It is relaxing lazily in Sagittarius adjacent to broad Ophiuchus (serpent bearer). Consisting of both emission and reflection nebula component exquisitely colourful Trifid Nebula (M20) bejewels rich Sagittarius. It is sheer five thousand light-years away. Another dwarf planet Ceres-1 (previously designated asteroid) is dashing through Gemini. Sporadic meteor shower Bootids peaks at dawn of 27 June in the eastern sky. The lurid flashes of shooting stars are witnessed when the left-over debris of its parent Comet 7P/Pons-Winnecke disintegrate in our atmosphere. Comet 29P/Kopff could be also admired well in the eastern morning sky in Aquarius, as it rushes around our Sun every 6.4 years.

Recently Astronauts aboard Space Shuttle Atlantis of the fifth and last mission rejuvenated Hubble Space Telescope (HST). They repaired and refurbished various subsystems and replaced the old instruments with modern and capable versions enabling HST to be scientifically more functional till 2014, when its more sophisticated successor, James Webb Space Telescope (JWST) with a price tag of about 4.5 billion US Dollars would commence its operation. JWST would scrutinize celestial entities in infrared spectrum.

HST is one of NASA’s versatile iconic space telescopes, which has been designed for observing and probing enigmas of universe. It was put into near-circular low earth orbit by Space Shuttle Discovery in April 1990. It weighs fairly eleven thousand kilograms and revolves around the earth in merely ninety seven minutes from safe orbital height of modest six hundred kilometers. Its mirror spans barely 2.4 meters in diameter. HST is a collaborative project between NASA and European Space Agency (ESA). It is named after the famed American astronomer Edwin Hubble (1889-1953) who introduced the confounding concept of expanding universe. It is one of NASA’s series of four Great Observatories satellites that include Compton Gamma Ray and Chandra X-Ray Observatories and Spitzer Space Telescope that are responsible for examining cosmic objects in specific electromagnetic spectrum.

HST has assisted experts to make mind-boggling discoveries in astrophysics and resolve long-standing conundrums. It has measured distances to Cepheid variable stars in Virgo Cluster more accurately and attempted to ascertain enticing Hubble Constant that elucidates the expansion-rate of universe. Hubble’s commanding position outside earth’s atmosphere allows it to take extremely sharp images. Ultra Deep Field photos of high resolution are exceptionally detailed and phenomenal. They gave us opportunities to perceive our early universe and have suggested the prevalence of baffling black holes in nuclei of nearby galaxies. The rare collision of Comet Shoemaker-Levy-9 with Jupiter in 1994 was uniquely captured and shown worldwide by HST. It has revealed Proto-planetary disks (so-called proplyds) in the Orion Nebula with possible evidence of extra solar planets (exo-planets) around sun-like stars. It has also recorded many intriguing Gamma Ray Bursts (GRBs). HST has analyzed far-flung dwarf planets like Pluto and Eris that inhabit the outer realms of our Solar System and promoted the understanding of our cosmos and its expansion in accordance with Hubble’s Law that states that velocity of galaxies receding from the earth is proportional to their distance from us and supports the hypothetical Big Bang Model which describes the initial conditions and subsequent development of our universe that began arguably 13.7 billion years ago.

If not re-boosted properly HST would slowly re-enter earth’s atmosphere by 2032 and burn-up. Since some surviving remnants would still fall on earth’s surface, HST would probably be permitted to meet its fiery end in controlled manner over open sea or over unpopulated region to avoid any material damage and human fatalities. As Space Shuttles would be retired from service in 2010 and human space flight missions would be conducted with Orion Spacecraft which like the famous Apollo Capsule is considered as reliable taxi for space explorations. Aastronauts would perhaps visit HST for de-orbiting HST in future in this new craft. Although HST’s cumulative escalated financial cost could have reached questionably now up to circa ten billion US Dollars in addition to ESA’s contribution of exclusive six hundred million EURO, HST has furnished invaluable information to the quest for knowledge for comprehending the universe, our origin and our eventual fate on blue planet earth.

The full moon popularly known as full strawberry moon enthralls avid Luna-fans on 07 June. The new moon occurs on 22 June. Sun is comes to the highest point in northern sky, when it arrives at the Summer Solstice on 21 June. We experience the longest day and shortest night on this day in Northern Hemisphere. The accompanying star map approximately represents the night sky above Kathmandu at around twenty hours local time during mid-June 2009.

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