Saturday, 29 January, 2022

Stars And Constellations Grace Clear Winter Sky


Dr. Rishi Shah

Spectacular sights of planets lining up in the western evening sky and eastern sky at dawn could be relished ravishingly this month. Other enthralling entities like stars and constellations that grace the clear winter night skies could be observed enthusiastically with fascination. The elusive fleet-footed planet Mercury would reach its greatest eastern elongation from the Sun on 07 January.
Mercury will be perceived briefly low above the south-western horizon after sundown until the middle of the month. It would be rushing through zodiacal constellations Capricornus (sea goat) and Sagittarius (archer). Planet Venus could be noticed tersely before sunup above the southeastern horizon from the middle of the month. Viewing it amidst the star-studded north-eastern sector of Sagittarius would not be so easy due to its proximity to the Sun.

The red planet Mars could be marvelled at a couple of hours before daybreak above the south-eastern horizon. It would be mingling merrily with shimmering stars belonging to the broad constellation Ophiuchus (the serpent bearer) and tea-pot resembling Sagittarius. The mighty planet Jupiter could be admired in the south-western sky for about two hours after sunset. It would be gleaming with the stars dwelling in the southern area of the constellation Aquarius (water bearer).

The ringed planet Saturn could be glimpsed for about an hour in the south-western sky after night-beginning during the first week of the month. It would glitter gorgeously on the northern side of the constellation Capricornus. It could be lost in solar glare later in the month. The greenish far-flung planet Uranus could be spotted as a glistening point of light in the south-eastern sky after sunset. It could be chased cheerily until midnight in the western sky in the somewhat barren southern region of compact constellation Aries (ram).

It can be discerned roughly below the giant star Hamal and above Mu Ceti, which are purely 65.8 and 84 light-years away respectively. They would inhabit constellations Aries and Cetus (whale) comfortably. The bluish distant planet Neptune could be applauded for a few hours in the south-western sky after dusk. It will be gliding across the north-eastern realm of the amazing Aquarius. The new moon would fall on 02 January, while the full moon (Swostani Purnima) dubbed popularly the wolf full moon could be manifested on 17 January 2022, because during this time of year hungry wolf packs would howl haplessly outside hunters’ camps.

Quadrantid meteor shower
The Quadrantid meteor shower would exhibit up to forty meteors per hour at its peak which would befall this year from the night of the 03 till the morning of 04 January 2022. Quadrantids would generally be active from 12 December to 12 January. A thin, crescent moon would set early in the evening, allowing dark skies for displaying an excellent show of scintillating shooting stars. The parent body putatively responsible for creating the Quadrantids has been identified as the arcane asteroid 2003 EH1, which could have been related to the mysterious comet C/1490 Y1, which Chinese, Japanese and Korean astronomers had accurately recorded five hundred years ago. 2003 EH1 had arrived at perihelion on 12 March 2014. Its orbital period has been calculated to be as sparse as 5.52 years. Asteroid 2003 EH1 has been classified as a near-Earth object.

It was recognised in March 2003 by astronomers of the LONEOS programme at Anderson Mesa Station in Flagstaff, Arizona, USA. Lowell Observatory Near-Earth-Object Search (LONEOS) is a NASA funded-project designed to discover asteroids and comets that orbit near Earth. The LONEOS venture began in 1993 and ran until the end of February 2008. Meteors would seemingly exude from the radiant, which would make an approximately right angle with the circumpolar constellation Ursa Major (great bear or big dipper) and the alluring red giant star Arcturus (Swati) that would be sparkling in the kite-shaped constellation Bootes (herdsman).
Awesome Arcturus would be barely 36.7 light-years away. The maximum meteors would streak luminously during the wee hours of the morning in the eastern sky in this part of our world. Meteor showers arise when the earth passes through streams of debris left behind by comets and asteroids.

The earth's yearly trail around the Solar System will carry it to its closest position since the Sun 0.98 AU. The average distance between Earth and the Sun has been accepted to be simply 150 million kilometres or one astronomical unit (AU). The earth's separation from the Sun would very exiguously by three per cent over the years because its path has been slightly oval-shaped and ellipse alike. In 2022, this day would occur on 04 January. Technically speaking, at perihelion the Sun would appear bigger in the sky than at any other time of year and when the earth would receive the most radiation from it. But in reality, the scant three per cent differences in earth's gap from the Sun would be hardly accountable for influencing any incidence.

James Webb Telescope
The world's most powerful NASA’s James Webb Space Telescope (JWST) lifted off last Christmas day from Kourou Space Centre in French Guiana on an exceptional journey to its outpost, lying utterly 1.5 million kilometres from earth. After some three decades of preparation and with an outlay of ten billion USD in the making, JWST left earth enclosed in Ariane-5 rocket.
Named befittingly after the former NASA director, JWST will follow in the footsteps of the legendary Hubble Space Telescope (HST). It will find out how the universe looked like after the hypothesised Bing Bang closer at its birth almost 13.7 billion years ago. JWST has been dispatched on a queer quest to peer deeper into the first-born stars and scouring galaxies for hints of life in its ultraviolet, visible and infrared vision.

The unprecedentedly large telescope had to be folded in origami style to fit into the rocket. Its mirror would measure 6.5 metres in diameter (three times the dimension of HST-mirror) that constitute eighteen hexagonal gold-plated beryllium sections. Protecting the observatory is a wispy, five-layered sunshield, vital for keeping the light-gathering mirror and heat-sensing infrared detectors at subzero temperatures. At twenty-one metres by fourteen metres, it would mimic a conventional tennis court. It would need a month to get there and another five months before its infrared eyes would be ready for scanning the cosmos.

It will be stationed much farther away than HST, which has been six hundred kilometres above earth since 1990. The JWST would be placed carefully at the stable Lagrange-2 location, where the earth, sun and moon would be on the same side of the sun-shield. JWST is expected to be fully functional and officially enter service probably in June 2022. NASA is envisaging its ten years of operational life. NASA has partnered with the European and Canadian space agencies to build robustly and launch perfectly this new exclusively seven-ton telescope with thousands of experts from twenty-nine countries working passionately on it since the 1990s.

(Dr. Shah is an academician at NAST and patron of Nepal Astronomical Society, NASO)