September Skies Illuminate Cosmic Wonders

The cool night skies of this month would display perplexing planets, stunning stars, confounding constellations, and enchanting entities that embellish the heavens. Planet Mercury could be marked in the eastern sky before sunrise for a few hours. It would then be lost in the solar glare. It would be ascending the eastern sky after midnight in the constellation Leo (lion).  Resplendent star Regulus (Magha) would be scintillating below Mercury. Mercury would reach the greatest western elongation from the Sun on September 5. It would provide the best time for monitoring Mercury meticulously since it would be well above the eastern horizon in the morning. Planet Venus could be visualised in the western sky after sundown. It could be venturing vividly through the curious constellation Virgo (maiden). 

The shimmering star Spica (Chitra) and Sombrero galaxy (M104) could be viewed below Venus. They are astonishingly 262 and whooping 30 million light-years away, respectively. The red planet Mars could be marvelled at in the eastern sky before sunup. It would be rising above the eastern horizon. The congenial Castor (Kasturi) and the pensive Pollux (Punerbasu) would be gleaming in the charming constellation Gemini (mythical twins) above Mars. Orange-hued giant star Pollux would be sheer 34 light-years away. It boasts of an eerie extra-solar planet revolving around it. Castor has been a unique sextuple star system at sparsely 52 light-years from us. The massive planet Jupiter could be applauded in the southeast sky. It would evanesce during dawn. It would be coruscating with the stars that sketch the conspicuous constellation Taurus (bull). Arcane alluring orange star Aldebaran (Rohini) allegedly accounted as a follower of Pleiades, alias Seven Sisters (M45) in Arabic would be fulgurating below Jupiter. It would be circa 65 light-years away. The ringed planet Saturn would be spotted in the eastern sky after sunset during evening twilight. Saturn would be in opposition on September 8. It would be creeping closest to Earth and be bedazzled by the sun. It will be more effulgent than any other time of the year and will be visible all night long. Through modern telescopes, planet hunters could savour the sights of Saturn's rings and its fulgent moons.

Planet Uranus could be glimpsed in the eastern sky late after sunset. It would be gliding upwards in the southern sky. It would be slipping low towards the western horizon by day-begin. To the east of Uranus, planets Jupiter and Mars could be perceived prominently. It could be ascertained in the western region of the constellation Taurus. The overwhelming open star cluster, the Pleiades, with hot bluish embedded stars, would glitter gloriously in the bewitching reflection nebula above Uranus. It would be glowing from a dramatic distance of fairly 444 light-years. Planet Neptune could be ferreted out in the eastern sky before midnight. It would drift high in the southern sky and slowly descend towards the western horizon as the sun would herald the day. It could be recognised below the famed circlet asterism of the constellation Pisces (fishes). Planet Saturn could be picked up pleasantly to the west on Neptune. This blue gaseous planet, Neptune, would be at odds and make its tightest tryst with Earth on September 20. It would be immensely illuminated by the sun and be looking arrantly lambent. It could be cherished all night long. Due to its extreme span from us, it would appear as a tiny blue orb in powerful telescopes.

The full moon would be on September 18. This full moon has been addressed popularly as the corn full moon because corn would be harvested during this time of year. Its other moniker would be the Harvest full moon, since it would be leaning towards the September equinox. It would be 357,486 kilometres away. The moon would represent one of the four supermoons for 2024. It would be nearest to Earth and could seem slightly larger and lustrous than usual, though the difference would be difficult to notice with naked eyes. 

The moon's orbit around earth is not a perfect circle. It has an average length of 382,900 kilometres from Earth, but its so-called apogee and perigee (the closest and farthest approaches from earth) alter every lunar month due to tidal and gravitational forces exerting on the moon. When the full moon or new moon is near earth, it would be eponymously entitled "super moon." 

A peculiar puny partial lunar eclipse would unfold on  September 18 when the moon would pass through the earth's partial shadow (penumbra), and only a small portion of it would slide through the most tenebrous shadow (umbra). The eclipse would be manifest in most of North America, Mexico, Central America, South America, the Atlantic Ocean, Europe, Africa, western Asia, and southwestern Russia. The moon would pass through the earth's shadow between 07:59 am and 09:01 am. The eclipse could be watched from any location where the moon would be above the horizon at that time. It would not be seen by us since the moon would stay beneath the horizon during the eclipse. The September equinox would occur on September 22. The sun would shine directly on the equator, and almost equal amounts of day and night throughout the world would be experienced. It would welcome the first day of fall (autumnal equinox) in the Northern Hemisphere and the first day of spring (vernal equinox) in the Southern Hemisphere.

The mysterious Mars with minute two moons Deimos and Phobos have always mystified mankind since time immemorial. According to a recent analysis of seismic data collected by NASA’s Mars Insight Lander during 1480 days, vast oceans of liquid water have been lurking on Mars. However, these reservoirs of liquid water are available too far below Mars’ topology for us to obtain deftly. It would shed light on an important piece of the strange puzzle of the aquatic history of our dry and desiccated, dusty neighbour. As rovers scurry on Mars, gathering data on its geology, it has become more evident that the red planet was once loaded with water. Minerals, terrain, and features like ancient sere lake beds and deltas suggest that Mars was once pretty soggy. Since the layer has been probably detected at depths between basically 11.5 and 20 kilometres, water may not be accessible easily to humans. But they would help us divulge the Martian water cycle that had retained abundant water utilising for Mars' inhabitability in the past or for the living environment at present or in the future. Water is indispensable for our life.  The quirky question of whether Mars had ever supported the existence of life has fabulously fascinated us all for decades. Was Mars warm and wet, akin to Earth's climate, or was it cold and icy, making it unfavourable to life-evolution could be deemed a Mars conundrum that could perhaps be solved soon.

Asteroid-lovers admired amazing asteroid 194 Prokne during its opposition to the Sun on September 3 in the comely constellation Aquarius. It was distinguishable from 20:05 pm above our eastern horizon and hover to its highest point in the sky at wee hours of night above the southern horizon. It was imperceptible in the morning at around 04 AM. It sank towards the south-western horizon. 

At the same time Prokne would prance into opposition; it would be hugging earth and mimicking the bizarrely brightest fleck of light in the night sky. Prokne would be orbiting between Mars and Jupiter in the main asteroid belt. It has been classified as potentially non-hazardous because its trajectory would not bring menacingly into earth’s proximity. Prokne would tumble around the sun every 4.24 years. It would be merely 161.7 kilometres in diameter. It would spin on its axis every 15.68 hours. It was identified by German-American astronomer CHF Peters in 1879.

(The author is an academician, Nepal Academy of Science and Technology and Patron at Nepal Astronomical Society (NASO.)