Become an Amateur Astronomer – this lockdown
By- Heigrujam Meen Bhushan
We see the Sun, the Moon, Planets and Stars rising and setting in the sky, we are in fact experiencing the effects of the rotation and revolution of the Earth around the Sun – a great cosmic clockwork in action. Since ages across time and civilisations, the night sky has been inducing awe and beauty – a question and an enigma. The night sky from our backyard still thrills us. This lockdown due to Covid 19 pandemic one can taste amateur Astronomy – the backyard astronomy and experience those thrills and the spirit of enquiry like those of ancient astronomers. With modern gadgets like camera, binoculars and internet we are better armed and the thrill and the child like delight remain the same as those experience by ancient astronomers. This Lockdown to relish these feelings just look up into the night sky and enjoy. But first about the comet Neowise which recently ignited the joy of sky gazing.
On 24th July 2020 at about 7:30 pm, Comet C/2002 F3 Neowise was photographed with Nikon D5300 18-140 mm lens (13secs, f 3.5, iso 1250, 56 mm) and the next day with 50 mm prime (10 secs, f 1.8, iso 200, 50mm) with much improved noise level. Rain and cloudy sky foiled attempt to photograph days before. The comet was found about left of Merak by extending from Dubhe of Big Dipper (Saptarishi). The comet was dim about 4 or 5 magnitude of apparent brightness with its little fuzzy tail (magnitude 6 is just visible to naked eye under very good sky condition and 0 assigned to brightest stars historically by ancient Greek Astronomer Hipparchus about 2000 years ago, it is still in used with modern modification and quantification, less number means more brighter, more than 6 means not visible to the unaided eye). Next day its position changed a little towards left side. The comet will not return for about 6700 years. As comet are mostly made of ice, dust and rocky material, as it passes and comes closer towards the Sun, its ice and other gasses components vaporizes, and blows off by the Solar wind emitted by the Sun forming a ion tail and a dust tail pointing away from the Sun. The comet’s core photographed was greenish blue in colour. Interestingly, comets were also recorded as ‘thawanmichak mamei panbi’(star with tail) in ancient Manipur as early as 1572 and on 2nd tithi ( nini panba) Saturday, wakching (Dec./ Jan.) 1705 in the western sky (pp57 vol 1and pp19 vol 2, Chaitharol Kumpaba translated by Saroj Nalini Arambam Parrat). By the mid-august, Neowise will be too dim to be seen even with a binocular or a small Telescope even though it is the sky. With its tails reducing as it goes further away from the Sun, it will be difficult to recognize.
Igniting amateur Astronomy: What can you do tonight if sky is clear?
Just look up and admire the sparkling stars, breath and feel the silence, the vastness limitless sparkling night sky.
First unaided eye observation (description valid approximately till end of August, 2020)
North West: After the sunset, in the north western sky, the Big Dipper (Saptrishi) can be easily seen, extend the first two lower star Merak (Pulaha) and Dubhe (Kratu) towards north, you will find Polaris, the current Pole star also known as North Star because it is very very close to north direction. This is because the Earth axis when extend in space passes very near the star Polaris. So as the Earth rotates, the position of Polaris does not change and all stars seems to rotates around the Pole Star, hence it is known as Pole star or North Star or Dhruv tara. In the north western sky the last three star of Big Dipper form an arc (part of a circle), extend the arc, you will find a redgaint star Arcturus(Swati), an aged star that has depleted its core hydrogen just 37 lightyears from us, extend further you will find Spica (Chitra) a variable bluegaint star 20,000 times brighter than the Sun, extend further you will find a group of 4 semi bright in quadrilateral pattern of stars forming Corvus Constellation low in south western sky. To ease remembering the name and location is the sky, we say ‘Follow the Arc to Arcturus (from the last three star of Big Dipper) and spin on to Spica’ extend further you find Corvus constellation.
South East: Planet Jupiter is seen as the brightest object and Saturn a yellowish starlike left of Jupiter. Right side of the Jupiter is the teapot of Sagittarius. A possible alien signal called the wao signal! was discovered by Big Ear Radio Telescope, Ohio State University on 15th Aug. 1977 was discovered coming from this direction. Further right you can see the beautiful Scorpius Constellation with its red supergiant star Antares (Jayestha) – a star which appears in the flag of Brazil.
North Eastern sky: Northern Cross with its bluewhite supergiant star Deneb is high in north eastern sky. Also a pattern of three bright star – the summer triangle consisting of Deneb of Cygnus, Vega of Lyra (northeastern direction) and Altair (high in east direction) of Aquila constellation can be seen. Near the region of Summer triangle near Altaire is a dim constellation Velpecula where the first pulsar PSR 1919 +21 was discovered by a doctoral student Joycelyn Bell Burnell on 28th Nov. 1967. She called it LGM-1 for Little Green Man thinking to be beacon from Aliens. W shape constellation Cassiopeia is rising little late in the sky. Planet Mars and Uranus will be rising late in the eastern sky.
Early morning night sky: Two hours before sunrise, Venus (brightest in eastern sky) is rising in eastern direction along with Taurus constellation with its bright redgaint star Aldebran(Rohini). Mars (dim reddish and star like) will be almost overhead. Also you can see Pleiades (Krittika/ khongjomnubi in Manipuri) high in the eastern sky. Planet Mercury is seen rising low in the eastern sky. Also you can see Orion constellation rising low in the eastern sky, its star Rigel will be bright in south eastern sky.
Moon: 3rd August is full Moon. Moon will be rising in the eastern sky just after sunset. Moon and Sun will be in opposite direction from the Earth. As days passes Moon will be rising late diminishing in phases. Moon will move 360 deg/27.3days = 13.2 deg/day from east to west ie. backwards in the background of zodiac constellation, 27.3 days being the sidereal month ie. time to return to same position in the background of stars. Interestingly, in vedic astrology the zodiac is divided into 27 nakshatra suppose to be the 27 wives of hindu Moon God Chandra. Hence, the moon stays in each nakshatra each day. Each lunar day is called ‘tithi’ or thaban like nini pannba humni pannba in Manipuri.
Stars: The sky looks like a big sphere rotating around the pole star called the celestial sphere. The sky rotates 360 deg in 24 hr (a day is defined as exactly 24 hr) or 15 deg every hr. The sky with all the stars and planets will seems to rotate around pole star 15 deg every hour or 1 deg every 4 minutes from east to west. Next day, the sky advances by 1 deg (Earth’s revolution 360 deg/ 365 days = 1 deg approx) or 4 mins every day. As the days passes, the celestial sky seems to advance from east to west by 1 deg or 4 mins every day. In other words, if you see a star, say at 9:00 pm, next day at 9:00 pm the star will seems to rotate by 1 deg. from east to west or, the star will be in same position 4 mins earlier ie. 9:00 minus 4 mins. This also means the sky rotates 30 deg every month (360 deg/ 12 months = 30 deg/month). All planets, comets, Moon seems to move in the background of stars very slowly.
Star gazing using Binoculars:
Binocular specifications are generally 7 x 50 mm which means, magnification is 7 times and 50 mm is the diameter of the objective lens which determines the light gathering power or how bright an object will be to the eye revealing fainter objects in the sky.
Moon appears much closer, best is during waxing crescent Moon just after sunset in the western sky when the contrasts between light and dark areas of the craters are maximum. If you are lucky, you can see occultation ie. Planets and some bright stars passing behind the Moon whose timing are important for astronomical calculation. For steady view, a tripod or a stand can be used. Crater Tycho named after astronomer Tycho Brahe can be easily seen.
Milky Way (Akash Ganga/ Nighthou turen) looks like a stream of heavenly gems of various colours. Colours of individual stars and gaseous clouds can be seen. The colours of the stars indicate its temperatures. Milky Way can be seen stretching through Cassiopeia, the Northern Cross then to Sagittarius constellation and tail of Scorpius constellation.
Pleiades (Krittika/ Khongjomnubi) is a beautiful open cluster (a group of gravitationally bound stars formed from the same giant molecular clouds, they are like brothers) in Taurus constellation rising from the east visible in early morning night sky.
Double Cluster in Perseus constellation near Cassiopeia, consisting of two star clusters is always visible from most part of Northern Hemisphere. You will see this beautiful cluster rising late in the north eastern sky. The double cluster is actually blue shifted meaning they are moving towards us. In Greek Mythology, the cluster is supposed to be the jeweled handle of Perseus’s sword. Perseus is the son of Greek God Zeus. He perform many heroic act such as beheading Medusa a monster with poisonous snakes as hairs, saving princess Andromeda chained to a rock to sacrifice to a Monster Cetus send Poisidion God of seas, storms and Earthquakes. Andromeda later married Perseus.
Double double (Epsilon Lyre) of Lyra is easy to locate as it is near Vega (Abhijit). It will be high in the eastern sky. Though visible to unaided eye as a single star, through a binocular two stars are seen separately. The two are in fact, another two star system visible through Telescope. In 1980’s a fifth very dim partner was discovered using very advance technique called Speckle imaging.
Perseid meteor shower is visible to naked eye but is more beautiful with a binocular. This shower is going on currently and will be peak by 9 August till 14 August 2020. At its peak upto 60 or more meteors can be seen per hour. It seems to come mainly from direction between Perseus and Cassiopeia although it covers all the sky. The Meteor showers are form when Earth enters the streams of debris left by comet Swift Tuttle.
Andromeda Galaxy is visible to the unaided eye with apparent brightness of about magnitude 3.4, it is dim, seen as fussy flatten cloud about 6 times the size of Moon. It can be located using Cassiopeia. It will rise late in north eastern sky and visible throughout the night. It is the only object which is located outside the Milky Way galaxy visible to naked eye. It is some 2.5 million light years away and belong to a small group of Galaxies which our Milky Way Galaxy is a part called the Local group which is a part of a larger group of Galaxies called Virgo Supercluster. Andromeda Galaxy is blue shifted meaning its moving towards us and will collide with Milky Way.
Star Gazing using Telescopes:
If you are luck even to have even a small Telescope, it is like having a divine eye. You can see so many wonderful objects in sky provided you know where and how to look.
Planets: The rings of Saturn and four big moons of Jupiter can be seen with a Telescope. They can be seen rising in south eastern sky. Right side of Jupiter is the Sagittarius Constellation along with band of Milky Way. Jupiter will be the brightest object in the sky. Phases of Venus (like our moon) can be seen two to three hrs before sun rise and will be the brightest, rightly called the morning star (though not a star). Reddish colour Mars can be seen almost overhead, In fact, Planet Uranus is also present close to Mars but will be difficult to recognize as it is featureless and appears like a star. Mercury will rise low in eastern sky and its phases can be observed like Venus but with little difficulty.
Moon: The craters of the moon can be seen more magnified and clearer, Crater Tycho, sea of tranquility the area where Apollo 11 landed can be seen. After full moon on 3rd August, Moon will rise 48 mins late per day and diminish in phase till new moon on 19th Aug. Then it will rises in the western sky after sunset as crescent moon increasing its phases as days passes.
Double star: Alberio is a double star system consisting of a contrasting brighter reddish orange (amber) star and a faint bluish star in Cygnus constellation. They can be easily track in Northern Cross. Find Deneb the brightest star in Northern Cross, Debeb forms the tail, the tip of the Cross is Alberio. The double star are not related and are optical binary ie. just happen to lie close to the line of sight from Earth. Alberio was photographed way back and published in 1923 in Henry Draper catalogue. Later in 1978, after much research the brighter reddish colour star has a very close binary – a partner revolving around each other. A US Navy cargo ship is named after this star.
Mizar(Vashistha): Mizar with its fainter partner Alcor(Arundhati) is a binary star visible to the unaided eye. It is located in the middle of the last three ie. handle of Big Dipper (Saptarishi). They can be seen better through a Telescope. Mizar is known as Vashistha, one of the Saptarishi, and Alcor as Arundhati, wife of Vashistha, in vedic astrology. The Arabs and the Persians use these stars for testing their eyesight in the ancient past.
AstroPhotography: Photography of the night sky can be done using mobile camera and much better with DSLR. Stars, Milky Way, Deep sky objects too dim to see with naked eye will be reveal in photos taken. Lens with low f no. such as 1.8 can gather more light, making the photo with less noise. Wide lens with low f no can capture landscape with Milky Way. Nowadays adapter to attach DSLR to Telescopes are available. With a DSLR fitted to a Telescope a much better, magnified photos of Planets and deep sky object can be photographed. I have clicked Orion nebula some 1300 light years away with Nikon D5300, It was impressive. Rule of 500 for a full frame camera says the shutter speed should not be more than 500/ focal length in mm of the lens used otherwise stars photographed will not be dots due to Earth’s rotation but shows trails. You can overcome this limitation by having a motorised tripod which compensates the effect the Earth’s rotation. Besides Amazon.in, simple or motorised Telescope made in India can be purchase online from tejraj.com or from space-india.org. GOTO Telescope can be track using Astronomy Softwares. The telescope will track automatically when you click a star or a planet.
Astronomy Softwares: Desktop version (windows/ Linux/ Mac) Stellarium is a good free Astronomy software where you can see simulation of position of stars, planets, eclipses, deep sky object at current time (like live), in the past say at the time ascending throne of Maharaj Chingthangkhomba (Bhaygachandra Maharaj) on Sajibu (March/April) 7 ni panba, 1759, star Pushya (a star in cancer constellation) rises in the east ie. ascending of throne timing made according to this star. This can be verified and understand better. Star configuration can also be study in future say ten years after. These are for any places on Earth. Stellarium, android version for mobile is available in playstore on payment.
Starry Night is a commercial desktop software f or macOS and Microsoft Windows. It display a photo realistic night sky, view the night sky from any location on Earth or any position in the solar system, the nearby Milky Way, or the Local Group of galaxies; display any date and time for thousands of years in the past and future; animate time forwards or backwards at any rate; display of current imagery from Solar and Earth-observing satellites; Control most popular GOTO telescopes through a serial interface cable; display the sky using an all-sky photographic mosaic created from CCD imagery and more. Google sky, Redshift, Celestia are other good Astronomy software.
Amateur Astronomy is fun, educative and thought provoking. It’s also humbling making us realize how vast, beautiful, complicated, enigmatic the universe is and we the human species the only living creature in the vast Universe trying to make sense of what we observe and know. It is also about God as creator – the Universe, the laws of matter, energies and their interactions at quantum and cosmological level faintly reveling His greatness, His Passtime and perharps His smile. Physicist Max Born, Nobel Laureate said ‘I saw in it (the atom) the key to the deepest secret of nature and it reveals to me the greatness of creation and creator.’ Bhaktisvarupa Damodara Swami a pioneer in Science and Spirituality said ‘… it is not that we give a human shape or characteristic to a god or anything whimsically. Rather it is the revelation of God Himself to self-realized transdentalist.’ Amatuer Astronomy not only induces a spirit of inquiry but a spirit of spirituality – divinity as well.
Wishing you clear sky
****The writer is a Former Planetarian, Leo Planetaria, New Delhi, Former Head of Resource, CMeLT Planetarium, Dehradun and Former Head of Resource, Equinox Planetarium, Chandigarh. Queries and feedback may be mail to hmbhushan@gmail.com