On the one hand, the entire humanity, since the outbreak of COVID-19, is bound to be socially distanced from each other. But on the other hand, far away in outer space, the two giant planets, showing no concern of social-distancing, are getting close to each other just for a quick “hi-five”!
This rare moment, widely known as the Great Conjunction, is an astronomical event where two bright gas giants of our solar system, the Saturn and the Jupiter, will come close to each other and can be viewed in the evening sky for over next two weeks. The conjunction will culminate on the night of December 21.
Let’s try visualizing this event in the form a race where the Saturn and Jupiter are running on their respective lanes, which are nothing but their orbits, around the sun.
Here the Jupiter when compared to Saturn, is closer to the sun and thus will be moving on the inner side of the plane whereas the Saturn is positioned on the outer side.
It’s obvious that the Jupiter being closer will race faster, completing one revolution around the sun in less time than Saturn.
Jupiter takes around 11.86 years to complete one revolution around the sun, whereas Saturn takes around 29 ½ years.
Now being an observer from the Earth we see Jupiter racing faster from behind, approaching the Saturn and finally overtaking it, which usually occurs once every 20 years. For this month, it is destined to be on Dec 21!
What so special about this year’s conjunction?
Although the conjunction of Jupiter and Saturn takes place every 20 years, this year makes this contact quite special in the sense that the two planets will be exceptionally close with separation of just 1 tenth or 0.1 degrees for its observers on Earth.
The last time Jupiter and Saturn were this near was on July 16, 1623. The next time they will come again this close will take place only in 2080.TV Venkateswaran on https://vigyanprasar.gov.in/
As per the records by NASA, the last time the two planets were so close to each other was nearly 400 years back, and it is close to 800 years back when the two made such a close alignment during the night sky as it’s going to be on Dec 21 2020, making this spectacular contact to be called as the “Great Conjunction”.
What if they bump into each other?
The next obvious event, as most of us will assume, that the two might just bump into each other. But, fortunately, they will not as though they will appear very close to each other, they will be actually be hundreds of millions of kilometres apart in space.
All eyes on the sky, please!
To watch the Great Conjunction you can start by climbing to the top of any high storey-building, or just choose any field or a park that offers an unobstructed view of the sky and begin gazing in the south-west direction towards the Western horizon soon after the sunset.
Jupiter being closer will appear brighter, whereas the Saturn will be slightly fainter, and positioned slightly above and to the left of Jupiter on 21st December.
The planets can be viewed with an unaided eye, but having binoculars, if not a small telescope, will give a spectacular view of the two shining like one single bright object in the sky. What’s more! You may even get lucky enough to see Jupiter’s four large moons revolving around the gas giant!
The Next Great Conjunctions to eye on!
Venus and Mars are confirmed taking the next slot of conjunction on July 13 2021. Then, on April 5 2022, the Mars and Saturn will appear making a close contact, followed by Jupiter and Venus on April 30 2022.