Grand conjunction of Jupiter and Saturn on December 21: Here’s how to watch it

Jupiter and Saturn will come such close to each other that the two will appear like a double planet.

jupiter saturn conjunction, december 21 celestial event

Jupiter will take over and apss Saturn on December 21, an event that happens once in 20 years. (Representational image: Pixabay/Sergeitokmakov)

On December 21, the night of winter solstice a rare celestial event will grace the horizon, the conjugation of two biggest planets in the solar system. Jupiter and Saturn will come such close to each other that the two will appear like a double planet. The planets will be so close to each other that it will be difficult to see them separately with the naked eye.

Dr Arvind Paranjpye, director of Nehru Planetarium called this rare celestial event as ‘great conjunction’ as it is taking place after 1623, reports IE. On December 21 the angle between Jupiter and Saturn will be 0.1 degrees. They will form six minutes and six seconds arc with each other. This angle is smaller than the two sides of the moon that is 0.5 degrees.

The event happens once every 20 years. This conjunction of two giant planets is also the second time since the telescope was invented in 1609, pegging the interest of the astronomers even more. Such conjunction will be next seen in March 2080. This phenomenon will not bring any harm to mankind said Dr Paranjpye and there’s no harm to watch it in the night sky with naked eyes.

The event is so legendary that some foreign astronomical organizations are associating it with the star of Bethlehem that guides the three wise men in the Bible. However, unlike some media reports, this isn’t an eclipse. Jupiter won’t pass directly in front of Saturn, completely cutting its view, but naked eye would presume so.

How to watch the grand celestial phenomenon

Human eyes without any aid can see objects as close as 0.025 degrees or just five per cent the size of the moon. So on December 15 about half an hour after sunset, While facing west, one will notice a thin lunar crescent above the horizon. Jupiter and Saturn will be seen above the horizon. On Dec 16, the lunar crescent will appear below the planets. One will be able to see the planets separately but very close to each other till December 19 as the crescent moves further up. But on days between December 20 and 23, they will look inseparable.

To watch the phenomenon more vividly use a pair of binoculars. A spotting telescope or a low power telescope will help you want Jupitar overtakes and passes by the Saturn on the conjunction night. Jupiter’s four moons and Saturn’s rings will be visible with the aid of telescope or binoculars, said Preston Dyches, a producer at Jet Propulsion Laboratory in a NASA video.