How to see the Christmas star, the conjunction between Jupiter and Saturn
Eyes, binoculars or telescope pointed south-west after sunset on December 21: here are the tips of the experts to be spectators of the conjunction between Jupiter and Saturn
(image: Juan Carlos Casado / Nasa) w Ancora a few days and, at the solstice of December 21, Jupiter and Saturn will be aligned. So close in the sky, at least from our point of view, that it can appear as a single bright star. And, voila, the 2020 poinsettia is served. Here's how not to miss the show.The great Great conjunction
As we told you in detail here, on December 21st there will be the next Great conjunction, the two gas giants of our System Solar will reach almost the same astronomical coordinates in the sky. An event that occurs approximately every 20 years, but which in 2020 will have the scent of the extraordinary: Jupiter and Saturn, in fact, have not been seen so close since the Middle Ages.The Christmas star
Their extraordinary apparent proximity, less than a tenth of a degree, could make them indistinguishable to the naked eye, giving the impression that there is a single large and bright star there, quite low on the horizon, towards the southwest. in the sky. That is why the media have already renamed the event as the arrival of the Christmas star.That graphic of the planetary conjunction going around is NOT representative of what it actually looks like 🙃 but this one is, exactly for NYC & close for similar latitudes!
Made by @jameshedberg of @CCNYPlanetarium using @OpenSpaceProj & @NASAJPL data https://t.co/5VFU2SW7mu pic.twitter.com/GJTaVisjv6
- Prof. Emily Rice, Ph.D. (@emilylurice) December 11, 2020
To this we can add a little more Christmas folklore. As Paul Fellows, president of the Cambridge Astronomical Association reports, some have speculated that one of the great conjunctions of the past may have been the comet that pointed to the place of Jesus' birth to the wise men. Not being an event in itself so rare, it is in fact possible that a Jupiter-Saturn alignment around the year zero inspired the biblical story. "The two planets converging on a point on the horizon would seem to indicate a place, which could have attracted the sages to travel east to that point," said Fellows.
Naked eye, binoculars, telescope
Weather permitting, we will be able to see the Great conjunction of 2020 even with the naked eye, turning our gaze to the sky towards the south-west shortly after sunset (which in Italy, to be precise in Rome, will be at 4:42 pm ): the Christmas star will appear low on the horizon (better therefore to have a free field). The most acute, however, may be able to distinguish the two very close planets.Those who have the instruments available for observation will certainly be more advantaged. With simple binoculars, Jupiter and Saturn can be easily distinguished in the same field of view: Jupiter will be the brightest celestial body. A small telescope, then, should even allow us to identify the four Galilean moons around Jupiter, Saturn's ring system and its moon Titan.
For space and photography enthusiasts who want to try their hand at task of immortalizing this great Great Conjunction, NASA has made available here a guide with practical advice and technical specifications.
Bad weather?
If the weather is not favorable, there will be little to do. But if direct observation is not possible, it will always be possible to connect to astronomical observatories in other parts of the world, for example at the Lowell Observatory (Arizona, USA).One last tip. Start observing the sky already in these days: you will learn to orient yourself so as not to lose the alignment of December 21st and you will be spectators of the approach of the two planets night after night.
