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Join us for our live online talk as we look to the Great Conjunction on 21 December 2020, the closest approach of Jupiter and Saturn in four centuries, and examine whether similar events can shed light on the story of the Star of Bethlehem.

Brother Guy Consolmagno hosts BBC Sky at Night Magazine's Christmas lecture, 17 December 2020, on the Great Conjunction and the Star of Bethlehem.

Thursday 17 December 2020, 7pm GMT. Tickets are on sale now at £10.

On Thursday 17 December at 7pm GMT, planetary scientist and Director of the Vatican Observatory Brother Guy Consolmagno SJ will be discussing the close approach of the Solar System’s two largest bodies, creating a marvellous spectacle in the night sky: a single bright ‘star’ marking the run-up to Christmas.

We’ll be hosting the event live online, giving you the chance to put questions to the astronomer and author of books such as Turn Left at Orion, who will be speaking live from Tucson, Arizona, USA.

Brother Guy will also be covering great conjunctions of the past and how some are greater than others, looking at why the 2020 close conjunction is a truly historic event: the closest approach of Jupiter and Saturn of the telescopic age.

The speaker will also examine the known natural effects that could be compatible with the account of the Star of Bethlehem as written in the Gospel of Matthew, and the likelihood that such a phenomenon actually took place.

He will also look at how, despite astronomy being able to provide an answer to what caused the Star of Bethlehem to come about, from other standpoints it remains a mystery, one to be pondered rather than solved.

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You’ll be able to submit questions throughout the talk, and they’ll be put to the speaker in the second part of the presentation to be answered live by him.

About the speaker

Guy Consolmagno colour

Brother Guy Consolmagno SJ entered the Jesuits in 1989 and was appointed Director of the Vatican Observatory and President of the Vatican Observatory Foundation by Pope Francis in 2015. With a PhD in Planetary Science from the University of Arizona, his research explores connections between meteorites, asteroids, and the evolution of small Solar System bodies, observing Kuiper Belt objects with the Vatican's 1.8m telescope in Arizona.


Along with more than 200 scientific publications, he is the author of half a dozen popular books including Turn Left at Orion (with Dan Davis), and Would You Baptize an Extraterrestial? (with Paul Mueller). He currently serves as chair of the Mars Task Group on the IAU’s Working Group on Planetary System Nomenclature, and asteroid 4597 Consolmagno is named in recognition of his work.