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Historic Comet Landing!

Hi Everyone!

As I’m sure you probably know, this is the very day that NASA’s Rosetta spacecraft has landed on a comet to peer into an object that has fascinated and terrified humanity for thousands of years! If you click on the link below, you can see the official NASA page of the mission, with pictures, a timeline, and video coverage of the mission. 

In honor of this momentous occasion, I’ve created a short presentation for you about comets. Feel free to use it in class, but please give me credit!

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I’ll be writing more later in the week about the significance of this mission, but for now, enjoy this presentation, and enjoy watching this incredible mission online!

Happy Comet-Gazing!

New Page uploaded!

Hi Everyone,

I’ve added a new page called “Astronomy Myths and Legends,” where I give you some research on the myths and stories associated with a particular planet, star, or constellation. Today I’ve posted a few myths and legends on Sirius, in the constellation Canis Major, the brightest star in the sky! Hope you enjoy it:

On the Twelfth Day of Christmas…

Hello Everybody!

January Sixth is the date where Christians traditionally celebrate the Three Wise Men or Magi finally reaching the Christ child in Bethlehem after following a new star in the east. Since this date is so closely associated with astronomy, I thought I’d examine some of the theories surrounding this story. A few weeks ago, Primland Astronomy hosted Father Chris Corbally from the Vatican Observatory, who came and gave his theories as to whether the Star of Bethlehem could have been a scientific phenomenon. The three prevailing theories are that the star was either a comet, a supernova, or a planetary conjunction which would have given the appearance of a new star, since it gave off the combined light of several planets.

Giotto Scrovegni- "The Adoration of the Magi", painted 1306. Notice the comet-like Star of Bethlehem, which might have been inspired by Halley's Comet, which appeared in 1301.

Giotto Scrovegni- “The Adoration of the Magi”, painted 1306. Notice the comet-like Star of Bethlehem, which might have been inspired by Halley’s Comet, which appeared in 1301.

The Comet Theory

Comets have long since been portents in the lives of kings. For example Julius Caesar was killed the same year as comet, and William the Conquerer assumed the throne on Christmas Day in 1066, the same year that Halley’s comet appeared over England. Furthermore the description of the star of Bethlehem moving across the sky and hanging over the manger sounds the most plausible with a comet, as opposed to a fixed star. Thus, there is a lot of symbolic evidence to support the claim that the star was really a comet, which is one reason why it was immortalized in this painting by the early renaissance artist Giotto (right). However, the problem with this theory is that comets are equally associated with ill omens, and that the closest comet visible in Bethlehem appeared sometime in the period 9 March to 6 April 5 BC and lasted over 70 days (Source: Colin Humphreys, “The Star Of Bethlehem” From Science and Christian Belief , Vol 5, (October 1995): 83-101. Accessed January 5th from

). If you take this date as the literal truth, this would mean revising the date and year of Christmas.

The Supernova Theory

Type 1A Supernova around an eliptical galaxy (Hubble)

Type 1A Supernova around an eliptical galaxy (Hubble)

A supernova is an exploding star, that becomes millions of times more bright than its entire life cycle, and then burns away into space. The advantage of going with supernovas instead of comets as a candidate for the Star of Bethlehem, is that they are so bright that they are visible in broad daylight, which would explain why the shepherds and King Herod saw the star too (Humphreys). As you can see in the photo on your left, the In addition, since comets generally follow a pretty predictable path, astronomers like the Magi might be less impressed with a comet than with a supernova, which only occurs once every 500 years, and was not well-known to ancient astronomy. Chinese astronomers record a supernova that happened around 5BC, but unfortunately, western records to not confirm it (Corbally). This could just mean that the supernova occurred too fast for most astronomers to observe it, except for the Magi, who were part of a religious sect that specifically went after heavenly signs. If you watch the documentary above, it mentions that there really were a small group of astronomers who called themselves the Magi out of Persia, and they followed astronomy closely as portents of the future.

Planetary Conjunction

One of the big hoaxes of 2012 was the theory that the planets were all going to align and throw the gravitational constant of the universe out of balance and destroy the Earth. Real planetary alignments or conjunctions can lend unusual light to the planets as they share the same space in the night sky. In fact, if you peruse Dr. Corbally’s website, he suggests that the triple conjuction of Jupiter and Saturn in 7BC that made a beam of light appear to fall from the two planets down onto Bethlehem, just like some Christmas cards depict.

Ultimately, this is an article of faith. Dr. Corbally also suggests that the Star could have been a divine intervention, which is neither provable or disprovable to science. However, it has captured the imagination of a great deal of artists, philosophers, theology scholars, and of course, astronomers. As I said before, the stars are a rich territory for myth and legend and when we look at questions like this we re-connect with what makes us human.

Happy Twelfth Night everybody! I hope this post gave you some epithany’s of your own.