Blog Archives

New Scary Posts for Halloween!

Here are my best posts on Halloween:


  1. History of Halloween, NEW
  2. My exploration of the myths of Werewolves! 
  3. Harvest Moons: 

A Leap of… Imprecise Astronomical Calculations

Simulated image of the path of the Sun during the Winter Solstice created by

Simulated image of the path of the Sun during the Winter Solstice created by

February 28th is the last day of the month, which means that this is not a Leap Year. As you probably know, every four years we add an extra day onto February assuming that we didn’t do so in the last 300 years. Since this is a somewhat confusing and imprecise system, I thought I’d devote some time to explaining it here.

The reason we don’t have a precise calendar with a nice round 365 day year is because calendars are based around a rather imprecise clock- The Earth. Because of the Earth’s dizzying running pace of 19 miles per second around the Sun, it actually turns nearly four extra quarter turns on its axis, which adds up to one extra day, and that is why we add an extra day on February 29th. But here’s the catch- it’s not actually a complete day, which means that after a few centuries, the accumulated time we lose by adding a day means that we get off track with the Earth’s cycle around the Sun. This is why we skip a leap year every 400 years. The year 2000 was a leap year, but the year 2100 won’t be.

I found this nifty little algorithm to help you figure out whether or not the current year is a leap year:

Ithe year is divisible by 400 then
it  is a leap_year
If the year is divisible by 100 then
If the year is divisible by 4 then it is a leap year.

In this video, you can see a fun look about the science and history behind this phenomenon, and how it relates to, -gasp- MY FAVORITE STAR- SIRIUS:

As you can see from the video, the human race has evolved a great deal of calendars over the years to precisely track the motions of the planet around the Sun: the Egyptian, Mayan, the Julian, and Gregorian. Even today, with our cesium laser powered atomic clocks, we still use this system as the basis for how the world tells time; as mammals we still respond to the cycle of our planet, its Sun, and its moon, and we depend on that to keep our lives in sync with the rhythm of the cosmos. Imperfect though it may be, it is what links us with the rest of creation.

So enjoy this non-leap year, and while you do, take a little time to think about how you are part of this great cosmic dance, and how our planet knows the steps even after 4.6 billion years.

Happy Stargazing!


New Pages- Today In Space History and Astronomy Myths and Legends: The Seven Sisters

Orion Spacecraft (artist's rendering)

Orion Spacecraft (artist’s rendering)

Hello Loyal Readers and Subscribers!

Just wanted to let you know that I’ve added a new page devoted to Astronomy History as well as current developments in the Space Program called “Today in Space History” At least once a week, I’m going to comb the web and the history books and report on new developments in space exploration as they develop. When nothing’s new, I’ll give you some info on history- recalling what happened on this very day in history, with facts on everything from the first chimp in space, to the discovery of gravity by Isaac Newton. In short, This new page is about space exploration- not only what’s going on now, but also the many discoveries, experiments, successes, and failures that made it possible.

My first post is about how NASA is celebrating the inauguration of President Obama, with a week long program of open houses, free stargazing tours, and discussions about the future of NASA with astronomers and astronauts. Here’s a taste of what I found:

For more titillating posts, please visit “Today In Space History”

Also, sit tight, tonight I’ll be coming out with an all new “Astronomy Myths and Legends” post, about the Pleiades, (or the Seven Sisters as it’s also called), one of the most beautiful star clusters in the night sky.


Hope this piques your interest, and see you later!


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.

Happy New Year

Happy New Years Eve Everybody!

As with just about every holiday, today bears a special astronomical as well as temporal significance: Today is the day where our little planet makes a complete path around the Sun.


As you can see, even though January is a winter month, Earth is actually closer to the Sun around January, but since the Earth is tilted, its rays don’t hit us in the Northern hemisphere as well. This is also why we perceive the Sun as sitting lower in the sky during winter.

So here’s a question: Why do we celebrate the New Year on January 1st? Well, a lot of it has to do with the stars- for centuries, people have based the new year on the appearance of stars. In fact, in the Stuart period, England produced a new observatory that helped standardize time, as well as geography:

That new observatory King Charles built was the Royal Observatory in Greenwich, which is where we get Greenwich Mean Time (GMT), the standard time for the whole planet. In addition, Greenwich is the site of the Prime Meridian, the imaginary line that conveniently divides the world in half, so we can keep track of the Eastern and Western hemispheres. In the 19th century, the English decided that Greenwich would be the standard for time as well as the beginning of the Western Hemisphere, and that a new year started at midnight, when a group of stars pass over the Greenwich observatory. To learn more about the observatory, click here:

The star Sirus in the constellation Canis Major (the great dog)

The star Sirius in the constellation Canis Major (the Great Dog)

However, way way before that, human beings used the motions of the planets and the stars to determine the time of year. One such star is visible tonight; the single brightest star in the heavens, the Dog-star Sirius (Hope some Harry Potter Fans appreciate this).

Now, I’ll go into the mythological history of Sirius later this week in a new page devoted to astronomy myths and legends, but for right now you need to know that Sirius is always just below and to the left of Orion, which is why some call it “Orion’s Dog.” Some say that the Ancient Egyptians based their calendars on the time in which Sirus passed over the peaks of the Great Pyramid of Giza, and then the Romans co-opted their system when they began the Julian calendar.


The Egyptians had good reason to revere Sirius; the coming of Sirius marked the annual flooding of the Nile River, which allowed the Egyptians to survive in the harsh desert. No wonder they chose to make its appearance the start of their year; it brought them life itself.

In addition to being bright, Sirius is HUGE (twice the size of our Sun), close (only about 8 1/2 light years away), and moving nearer towards us, which means that it will be brighter tonight then ever before.  It should appear at its peak at midnight tonight, so if you join us at Primland, be sure to check it out after your New Years toast. If you book a Tour of the Universe, one of our Star Masters would be happy to point out Sirius to you, and go into even greater detail with the significance of this unusual star.

But in the meantime, I wish you all a very happy New Year. Please visit back often as this site is just going to continue growing! I hope you’ve enjoyed it so far, and if you like what you see, forward it to your friends and leave a comment below!

Happy Stargazing!