Sirius Mysteries



No Dog Days Yet

Sirius the Dog Star is the brightest star in the nighttime sky. It has fascinated people around the globe and plays a prominent role in cultural myths. To the Egyptians it was worshipped as the "King of Suns," who based their calendars on its movements. The rising and setting of Sirius told the Egyptians when to plant, when to harvest, and when the Nile typically flooded. The phrase "Dog Days of Summer" originates in the ancient Egypt. During the hottest part of summer, the Sun stands high in the sky. And even though they could not see it, the Egyptians knew that Sirius was also nearby the Sun during the day. They claimed that the presence and brilliance of Sirius added to the intensity of the Sun's heat.

In Hindu mythology, Sirius was a hunter. This hunter was the father of 27 daughters represented in the 27 phases of the moon.

The Finnish poet Topelius wrote a poem hypothesizing that two stars fell in love and became one - he turned out to be correct Sirius has a small white dwarf companion circling it, Sirius B
which orbits Sirius every 50 years.

Two controversies surround Sirius. Ancient Greek texts claim that Sirius is a bright red star. In actuality Sirius is shimmering white. Did Sirius change colors over the years? Did the Greeks get this wrong? Was Sirius lower in the sky and therefore appear more red? We may never know.

The second controversy involves the mythology that the Dogon people of West Africa had about Sirius. According to French anthropologists who first met this tribe, the Dogon had a special reverence for Sirius and developed many unique rituals around this bright star. The Dogon legends say that aliens from Sirius visited their people 5,000 years ago. They perform a celebration every 50 years in honor of their alien visitors. Why every 50 years? The aliens told them that where they come from they have 2 suns, a smaller one that orbits the larger one every 50 years. It turns out that modern astronomy proved the existence of a smaller companion star (Sirius B) that orbits the main star (Sirius A) every... wait for it... 50 years! So the question still remains, were the Dogon really visited by aliens from Sirius or were they just given inside information from aliens from France?

Look for Sirius in the southwestern sky this March and April.

Sirius Aliens?

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Leo the Lion

Spring has sprung in Cincinnati and we can finally focus on the constellations of spring.

The first of the major spring constellations, Leo is recognizable by the six stars which form his head shaped like a backwards question mark - also called the sickle or fishhook. The bright star Regulus is the dot in the question mark and designates this King of the Beasts. The back end of Leo is marked by a triangle of stars - the farthest east being his tail, Denebola.

In Greek mythology, Leo may represent the Nemean Lion which ravaged the Mediterranean countryside long ago. The boldest, bravest hunters were sent out to kill Leo but faced a nearly immortal enemy. Leo had an impenetrable hide. When the hunters shot arrows at the lion, they just bounced off. When they tried stabbing him with the sharpest swords, no cuts could be made.

Hercules comes on the scene to kill the lion as the first of his twelve labors. This is where he shows that he has some brains (unlike the dimmer Orion). Hercules stalks after the killer beast and, at the most opportune moment, leaps onto Leo’s back wrestling him about the neck. Using his mighty muscles, Hercules squeezes and squeezes until Leo the Lion is strangled to death.

But Hercules isn’t all muscles. If you ever see pictures drawn of Hercules, you may notice his un-stylish clothing. After killing the lion, Hercules decided to keep Leo’s hide as a bullet proof jacket. Now he could walk down the street - and people would be shooting arrows at him or throwing knives - without fear. It was grrrrrr-reat.

Question from a smart second grader in the planetarium: “If Leo’s hide could not be cut, how did Hercules make it into a suit?”

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Canis Major, the Big Dog

Orion's hunting companion in the sky, Canis Major or the Big Dog, follows along to the left of the great hunter. Canis Major's brightest star, Sirius, is also the brightest star we can see from Earth. The constellation is extremely easy to find. If you connect the dots of the three stars in Orion's belt and continue that line to the left, you will run into Sirius, the Dog Star.

When Orion was placed up in the sky only to be trampled by the Bull each night (with Seven Sister's on its back), he asked the gods if he could bring his favorite hunting dogs with him to fend off the bull. Unfortunately for him, the dogs don't seem to be helping. The Little Dog (Canis Minor) is chasing after a Unicorn (the constellation Monoceros), while the Big Dog is barking after a little bunny rabbit (the constellation Lepus the Hare) at Orion's feet.

Canis Major's others stars include Mirzam, Wezen, Aludra, Adhara, and Furud - all Arabic names. Mirzam is "The Announcer" since it rises before Sirius crests the evening horizon. But I like Wezen which means "Weight". An old Arab legend says that this star seems heavy in that it rises from the horizon with great difficulty.

STAR GAZER Programs for March

I’m back from Miami Florida where I filmed another eight episodes for the iconic astronomy program – STAR GAZER. This is the show you see late at night on PBS where a guy stands on a light beam and tells you, “What’s Up,” in the sky. Well, for the third month, that guy has been me! I can hardly believe it - but now I’m able to share my passion for the night sky on 1-minute and 5-minute segments aired on over 90 TV stations around the globe. If you’d like to watch them, they’re on YouTube. I wrote Finding Direction in the Night Sky – where I get to tell my classic myth jokes. Check them out, “Like” them, and post comments please:

March 7-13 The Biggest Full Moon in 18 Years
5-minute: http://www.youtube.com/watch?v=eycsw-DZ9wg  
1-minute: http://www.youtube.com/watch?v=3Ng2wT3Azdw  

March 14-20 Finding Direction in the Night Sky
5-minute: http://www.youtube.com/watch?v=X7-bTOKeCUE  
1-minute: http://www.youtube.com/watch?v=A6AQAJ-pt9M  

March 21-27 Venus and the Moon at Dawn
5-minute: http://www.youtube.com/watch?v=WsZAg7VnPh4  
1-minute: http://www.youtube.com/watch?v=3n7lIM2ptro  

March 28-April 3 Arcturus and Saturn Join the Moon and Pleiades
5-minute: http://www.youtube.com/watch?v=mnqBioC7Fh4  
1-minute: http://www.youtube.com/watch?v=IgHwMujAY2Q  


You can download all of your favorite Star Gazer programs at: http://www.jackstargazer.com/JHSG_DNLD.html

If you don’t get Star Gazer on local your PBS station – let them know about it. The program is free for anyone to broadcast. Spread the word!

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Lepus the Hare and Columba the Dove

Below Orion's Feet

This week I'll focus on two fainter constellations that creep low across the southern sky in winter.  The easier one to see is Lepus the Hare who scampers from southeast to southwest below Orion's feet.  Although there is almost no mythology behind this constellation, it dates back to the original 48 star shapes documented by Ptolemy in 150A.D.  It's easy to make out the body of the rabbit - four fairly bright stars mark his body - and with a little imagination you might be able to visualize his front paws jutting out to the right with his ears streaming back to the left. 



The Bunny Rabbit

Lepus' position (below the much brighter Orion) led the Arabs to call this the "Throne of the Central One" (meaning Orion's platform.  Another legend calls the four brightest stars four camels drinking from the nearby river (the constellation Eridanus).  And to the Egyptians it was the boat of their main god/dude Osiris.


Moses' Dove

Below Lepus is a fainter constellation: Columba the Dove.  From Cincinnati, you really can only see Columba in the winter evenings since it barely clears the southern horizon.  If you live farther south (like in Florida), you'll have a better view.  Legend has it that Columba is the starry representation of the dove Moses sent out in search of land during the great flood.  It came back to the ark bearing an olive branch - a sure sign that dry land wasn't far.  Columba first appeared on star charts around 1600 to fill in the space below Orion and below the Hare.

Try to find these small constellations low in the southern sky before they move out for Spring.

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International Space Station Passes

Space Shuttle Discovery launched on its last mission on Thursday February 24 and rendezvoused with the International Space Station (ISS).  In Cincinnati we will have some great chances to see the ISS fly overhead.  Maybe we'll even be able to see Discovery detach from the ISS.  It'll look like a bright, unblinking star moving slowly across the sky.  Below are the dates, times and locations to look for the ISS above the Cincinnati area.  To find out when it passes over your town, please visit: http://www.heavens-above.com/

5 Mar    7:38pm-7:41pm moving NW to NE
6 Mar    8:03pm-8:06pm moving NW to NE
7 Mar    6:54pm-6:59pm moving NW to NE
7 Mar    8:29pm-8:32pm low in the NW
*8 Mar    7:20pm-7:26pm moving NW to E  **Brightest pass of the week**
*9 Mar    7:46pm-7:51pm from WNW to SSE *Another good one*  It will go right past the Moon!
10 Mar    8:15pm-8:18pm from W to S
11 Mar    7:05pm-7:10pm from WNW to SSE

*Check back later this week - times may change slightly due to the Space Shuttle docking and undocking
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Another Week, Another Crazy Astronomy Story

No, we're not going to have a Second Sun in 2012.



Sorry Luke...

 Last week it was the new zodiac, this week it's about Betelgeuse.  Have you heard about this?  A Senior Lecturer of Physics at the University of Southern Queensland, Dr. Brad Carter unleashed another media frenzy when he talked to a reporter about this star's impending destruction.  The article, picked up by everyone across the globe claims wrongly that the supernova of Betelgeuse (Orion's red-giant armpit star) will give us two Suns, a la the fictional planet from Star Wars, Tatooine.  My reaction, "Balderdash... pure balderdash".

What they got wrong:

1) Betelgeuse is the second largest known star in the universe.  Wrong -  it ranks around 10th in our galaxy.

2) It could go supernova as early as 2012.  Wrong - it go go any day, but there is no new evidence saying it will go by 2012.  This infamous date was added for effect (bravo reporter, sarcastic clap clap).  We will have no warning about it.  It could go today or 1,000 years from now.

3) When Betelgeuse explodes it will be as bright as the Sun and there will be no night for days.  Wrong - astronomers estimate that it will be no brighter than a full moon and won't appear that large.  From past accounts of supernovas, it should be bright enough to be visible in the day time - like a really, really bright star, and not bright enough to vanquish nighttime.

4) This will affect the Earth.  Wrong - Betelgeuse is so far away (over 600 light years) that the radiation, gamma rays, and other nasty stuff won't reach the Earth. 

Tycho's Supernova

The eventual exploding of Betelgeuse is not news.  I'm hopeful that it will explode in my lifetime, but I'm not holding my breath.  We're definitely due for a bright supernova.  The last two bright enough to be visible day and night were in 1572 and 1604.  (Those guys in the Renaissance had all the luck!).  The Supernova of 1572 was described in great detail by Tycho Brahe, Danish astronomer and loser of a nose in a mathematics-themed sword fight.  It shows up on old stars charts in the constellation Cassiopeia.  The Supernova of 1604 is often called Kepler's Supernova from the German astronomer Johannes Kepler, who came out of Brahe's shadow to become the leading astronomer of the 1600s.  Both of these supernovas blazed for weeks.  I can't wait to see one... any day now ;)

"Two Suns?" what poppycock!
Signed,
The Crabby Astronomer
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