STAR GAZER
THE INTERNATIONAL EDITION
Lorain County JVS NASA CORE / 15181 Route 58 South / 440/775-1400
/ FAX 440/775-1460 / nasaco@leeca.org / http://core.nasa.gov
 Click Here |
 Click
Here |
Horkheimer: Greetings, greetings fellow star gazers. You know it seems that almost everyone's favorite winter constellation is Orion the hunter. But his two faithful hunting companions, Canis Major and Canis Minor, should not be overlooked because their brightest stars are quite wonderful. Canis Major is Latin for the bigger dog and Canis Minor is Latin for the smaller dog. So go outside this month and observe this cosmic dog show.
O.K., we've got our skies set up for any night the next couple of weeks between 7 and 9 p.m. your local time facing due south where the most obvious constellation will be Orion the Hunter. Three bright stars in a row mark his belt, two bright stars mark his shoulders and two bright stars mark his knees. And to find his two faithful hunting dogs all you have to remember is that they always follow him across the sky. To find his first dog use the belt trick. Simply shoot an imaginary arrow down through Orion's belt and that arrow will land smack dab on Sirius which marks the eye of Orion's bigger dog and which is also the brightest star we can see with the naked eye.
Now many people draw a stick figure of a dog here in different ways but the one we're showing is my personal favorite. Sirius is mentioned in practically every culture that ever kept records. Even in ancient Egypt it was called the Dog Star and whenever it was first visible rising before the Sun in early morning it was used as a predictor that the Nile River would soon flood and make the land of Egypt fertile for planting. And if you've ever heard of the hot dog days of summer well this Dog Star was incorrectly blamed for it.
Today we know that Sirius is among the very closest of all the stars, only 8.6 light years away which means that the light we see actually left Sirius 8.6 years ago which is really close. So its closeness has something to do with why it appears so bright although we have to add the facts that it is almost twice as wide as our Sun and because it is so much hotter is 23 times brighter! Additionally it has a special companion star called a white dwarf. Special because even though it has the same mass as our Sun it is only two Earths wide, which makes its material so dense that a teaspoon of it would weigh several tons on Earth. Wow!
Not to be out done, the brightest star of Orion's other dog Procyon, although not quite as bright to the naked eye as Sirius, is even bigger, 2.3 times our Sun's diameter. But because it is not as hot a star as Sirius it shines only 6 times brighter than our Sun. It too, like Sirius, is close, only 11.3 light years away, 2 and a half light years farther than Sirius. And strangely, like Sirius it too has a white dwarf companion star almost identical to Sirius' white dwarf. So there you have it, the two brightest stars of Orion's faithful companions, each with their own special companion, which to my way of thinking is really something to howl about. Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
| Click Here |
Click
Here |
Horkheimer: Everyone loves Orion the Hunter but his two dogs hide hidden wonders. Early evening face south shoot an arrow through Orion's belt and you'll land on Sirius the eye of Orion's bigger dog, the brightest star we can see with the naked eye. It's almost twice as wide as our Sun but 23 times brighter and has a hidden companion called a white dwarf star whose material is so dense a teaspoon of it would weigh several tons on Earth. Procyon the eye of Orion's other dog is 2 1/3 times our Sun's size and 6 times brighter. And strangely it too has a white dwarf companion star almost identical to Sirius' white dwarf. Who says it's not a dog's world! Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
* This week's Sky At A Glance and
Planet Roundup from Sky & Telescope.
This week's Sky At A Glance displays current week only.
Starry Night Deluxe was used to produce this episode
of Star Gazer
Lorain County JVS NASA CORE / 15181 Route 58 South / 440/775-1400 / FAX 440/775-1460 / nasaco@leeca.org / http://core.nasa.gov
| Click Here |
Click
Here |
Horkheimer: Greetings, greetings fellow star gazers. Spring officially
begins next Monday March 20th. And as most of you regular star
gazer viewers know every year on the first day of spring the Sun
rises and sets exactly over the yellow line in the middle of all
roads running due east and due west. But in case you're one of
those who doesn't know why, let me elucidate.
The first moment of spring is really an astronomical moment in time, the precise moment our Sun lies smack dab on the celestial equator. That moment this year is 1:26 p.m. Eastern Standard Time, or your local equivalent, Monday March 20th. But what you may ask is the celestial equator? And what does it have to do with the yellow line in the middle of the road? Well for simplicity's sake let's simply imagine that we can take our Earth's equator and extend it way out into space so that it draws an imaginary line completely around the night sky thus dividing the heavens into two halves, which we call the northern celestial hemisphere and the southern celestial hemisphere.
Now if we could dim our Sun way down like a light bulb on a dimmer and keep track of its position against the background of stars day after day all year long we would notice that on the first day of spring the Sun is smack dab on the celestial equator. Then if we kept track of it day after day we would notice that it would move a little bit farther north of the equator each day until on the first day of summer it would reach its highest point north of or above the celestial equator. Then it would slowly move a little bit farther south each day until on the first day of autumn it would once again be smack dab on the celestial equator. Thereafter it would continue to travel south of the equator until it would reach its southernmost point on the first day of winter. And then it would seemingly reverse and start to travel north again until once again on the first day of spring it would be smack dab on the celestial equator. Simply try to remember that each year the Sun is at its northernmost point on the first day of summer and at its southernmost point on the first day of winter. And that on the first day of spring and fall it is always smack dab on the celestial equator. But how does all of this look from Earth?
Well the Sun, as seen from Earth on the first
day of summer, rises and sets at its most northern points on the
horizon and on the first day of winter it rises and sets at its
most southern points on the horizon. But on the first day of spring
and fall when the Sun is on the celestial equator it always appears
to rise exactly due east and set due west. So if you're driving
to and from work at Sunrise and Sunset on a due east/west highway
the Sun will rise exactly due east over the yellow line in the
middle of the road and set exactly due west over the yellow line.
And if it doesn't then your due east /west highway is not running
true east and west. It's that simple. So put your sun visors down
next Monday and keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
| Click Here |
Click
Here |
Horkheimer: Spring officially begins next Monday March 20th. The first moment of spring is the precise moment our Sun lies on the celestial equator which this year is 1:26 p.m. Eastern time Monday the 20th. Now the Sun lies on the celestial equator only two days each year, the first day of spring and the first day of autumn which makes for a strange phenomenon, because on these two days the sun will rise exactly due east and set due west which means that if you're driving to work at sunrise on a due east highway the sun will rise directly over the yellow line in the middle of the road and at sunset will set directly over the yellow line. And if it doesn't your highway is not true east and west. So put those sun visors down next Monday and keep looking up!
Please give us your comments. (Click
Here)
* This week's Sky At A Glance and
Planet Roundup from Sky & Telescope.Starry Night Deluxe was used to produce this episode
of Star Gazer
Lorain County JVS NASA CORE / 15181 Route 58 South / 440/775-1400 / FAX 440/775-1460 / nasaco@leeca.org / http://core.nasa.gov
| Click Here |
Click
Here |
Horkheimer: Greetings, greetings fellow star gazers. It's that time of year again when the night skies almost shout, "Spring is here" because Leo the Lion is chasing Orion and replacing him as the major constellation of the new season. Let me show you.
Now most of you know that Orion the Hunter is winter's most famous star pattern. Indeed if you go outside in early evening in December Orion is climbing up the southeastern skies as a celestial announcement of the imminent arrival of winter. And in January and February when winter is coldest Orion reaches his highest point in the heavens in early evening almost bragging that he is master of the season. But then things begin to change because all through March Orion slowly relinquishes his high flying position in early evening and by the beginning of April is tipped over on his side in the southwest, almost hanging on to the sky for dear life. And it is this position of Orion in the southwest heavens in early evening that always tells us that winter is soon coming to an end.
And although I am always sad to see Orion's bright stars go, nevertheless a much bigger although less bright constellation takes his place almost overhead in early evening, Leo the Lion, roaring that he is master now and that he and he alone dominates spring's skies. In fact if you go out any night in late March or April in early evening you will see Leo casually reclining almost overhead very self assured that winter and Orion will soon be completely gone. Now Leo is usually depicted reclining in a kind of sphinx position like the ancient Egyptians depicted him. His head and forequarters are indicated by a backward question mark with the bright blue-white star Regulus marking his heart. His rear is marked by a triangle of stars with Leo's second brightest star Denebola. In ancient times lions were often associated with royalty, in fact Leo's brightest star Regulus means "The Little King".
But little it is not. Some latest measurements indicate that it is more than one and a half times the diameter of our almost one million mile wide Sun. But because it is a much hotter star it is 140 times brighter. And because it is a whopping 80 light years away, when we look up at Regulus this spring we see the light that left it 80 years ago. But Regulus' second brightest star also outdoes our Sun. Even though it is closer, 40 light years away, it is almost twice as wide as our Sun, and also being hotter makes it 20 times brighter! Which means that if we moved either Denebola or Regulus as close to Earth as our Sun is we'd all be crispy critters. So, welcome in springtime the cosmic way. Simply go outside any night in late March and April, look toward the southwest where you'll see Orion on his way out and then look almost overhead where you'll see Leo the Lion king of springtime skies. Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
| Click Here |
Click
Here |
Horkheimer: Spring is here because Leo the Lion is replacing Orion. Look southwest and you'll see Orion's bright winter stars getting ready to exit making way for the much bigger constellation Leo, king of springtime skies. Leo's two brightest stars put our Sun to shame. Regulus is one and one half times bigger and because it is much hotter, it is 140 times brighter. Leo's tail star Denebola is twice as wide as our Sun and even though it's not as hot as Regulus it is 20 times brighter. So if we moved Denebola and Regulus to where our Sun is we'd all be crispy critters. Say good bye to winter's Orion and hello to springtime's Leo the lion. Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
* This week's Sky At A Glance and
Planet Roundup from Sky & Telescope.Starry Night Deluxe was used to produce this episode
of Star GazerLorain County JVS NASA CORE / 15181 Route 58 South / 440/775-1400 / FAX 440/775-1460 / nasaco@leeca.org / http://core.nasa.gov
| Click Here |
Click
Here |
Horkheimer: Greetings, greetings fellow star gazers.
Starting this weekend the Moon pays three wonderful visits to
three sky objects. First the Moon not only visits but actually
passes in front of the Seven Sisters. Second it has a lovely meeting
with Mars and then drops in to see ringed Saturn. Let me show
you.
O.K., we've got our skies set up for just after sunset just before it gets completely dark out this Saturday, April Fool's Day night, facing west where you'll see an exquisite three day old crescent Moon complete with earthshine which will look like a black full Moon nestled within the crescent parked right in front of the Seven Sisters. Of course you won't be able to see them until a little while later which means you should take a lawn chair out and spend some time outside because as it slowly gets darker this beautiful Moon will slowly reveal the wonderful star cluster we call the Seven Sisters or the Pleiades, which look like a tiny little dipper of stars.
Now the Moon doesn't get this close to the Sisters that often, only when the Moon is experiencing a major lunar standstill, which results in the Moon rising and setting much farther north and south than our Sun ever can. We are in a major standstill right now so the Moon and the Pleiades will come this close a few times over the next few months but because the Moon will often be much brighter the Sisters won't always look as bright as they will this weekend because this weekend there will be very little Moon light to overpower the faint light of the Pleiades. Don't miss this please. And if you've got a pair of binoculars, by all means use them because the sight will be absolutely spectacular, guaranteed.
And while you're out there keep in mind that this weekend our Moon will be only 231,000 miles away while the Pleiades will be a whopping 410 light years away which means that when you look at the Moon this weekend you will see the light that left it only a second ago while the light you see from the Pleiades this weekend is the light that left them 410 years ago. On the next night Sunday April 2nd the Moon will have passed beyond the Pleiades and will be headed for tiny 4,000 mile wide, Mars. And the next night Monday April 3rd it will be only 5 degrees away from Mars so you can use the Moon as a Mars finder. On Tuesday the 4th and Wednesday the 5th. It will be on its way to 75,000 mile wide Saturn. Then ta da! On Thursday April 6th the Moon will be only 8 full Moon widths away from Saturn so you can use the Moon that night to find it.
So there you have it, in early evening this
Saturday, April Fool's Day night the Moon mysteriously reveals
the beautiful Seven Sisters, on Monday you can use the Moon to
find Mars and on Thursday you can use it to find Saturn. And please
I beg you to use a pair of binoculars this Saturday to watch the
slow peekaboo uncovering of the Seven Sisters. It will take your
breath away. Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
| Click Here |
Click
Here |
Horkheimer: This weekend the Moon plays peekaboo with the star cluster called the Seven Sisters. Just after sunset, before it gets completely dark, Saturday April Fool's Day night face west and you'll see an exquisite three day old crescent Moon right in front of you. Then if you wait until it gets completely dark out you can watch this lovely crescent slowly uncover the tiny dipper shaped cluster of stars, the Seven Sisters. Use a pair of binoculars please because this slow uncovering will knock your socks off. The Moon will be only 231,000 miles away Saturday. But the Pleiades will be 410 light years away, which means that the light you see from the Sisters left them 410 years ago. Wow! Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
* This week's Sky At A Glance and
Planet Roundup from Sky & Telescope.Starry Night Deluxe was used to produce this episode
of Star Gazer
![[SmilinJack]](jack1sm.jpg)
Return to the [STAR
GAZER Main Page]