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
Horkheimer: Greetings, greetings fellow star gazers and in case you think the full moon this Wednesday and Thursday night looks bigger than usual, you're absolutely right because this week's full moon is the closest of the entire year at a scant distance of only 222 thousand miles away which is 30 thousand miles closer than the farthest full moon of 2001 on September 2nd when it will be 252 thousand miles away, which means that Wednesday and Thursday nights' full moon will look 14% larger and 30% brighter. Don't miss it!
And now, if you go out Wednesday, February 14th, Valentine's Day night between the hours of 8 and 9 p.m and look due south you'll see what I like to call the Valentine's Day star because every Valentine's Day night between 8 and 9 p.m. you'll see a very bright red star shining at its highest above the horizon. In fact it is the brightest red star we can see with the naked eye. And just coincidentally it reaches its highest point above the horizon every Valentine's Day between the hours of 8 and 9 p.m. It marks the shoulder star of the great sky giant Orion the Hunter and its name is Betelgeuse which in arabic means 'the armpit', which isn't very romantic for Valentines Day. But if you want to give your beloved a really big Valentine, well this is about as big a one as you'll ever find.
You see, if we compare Betelgeuse, our Valentine star with our own star, the sun, and our own planet earth, you will understand just how big. Now we all know that our 8,000 mile wide earth is pretty dinky compared to our 865 thousand mile wide sun. In fact we could fit over 1 million earths inside our sun. Betelgeuse, however, is so humongous we could fit over 160 million of our suns in side it! And that's when it's at its smallest size. You see, Betelgeuse is one of those stars which changes its size regularly like a slowly beating heart. It beats about once every 6 years and when it is fully contracted and at its minimum size it is about 500 times the diameter of our sun but when it expands to its maximum size it is almost 900 times as wide. Or if you care to think of it this way, if we could place Betelgeuse where our sun is, even when it is at its minimum size, it would stretch out past the orbits of Mercury, Venus, Earth, all the way to Mars. But when it's at its maximum it would reach all the way to Jupiter. Wow!
So there you have it, a humongous cosmic Valentine.
A giant red star slowly beating like a heavenly heart for your
sweetheart, courtesy of our local galaxy, and you can see it any
and every clear Valentine's night, between 8 and 9 p.m., at its
highest above the horizon, just look due south. Plus this week
you can also give your loved one the biggest full moon of the
year! Is this a romantic cosmos or what? I'm Jack Horkheimer,
Keep Looking Up!
Horkheimer: Want to give your
sweetheart the biggest, reddest Valentine ever? Then go outside
with your honey Valentine's Day night between 8 and 9 P.M., Face
due south and you'll see the brightest red star visible to the
naked eye from planet earth at its highest point above the horizon.
It is the shoulder star of Orion the Hunter and is named Betelgeuse.
It slowly pulsates like a giant heart and is so huge that if we
could place it where our sun is it would reach out past Mercury,
Venus, Earth, Mars and when fully expanded, all the way out to
Jupiter. So this Valentine's Day give the biggest valentine of
all, a giant red star, pulsing like a heart full of cosmic love.
I'm Jack Horkheimer, Keep Looking Up!
* 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
Horkheimer: Greetings, greetings fellow star gazers and have you ever wondered why the stars of winter are always the brightest of any season of the year? Well, I used to jokingly tell people that winter stars are brighter than any other season so you don't have to spend so much time outside in the cold trying to find them. And while that's not true, nevertheless it is comforting to know that to see winter's finest stars all you have to do is pop your head outside for a couple of minutes any clear night and bingo! In early evening you''ll see a sky brimming with bright stars.
Now when I was a kid I always heard about the great Summer Triangle and the great Winter Triangle and most older star charts identify both. But recently more modern star charts now identify yet another geometric figure in winter skies, that of a great Winter Hexagon. Let me show you. O.K., we've got our skies set up for any clear night this month between the hours of 8 and 10 and if you look from overhead toward the south you'll see a bevy of absolutely brilliant stars.
Let's start with the easiest ... the only 3 stars evenly spaced in a row which mark the belt of Orion the Hunter. Now if we take an imaginary arrow and shoot it through the belt down to the left we will land smack dab on the brightest star of any season, the brightest star visible to the naked eye, Sirius, the eye of the Great Dog. This is the brightest star of both the Winter Triangle and the Winter Hexagon. From there we'll draw a line east , to Procyon, the brightest star in the Little Dog and then back to Orion and the reddish star which marks his shoulder, the star called Betelgeuse. Then back to Sirius and voila! There's our winter triangle. Sirius to Procyon, Procyon to Betelgeuse, and Betelgeuse back to Sirius.
Now fortunately Sirius and Procyon are also
2 stars of the Winter Hexagon. To find the 3rd star we draw a
line from Sirius to the brightest star below Orion's Belt, Orion's
bright knee star,Rigel. From Rigel we draw a line to the red eye
of Taurus, Aldebaran, and then we head for the next closest bright
star, Capella in Auriga the Charioteer. Then on to the brightest
star between Capella and Procyon which is the bright star Pollux
of Gemini, the Twins. Then to complete the 6 stars of the Hexagon
over to Procyon. Simple isn't it? Sirius, Procyon and Betelgeuse
make the great Winter Triangle; Sirius, Rigel, Aldebaran, Capella,
Pollux and Procyon, the great Winter Hexagon. 2 wonderfully bright
and chilling pieces of geometry in winter skies and as easy to
find as slipping on ice. I'm Jack Horkheimer, Keep Looking Up!
Horkheimer: Ever wonder why
the stars of winter are the brightest of any season? Well I used
to jokingly say it's because you won't have to spend so much time
out in the cold trying to find them. Indeed, to find the 6 bright
stars that make up the wWnter Hexagon simply look south and start
with the brightest star in the heavens, Sirius, the eye of the
Great Dog, take a right to the knee of Orion, Rigel, then up to
the eye of Taurus, Aldebaran, then way up to Capella in Auriga.
Over to Pollux in Gemini, down to Procyon, the eye of the Small
Dog and back to Sirius. A brilliant but chilling piece of cosmic
geometry. I'm Jack Horkheimer, Keep Looking Up!
* 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
Horkheimer: Greetings, greetings fellow star gazers and this week is a super week for our nearest neighbor planet, the planet named for the goddess of love, Venus. Indeed, this week Venus reaches its greatest brilliancy and is about as high and as bright as you'll ever see it. In fact the last time you saw it this high and bright in evening skies was 8 years ago in 1993 and you won't see it this high and bright in evening skies again until 2009. Let me show you:
O.K., we've got our skies set up facing west just as it starts to get dark out and you'll need no help whatsoever in finding super bright Venus which many people have already mistaken for a UFO this month. It's the same size as our own earth, 8,000 miles wide. And this Wednesday is its official night of greatest brilliancy. Although for all practical purposes it will appear to be almost as bright for the next 2 to 3 weeks.
Now if you want to see something really beautiful, go out at dusk this Sunday evening the 25th and you will see an exquisite 2 day old crescent moon, complete with earth shine hovering half way up from the horizon to Venus. The next night however will be the real winner when a slightly fatter crescent moon will be just off to Venus' left in one of the most dazzling sky pairings of the entire year. Don't miss this! But if you do, Tuesday night the 27th will also be very good when a slightly fatter moon will have moved on and will still make an exquisite coupling with spectacular venus. But the absolutely most beautiful pairing will occur on Monday the 26th. And look now because although Venus is visible for about 3 hours after sunset this week and next, by the 3rd week of March it will be visible for only an hour after sunset and will then soon disappear from evening skies.
But why is Venus so bright you might ask. Well it's a combination of several things. You see Venus is the most reflective planet in our solar system because it is completely covered by white sulphuric acid clouds which reflect over 75% of the sunlight striking it. Plus the last week of this month Venus reaches its closest point to the sun which bathes it with intense sunlight. Plus Venus and earth are extremely close to each other this week, only 40 million miles apart.
You might also ask why does Venus appear so bright in the same place in evening skies every 8 years? Well, because Venus is closer to the sun it travels much faster than our earth. In fact, Venus makes 13 orbits of the sun in exactly the same time our earth makes 8 orbits. So after 8 years Venus and the earth return to the same relative positions ... And thus Venus appears in earth's skies in approximately the same place and brilliancy.
Now for those of you who want
to check out 2 other planets which are still extremely close and
bright to us, on March 1st an almost 1st quarter moon will be
almost between 75,000 mile wide Saturn and 88,000 mile wide Jupiter.
3 fabulous planets. I'm Jack Horkheimer, Keep Looking Up!
Horkheimer: This week Venus
is at its greatest brilliancy and is about as high and bright
as it ever gets. In fact, the last time you saw it this high and
bright in evening skies was 8 years ago in '93 and it won't be
this high and bright in evening skies again until 2009. That's
because Venus makes 13 orbits of the sun in exactly the same time
our earth makes 8 orbits. So after 8 years Venus and earth return
to the same relative positions. And this Monday the 26th we'll
see an absolutely beautiful pairing of the moon and Venus. Don't
miss it because it will be one of the most beautiful cosmic sights
of the year. I'm Jack Horkheimer, Keep Looking Up!
* 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
Horkheimer: Greetings, greetings fellow star gazers. A couple of weeks ago I showed you how to find the wWnter Hexagon and the Winter Triangle, but this week I'd like to give you a closer look at the Winter Triangle because its 3 stars are absolutely wonderful and 2 of them are children's birthday stars.
O.K., We've got our skies set up for any clear night the next couple of weeks between the hours of 8 and 9 p.m. And if you look due south, smack dab right in front of you will be the brightest star visible to the naked eye from planet earth, the star Sirius which marks the eye of the Great Dog Canis Major. Then if we shoot a line up and to the left of Sirius we come to the 2nd star of the Winter Triangle, Procyon, which marks the eye of the Smaller Dog, Canis Minor. Then we can draw a line to the right, above Sirius to the 3rd brightest star of the triangle; the red star Betelgeuse which marks the shoulder of Orion the Hunter. And a line back to Sirius completes our wonderful Winter Triangle.
And wonderful each star is indeed, especially if we compare each one to our sun. For instance, while our own sun is 865 thousand miles wide, Sirius is 1 million, 400 thousand miles wide. Procyon, on the other hand, is even larger than Sirius, 1 1/2 million miles wide. But they're absolutely put to shame by Betelgeuse which is one of those stars which actually varies its size. At its smallest it is 500 times as wide as our sun and at its largest 900 times as wide. Wow!
So why does Sirius appear the brightest of the three if it's actually the smallest? Simple ... it's much closer. Now as you may recall, stars are so far away that we do not speak of their distance in miles. Instead we use the term 'light year'. One light year is the distance light travels in one year, light being the fastest known thing in the universe. Light travels 186 thousand miles a second. So to figure how many miles light travels in one year you have to take all the seconds in one year and multiply that times 186 thousand miles, which equals roughly 6 trillion miles.
Now our sun is so close, only 93 million miles away, that it takes only 8 1/3 minutes for light to travel from it to our earth. So we say it is 8 and 1/3 light minutes away. Sirius, however, is much farther away, 8.6 light years from earth. And Procyon is even farther, 11.4 light years away. Thus as astronomer Fred Schaff says, Procyon and Sirius are the birthday stars of 11 and 9 year olds because when we look at Sirius this winter we are actually seeing the light that left it about 9 years ago when 9 year olds were being born and the light we see from Procyon this winter actually left it 11 years ago when 11 year olds were being born.
So, is Betelgeuse also someone's
birthday star? I hardly think so unless, of course, you were born
525 years ago because when we look at Betelgeuse this winter we
are actually seeing the light that left it in the year 1475, 17
years before Columbus "discovered" the new world. So
get thee outside and witness the wonder of the Winter Triangle.
I'm Jack Horkheimer, Keep Looking Up!
Horkheimer: Whenever we look at the stars we
see them not as they really exist now, but as they existed some
time in the past, depending on how far away they are. We see our
sun as existed 8 and 1/3 minutes ago. The stars of the Winter
Triangle, however are much farther away. We see Sirius, the brightest,
as it existed 9 years ago. So it is the birthday star of 9 year
olds because the light we see this winter left it when 9 year
olds were being born. The light we see from Procyon left it 11
years ago when 11 year olds were being born. So is the 3rd star,
Betelgeuse, also someone's birthday star? Not unless you were
born 525 years ago because the light we see now left it in the
year 1475. I'm Jack Horkheimer, Keep Looking Up!
* 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
![[SmilinJack]](jack1sm.jpg)
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