STAR GAZER
THE INTERNATIONAL EDITION
 |
 |
 |
James: Hey there star gazers I'm James Albury
from the Kika Silva Pla Planetarium at Santa Fe College in Gainesville
Florida and I'll be your guide to the sky this month on Star Gazer.
Usually this first week of August I would be telling you to get
ready for the Perseid Meteor Shower which will peak this year
on Friday night August 12th through Saturday morning the 13th
but this meteor shower will not be very good this year. The meteors
will be as plentiful as they usually are but the sky will be so
bright because of the full Moon that you won't get to see very
many of them. This is not a guarantee of nothing but it is the
way to bet. The Moon will be full at 2:57 Saturday afternoon,
Eastern Time. Which means that by the time the Moon changes its
phase and gets out of the sky, in about 4 to 5 days, the Perseid
Meteor Shower will be over for this year. So next Friday night
you may see some Perseids if you get away from city lights but
not as many as you'd see if the Moon wasn't in the way.
The Perseid Meteor Shower is one of the most easily observed meteor showers because it occurs during the warm, balmy nights of August. The second best Meteor Shower is in early December, Brrrrr! Meteor Showers happen when the Earth runs into the stream of debris left in the path of a comet as it orbits the Sun. In this case the comet is named Comet Swift-Tuttle, after two astronomers, Lewis Swift and Horace Tuttle who are credited with discovering it. Since the Earth's orbit is pretty regular and repeats much the same way each year we come back to the same spot in space at the same time every year. This is why the Perseid Meteor Shower repeats at the same time each year. It's not that the comet comes back each year at this time. The most recent visit by Comet Swift-Tuttle was in 1992 and we're not expecting it again for 135 years. But next year, August 12, 2012, the Perseid Meteor Shower will happen again because debris from Comet Swift-Tuttle has been spread all long its orbital path and next year the Perseid Meteor Shower should be better since next August 12th the Moon will be a waning crescent and will not rise until after midnight. Now for something we can see next week.
Get out after sunset, any night next week, look west and you'll see several bright points of light, some stars and one non-star. Let's start with the brightest light that you're likely to see first. Twinkle, twinkle little star about half way up from the horizon you'll spot a very bright star, Arcturus. Arcturus is not a run of the mill star. It is the third brightest star we can see from Earth and it's over 200 times brighter and about 26 times the diameter of our Sun. An easy way to remember the name of Arcturus is to look for the Big Dipper in the northwest and extend the arc of its handle and you'll come to Arcturus. Arc to Arcturus, remember? Below Arcturus closer to the horizon you'll spot a pair of somewhat dimmer lights. The light to the left is the star Spica and to its right is the ringed planet Saturn. Spica is a hot blue multiple star whose light has taken over 260 years to get here while the light you see from Saturn only needs about 85 minutes to make the trip from Saturn because Spica is nearly 2 million times farther away. This is a great opportunity to see how stars and planets differ in how they look in the sky; stars will twinkle, while planets won't.
Stars look like dimensionless points of light
since they are so far away while planets actually look bigger
because they are so much closer. The twinkling of a star is really
caused by movement in the layers of air that the light from the
star has to pass through on its way to your eye. Planets don't
usually twinkle because their image is not disrupted as much by
this movement of the air. You don't hear anybody singing twinkle,
twinkle little planetSo take a look at Spica and see if you can
see it flash and change color and then compare Spica to Saturn
off to its right. Then look at Arcturus, higher in the sky and
see if it's twinkling. So remember that the Perseid Meteor Shower
will probably fizzle this year but Spica, Saturn and Arcturus
will dazzle in the early evening. Get outside my friends and keep
looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
Version|
|
|
|
|
James: Hey there star gazers. The Perseid Meteor Shower which will peak this year on Friday night August 12th through Saturday morning will not be very good this year because the full Moon will get in the way and you won't get to see very many of them. This is not a guarantee of nothing, but it is the way to bet. Now for something we can see next week. Get out after sunset, any night next week, look west and you'll see several bright points of light, some stars and one non-star. About half way up from the horizon you'll spot a very bright star, Arcturus. Below Arcturus, closer to the horizon you'll spot a pair of somewhat dimmer points of light. The light to the left is the star Spica and to its right is the ringed planet Saturn. So remember that the Perseid Meteor Shower will probably fizzle this year but Spica, Saturn and Arcturus will dazzle in the early evening. Get outside my friends and 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
|
|
|
|
James: Hey there star gazers I'm James Albury from the Kika Silva Pla Planetarium at Santa Fe College in Gainesville Florida and I'll be your guide to the sky this month on Star Gazer. If you know when and where to look you can get a preview of the brightest stars of winter in the sultry days of August. Plus the Moon pays a visit to two morning planets to close out the month. Let me show you.
O.K., we've got our skies set up for this weekend Saturday August 20th about 45 minutes before sunrise facing east where you'll see several bright stars covering a huge area from east to southeast. In fact almost due east you'll see winter's super bright star Procyon, which marks the eye of Orion the Hunter's little dog. And to its right just above the southeast horizon is the brightest star we can see from Earth Sirius, which marks the eye of Orion's big dog. And of course right above Sirius the unmistakable three stars evenly spaced in a row which mark the belt of winter's most famous constellation Orion himself, his two knee stars to the right and his two shoulder stars to the left.
And directly above his shoulder stars Aldebaran the reddish star which marks the eye of Taurus the Bull. And to Taurus' left Capella the brightest star of winter's Auriga the Charioteer. And directly below him Castor and Pollux the two brightest stars of Gemini the Twins. So even though nights may still be hot and sultry where you live at the end of August, every August if you get out just before sunrise you can see all of the brightest stars of winter above the eastern horizon. But this year something new has been added because up and to the right of Orion is a very bright spot of light in your morning sky. In fact you can use the belt of Orion to get you started on your way to find it.
Take the three belt stars of Orion and shoot an arrow to the right through those belt stars and head towards the south and you'll come to the king of the planets Jupiter. Jupiter is slowly plodding eastward among the stars but it's about to stop at the end of August and then back up and retrace its path westward until Christmas time. This backing up marks the best time to observe Jupiter because it will be at its closest to us in October at what we call opposition. This backward movement is called retrograde motion and was quite a puzzle for ancient astronomers. Jupiter does nothing quickly. It takes about 12 Earth years for Jupiter to orbit the Sun one time. One exception to this is the family of moons that orbits Jupiter. They do move quickly in their circuits around Jupiter and you can see them move across the face of Jupiter in just a few hours.
To the right of Castor and Pollux you might notice an additional dim orangeish light, which usually isn't there. The red planet Mars is about 14 degrees to the right of Pollux. Mars is not very bright right now because it's on the other side of the solar system from us. Mars now is actually about twice as far away as we are from the Sun. We will steadily close in on Mars and approach it every day until March of 2012. Some of you may remember when Mars was at its closest to Earth in over 50,000 years back in August of 2003. Well this is nothing like that. Mars is now only 2% as bright as it was back in August of 2003. You may see a garbage story on the internet about Mars being as big as the Moon over the next few weeks but now you know the real story. You can find Mars though it will be a challenge. But never fear our old friend the Moon will come along soon and help show you the way.
And if you're one of those who never really
knows for sure whether or not you've found a planet, well just
use the Moon as a finder. On Saturday August 20th a 21 day old
waning gibbous Moon will be parked very close to Jupiter and over
the next five days will step across the sky and end up helping
you to locate Mars. On Thursday August 25th a 25 day old waning
crescent Moon will be just three degrees to the right of Mars.
All of winter's bright stars visible in the east just before sunrise
at August's end plus two planets. Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
Version|
|
|
|
|
James: You can get a preview of the brightest
stars of winter in the sultry days of August. Plus the Moon visits
two morning planets. Let me show you. We've got our skies set
up for Saturday August 20th about 45 minutes before sunrise facing
east where you'll see winter's super bright star Procyon, Orion
the Hunter's little dog. And to its right is Sirius, the eye of
Orion's big dog. And right above Sirius the unmistakable Orion
himself, and directly above him Aldebaran the eye of Taurus the
Bull. And to Taurus' left Capella the brightest star of Auriga
the Charioteer. And directly below him Castor and Pollux the two
brightest stars of Gemini the Twins. On August 20th a gibbous
Moon will be very close to Jupiter and on August 25th a waning
crescent Moon will be just to the right of Mars. All of winter's
bright stars visible in the east just before sunrise at August's
end plus two planets. 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
|
|
|
|
James: Greetings fellow stargazers! I'm James
Albury from the Kika Silva Pla Planetarium at Santa Fe College
in Gainesville Florida and I'll be your guide to the sky this
month on Star Gazer. Have you ever noticed that sometimes you
can see the Moon at night but not in the morning? And sometimes
you can see the Moon in the morning but not at night? I can explain,
with a little help from the Moon
Next week you can best catch the Moon in the morning skies. We have our skies set up for Saturday August 20th at 5:00 am looking high in the southeast. You can't miss the third quarter Moon just above the second brightest object in the pre-dawn sky - the stately planet Jupiter. This conjunction between the Moon and Jupiter is only temporary. Every day the Moon shifts about 13 degrees across the background stars -toward the east. That means that if we look at the sky the very next morning, same place, same time, the Moon will appear about 13 degrees away from Jupiter. The next morning, Monday August 22nd, the Moon will be another 13 degrees farther east and shine between the Pleiades star cluster and the face of Taurus the bull. This apparent movement is caused by the Moon's orbit around the Earth. It takes the Moon 27.3 days to orbit the Earth and return to a similar place among the stars. So 27.3 days after August 20th, September 16, the Moon will be close to Jupiter again. To complete a full orbit in 27.3 days it moves pretty fast - about 1 kilometer per second through space. And to cover all 360 degrees of the orbit in that time well, this Moon motion averages out to about 13 degrees per day. Where the Moon lies in its orbit tells you the best time of day to view it.
When the Moon is new, it rises and sets with the Sun. It's up during the day and you just can't see it. If you wait a day or two you can see a waxing crescent Moon in the west just after the Sun sets. You can see a waxing and first quarter Moon after sunset. The first quarter Moon rises about 6 hours after the Sun and the Sun sets 6 hours before the Moon. So you can see the Moon right after it gets dark. The classic, full Moon rises as the Sun sets because the Moon has arced around in its orbit to the opposite side of the sky from the Sun. You might see this if you're driving east at Sunset. As the Sun goes down in the west, a big full Moon rises on the opposite horizon. In the morning it's the waning Moon that you see - sometimes even after the Sun rises. During a third quarter Moon, the Moon is three quarters of its way around the Earth and heading back to new Moon. The Sun, Earth and Moon make a nice 90 degree angle in the sky with the Moon rising about 6 hours before the Sun. Once you get good at recognizing the Moon phase and its position in the sky, you can even start telling time with just the Moon.
Let's get back to the sky to watch where the
Moon goes next. On Tuesday August 23rd the Moon is most definitely
waning, or getting smaller, and will be a waning crescent. And
it has shifted closer to that most famous constellation, Orion
the hunter. There he is right below the Moon with his belt of
three stars and his upraised arms. It almost looks like he's about
to catch the Moon! The next morning, Wednesday August 24th, the
Moon has continued in its orbit around the Earth and shifted another
13 degrees closer to the eastern horizon. And now, instead of
catching the Moon, Orion looks like he's decided to whack it with
his club. Don't worry. He'll miss it because the next morning,
Thursday August 25th, a slimmer crescent Moon will cozy up next
to a planet of a redder color, Mars. Mars is much fainter than
Jupiter right now even though it's so much closer to us. In fact,
Mars is more than twice as close to Earth right now compared to
Jupiter. But at 1/20th the diameter of Jupiter, Mars can't compete
with Jupiter's brilliance. So, watch the Moon move through _ of
its orbit this week and it will lead you from giant Jupiter on
August 20th to rusty Mars on August 25th. And in between, it dodges
the Seven Sisters, the Bull, and Orion's bat. Keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
Version|
|
|
|
|
James: Early risers, have I got a treat for you.
The Moon will leave Jupiter behind, go between the arms of Orion
and then cozy up next to Mars in the morning sky. Let me show
you. Let's start with Saturday August 20th at 5:00 am looking
high in the southeast. There is the third quarter Moon above brilliant
Jupiter. You can't miss these two brightest objects in the pre-dawn
sky. The next morning, same time, same place the Moon will move
steadily away from Jupiter. Monday morning brings the Moon near
the Pleiades star cluster. On Tuesday the Moon moves toward the
outstretched arms of the constellation Orion and Wednesday Orion
bats the Moon with his club. Finally on the morning of Thursday
August 25th, lower in the east, a slim crescent Moon comes to
within 3 degrees of a dimmer, but decidedly redder planet, Mars.
The Moon will lead you from planet to shining planet. I'm James
Albury reminding you to 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|
|
|
|
James: Greetings fellow stargazers! I'm James Albury from the
Kika Silva Pla Planetarium at Santa Fe College in Gainesville
Florida and I'll be your guide to the sky this month on Star Gazer.
September's almost here and next week we'll see the Moon have
a close encounter with both a star and a planet and we'll also
see the second largest planet in our solar system say farewell
to a starry companion. Wondering what I'm talking about? Here,
let me show you!
Alrighty! I have our sky set for just after sunset facing west. Directly above the western horizon you'll see the familiar triangle of bright lights that we've been talking about since April. The bright stars, Arcturus and Spica and the ringed planet, Saturn. You can find the trio by following the handle of the Big Dipper toward the star Arcturus, and then trace another line from Arcturus down to Spica. Just to Spica's right is the planet Saturn. On Wednesday August 31st, you'll see the Moon form a neat little triangle with Spica and Saturn. Then the next day, Thursday September 1st, the Moon, Spica and Saturn will form a nearly straight line in the sky. And all of this happens just after Sunset, so you should have no trouble seeing it from wherever you live.
If you've been watching Saturn over the past few months, you've noticed it's appeared very close to a little star called Porrima. Porrima is the third brightest star in the zodiacal constellation of Virgo the virgin. Porimma is actually a binary star system; that is two stars that orbit each other. Both stars are a little bigger than our Sun, they're yellow-white in color and it takes them almost 169 years to orbit each other one time. The stars are usually far enough apart, that in a small telescope, you can actually see them individually. Unfortunately, the way the stars appear right now, it's very difficult to see any separation between them. You'll have to wait until 2020 for the stars to be far enough apart to see them individually using a small telescope.
The Porrima star system is 38.5 light years away. That means the light we see coming from the Porrima star system left back in 1973. So, when we look at this dancing pair of stars, we are actually looking back in time. So, if you think about it, we won't actually see what the stars look like right now until 2049. Wow! All this year, Saturn has appeared very close to Porrima. Saturn is what the Greeks referred to as a wandering star. And as the nights pass, you'll notice that Saturn is getting farther and farther away from Porrima and heading quickly toward Spica, the brightest star in Virgo. This rapid change in Saturn's position is caused by our movement around the Sun.
Imagine our solar system is a giant race track, and all the planets are moving around this track in the same direction but at different speeds. Since we're closer to the Sun, the Sun's gravity has a stronger pull on us, making us travel much faster around the Sun than Saturn. Believe it or not, the Earth is moving at over 66,000 mph around the Sun. That's over 18 miles every second! At that speed, you could travel from New York City, New York to Los Angeles, California in only two and a half minutes! So in effect, we're leaving Saturn behind and in a few months we'll be on the opposite side of the solar system from Saturn. As the Earth travels around the Sun, Saturn will appear to move faster in the sky in the direction of Spica, thus moving away from Porrima. Then after we come around the Sun on the other side, Saturn will appear to loop back to where it was in the sky before, but this time Saturn will be 12 degrees further east in the sky than where we left it. That's because while we were "rounding the far turn", Saturn was still poking along at a modest 21,676 miles per hour, or 6 miles per second. So Saturn and Porrima are going to be saying farewell to one another and won't be this close in the sky again until winter 2040, Alrighty, well out under the stars with you my friends and see this pair while you can and remember, whatever you do, keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
Version|
|
|
|
|
James: September's almost here and next week we'll
see the Moon have a close encounter with both Spica and Saturn,
and we'll also see Saturn say farewell to a starry companion.
Wondering what iIm talking about? Here, let me show you! Alrighty!
I have our sky set for just after sunset facing west. Directly
above the western horizon you'll see the familiar triangle of
bright lights, Arcturus and Spica and the ringed planet, Saturn.
If you've been watching Saturn over the past few months, you've
noticed it's appeared very close to a little star called Porrima.
As the Earth travels around the Sun, Saturn will appear to move
quickly in the sky in the direction of Spica. On Wednesday august
31st, you'll see the Moon form a neat little triangle with Spica
and Saturn. Then the next day, Thursday September 1st, the Moon,
Spica and Saturn will form a straight line in the sky. 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
|
|
|
|
James: Hey there star gazers I'm James Albury from the Kika Silva
Pla Planetarium at Santa Fe College in Gainesville Florida and
I'll be your guide to the sky this month on Star Gazer. Next week
there is a great chance to see the most elusive of the naked eye
planets, Mercury in the early dawn. Plus do you know that every
Labor Day weekend three very bright stars, will make a giant triangle
shine overhead? Let me show you how to find Mercury and the Triangle
this and every Labor Day weekend.
Simply go outside between 9 and 10 p.m. your local time any Labor Day weekend and look straight up almost overhead and you will see three extremely bright stars which if we connect with lines make a huge stellar triangle which is traditionally called the Summer Triangle because every year these three stars can be seen rising over the eastern horizon in early evening at the beginning of summer. But since the stars change their position with each season by the time September rolls around this triangle has changed its position so that in early evening it is almost directly overhead and makes an almost perfect must-see Labor Day tradition.
Now each star belongs to a separate constellation. So not only do we have three wonderful stars we have three equally wonderful constellations. The brightest star is Vega and it belongs to the small constellation Lyra the Harp. The second brightest is Altair in a much larger constellation called Aquila the Eagle. And the dimmest of the three is Deneb which marks the tail of a huge constellation called Cygnus the Swan. Now if we compare each of these three stars with the star we call our Sun you'll be in for a big surprise. Our Sun is the closest star only 8 1/3 light minutes away, which means it takes its light 8 1/3 minutes to reach us, so we see it not as it actually exists now but as it existed 8 1/3 minutes ago. Altair is the closest triangle star and is 17 light years away, which means that it takes its light 17 years to reach us. So we see it not as it exists this Labor Day weekend but as it existed 17 years ago. Wow!
Vega is slightly farther, 25 light years away, which means that it takes its light 25 years to reach us so we see it as it existed 25 years ago. Wow again! Deneb however is so incredibly far away, 1500 light years, that it takes its light 1500 years to reach us so we see it as it existed 1500 years ago! Super wow! And talk about size and brightness! Altair is 1 1/2 times the diameter of our almost 1 million mile wide Sun and 9 times brighter. Vega however is 2 1/2 times the diameter of our Sun and is 58 times brighter. But you ain't seen nothing yet because Deneb is a super 116 times as wide as our Sun and 60,000 times brighter! In fact if it were as close as Vega and Altair it would be the brightest star in the night sky.
Meanwhile in the morning sky there is another triangle and a special celestial visitor that makes it worth your while to get up early to star gaze. The tiny planet Mercury is notoriously difficult to find, let alone observe it. Mercury orbits closer to the Sun than any other planet so Mercury is never visible in a dark night sky. Get out around 5 a.m. Monday the 5th and look southeast and bingo it's winter time. Lots of our favorite winter stars are making their return. Let's focus on just three bright ones for now. Sirius, Procyon and Betelgeuse make up the Winter Triangle. Down to their left and low on the horizon will be a bright pinkish spot of light and that's the planet Mercury. Below Mercury is a bright star, Regulus the heart of Leo the Lion. If you watch over the next few days Regulus will seem to rise up to meet Mercury on the morning of Sept. 9th when they will be only 1/2of a degree apart.
So there you have it. Three bright stars forming
a giant triangle almost overhead in early evening every Labor
Day weekend. And a bright triangle of the winter season to come,
in the early morning and joined this year by the most elusive
of the planets. Happy Labor Day and keep looking up!
How did you like this episode?
Please give us your comments. (Click
Here)
Version|
|
|
|
|
James: Want to start a cosmic Labor Day tradition?
Then look almost overhead at 9 p.m and you'll see three very bright
stars in three constellations, which make up a Great Triangle.
Altair in Aquila the Eagle is only 16 light years away Vega, the
brightest in Lyra the Harp, is 25 light years away. But Deneb
the dimmest in Cygnus the Swan, is dim only because it is 1500
light years away. This great Summer Triangle is overhead at night
every Labor Day weekend. Then get out around 5 a.m. Monday the
5th and look southeast and bingo it's Sirius, Procyon and Betelgeuse,
the Winter Triangle. Down to their left and low on the horizon
will be a bright pinkish spot of light and that's the planet Mercury.
Happy Labor Day and 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]