Saturday: School starts next week so it is time for a little geometry review. Go outside at 10 p.m. tonight with notebook in hand. Ready? A triangle is a polygon with three corners and three line segments as sides. A good example is the summer triangle made up of the bright stars Vega, Deneb and Altair. Vega, the brightest star in the triangle is a little bit west of straight overhead. Deneb is a little bit east of straight overhead and Altair is five fists above the south horizon.
Sunday: Venus is two fists above the east horizon at 5:30 a.m. Mars is four and a half fists above the east-southeast horizon at this time. Nearly 400 years ago, Galileo discovered that Venus goes through phases from new to quarter to full just like our moon does. Thanks to this and Galileo’s many other observations of moons and planets in our solar system, support for an Earth-centered universe was greatly diminished. To commemorate these findings, NASA has made planets and moons this month’s “Hot Topic” for the International Year of Astronomy. For more information, go to http://astronomy2009.nasa.gov/topics.htm and click on September.
Monday: The bright star Capella is just above the north horizon at 8:30 p.m.
Tuesday: “I’m a little teapot, short and stout. The galactic center, I pour it out.” (I’m a Little Teapot, astronomy version, 2009.) Despite its great size and importance, the center of our Milky Way galaxy and its giant black hole remains hidden to the naked eye behind thick clouds of gas and dust. By plotting the orbits if stars near the middle of the galaxy, astronomers have determined that the black hole’s mass is equal to about 4.5 million Suns. While you can see the actual galactic center, you can gaze in the direction of the center by looking to the right of the teapot asterism in the constellation Sagittarius. This point is about one fist above the south-southwest horizon at 9 p.m.
Wednesday: Jupiter is about a half a fist to the lower right of the Moon at 8:30 p.m. Galileo’s discovery of the moons of Jupiter provided strong evidence that objects other than the Earth could have satellites providing more support for a Sun-centered solar system. For more information about Jupiter or observing Jupiter, go to http://astronomy2009.nasa.gov/observe.htm and click on September.
Thursday: It is a good thing Galileo didn’t turn his telescope toward Jupiter tonight from 9:40-11:30 p.m. He would not have seen any moons, people would still think the Earth was at the center of the universe, science would have ground to a halt, and historically important inventions such as music videos and electric can openers would have never been created. “Poppycock”, you say? Evaluate your own feelings tonight. From 9:40 to 11:30 p.m., the four largest moons of Jupiter, Io, Europa, Ganymede, and Callisto will either be in front of or behind Jupiter meaning they can’t be seen from Earth with a small telescope. Jupiter will appear moonless from Earth for over 100 minutes. For more information, go to http://www.skyandtelescope.com/observing/highlights/52543517.html.
Friday: The Ellensburg Rodeo is a “Top-25” rodeo. What does it take to be a “Top-25” star? There are many ways to rank stars. The most obvious way for a casual observer to rank stars is by apparent brightness. The apparent brightness is the brightness of a star as seen from Earth, regardless of its distance from the Earth. Shaula (pronounced Show’-la) is the 25th brightest star in the nighttime sky as seen from Earth. It represents the stinger of Scorpius the scorpion. In fact, Shaula means stinger in Arabic. Shaula has a visual brightness rating of 1.62. Sirius, the brightest star has a visual brightness rating of -1.46. (Smaller numbers mean brighter objects.) The dimmest objects that can be seen with the naked eye have a visual brightness rating of about 6. There are approximately 6,000 stars with a lower visual brightness rating than 6 meaning there are 6,000 stars visible to the naked eye. Shaula is a blue sub-giant star that radiates 35,000 times more energy than the Sun. It is 700 light years away making it one of the most distant bright stars. Shaula is a challenge to find because it never gets more than a half a fist above the horizon. Look for it tonight about a half a fist above the south horizon, a little bit west of due south, at 8:30.
The positional information in this column about stars and planets is typically accurate for the entire week.
Friday, August 28, 2009
Friday, August 14, 2009
The Ellensburg sky for the week of 8/22/09
Saturday: Orion's the hunter. Searching for love in these lonely skies again. (Apologies to my favorite 1980s heavy metal band, Dokken.) Orion is such a prominent constellation, there are many myths about him. Nearly all involve him getting killed. In one myth, he is accidentally killed by his girlfriend Diana, the goddess of the moon and of hunting. She felt so guilty that she repaid her debt by pulling him across the sky each night in her moon chariot. In another myth, Orion is killed by the bite of Scorpius, the scorpion. Obviously, Orion wants to avoid Scorpius in the night sky so he does not get bit again. That is one story of why Orion sets just as Scorpius rises.
Notice that both of these stories have an element of truth. Orion really does cross the sky each night. Orion really does set as Scorpius rises. Many people think a myth is simply a fake story. Instead, a myth is a story used to communicate a message. Myths always have some truth in them. Try to create your own myth about Orion as you see it about two to two and a half fists held upright and at arm’s length above the east-southeast horizon at 5 a.m. The bright reddish star two and a half fists held upright and at arm’s length above the east horizon is Betelgeuse (pronounced Bet'-el-jews). The bright bluish star two fists above the southeast horizon is Rigel.
Sunday: Hit the road Mercury. And don’t you come back no more, no more. For a few weeks, Mercury has been hitting the road and moving away from the Sun in the sky. Today, Mercury is as far away from the Sun as it will get on the evening half of this cycle. This is known as its greatest eastern elongation. Yet, this distance does not translate into good viewing because Mercury will be very low in the sky. Mercury is less than a half a fist above the west horizon at 8:30 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. After it passes in front of the Sun, it will appear in the morning sky by late September.
Monday: Jupiter is two fists above the southeast horizon at 10 p.m.
Tuesday: Pegasus, the winged horse flies across the sky tonight. The horse’s body, represented by a large diamond is between three and five fists above the east-southeast horizon at 11 p.m.
Wednesday: Venus is one and a half fists and Mars is about four fists above the east horizon at 5 a.m. Venus is a little bit north of east and Venus is a little bit south of east.
Thursday: Tonight’s first quarter Moon is in the constellation Scorpius. The bright star Antares is less than a half a fist to the right of the Moon at 10 p.m. In the southern United States, the Moon will pass between the Earth and Antares and block, or occult, Antares.
Friday: Vega, the third brightest star visible from Ellensburg, is nearly straight overhead at 9 p.m.
The positional information in this column about stars and planets is typically accurate for the entire week.
Notice that both of these stories have an element of truth. Orion really does cross the sky each night. Orion really does set as Scorpius rises. Many people think a myth is simply a fake story. Instead, a myth is a story used to communicate a message. Myths always have some truth in them. Try to create your own myth about Orion as you see it about two to two and a half fists held upright and at arm’s length above the east-southeast horizon at 5 a.m. The bright reddish star two and a half fists held upright and at arm’s length above the east horizon is Betelgeuse (pronounced Bet'-el-jews). The bright bluish star two fists above the southeast horizon is Rigel.
Sunday: Hit the road Mercury. And don’t you come back no more, no more. For a few weeks, Mercury has been hitting the road and moving away from the Sun in the sky. Today, Mercury is as far away from the Sun as it will get on the evening half of this cycle. This is known as its greatest eastern elongation. Yet, this distance does not translate into good viewing because Mercury will be very low in the sky. Mercury is less than a half a fist above the west horizon at 8:30 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. After it passes in front of the Sun, it will appear in the morning sky by late September.
Monday: Jupiter is two fists above the southeast horizon at 10 p.m.
Tuesday: Pegasus, the winged horse flies across the sky tonight. The horse’s body, represented by a large diamond is between three and five fists above the east-southeast horizon at 11 p.m.
Wednesday: Venus is one and a half fists and Mars is about four fists above the east horizon at 5 a.m. Venus is a little bit north of east and Venus is a little bit south of east.
Thursday: Tonight’s first quarter Moon is in the constellation Scorpius. The bright star Antares is less than a half a fist to the right of the Moon at 10 p.m. In the southern United States, the Moon will pass between the Earth and Antares and block, or occult, Antares.
Friday: Vega, the third brightest star visible from Ellensburg, is nearly straight overhead at 9 p.m.
The positional information in this column about stars and planets is typically accurate for the entire week.
The Ellensburg sky for the week of 8/15/09
Saturday: It’s a moonless August morning. The first remnant of dawn has not appeared yet. Suddenly, you notice a large softly radiant pyramid of light in the east sky. The base of this ghostly triangle is along the east horizon and the peak stretches two or three fists held upright and at arm’s length above the horizon about two hours before sunrise. Don’t be scared. It’s not really a ghost. It is an effect called the zodiacal light. This light comes from sunlight reflecting off dust grains in our solar system. The effect is the most visible when the band of constellations called the zodiac makes a steep angle with the horizon. You need a clear dark sky with no haze or light pollution to see the zodiacal light. At its brightest, the zodiacal light rivals the light of the central Milky Way. This is one of the best times of year to see the zodiacal light in the morning.
Sunday: There are two “close encounters of the planetary kind” today. At 5 a.m. in the eastern sky this morning, Mars is a half a fist to the upper right of the Moon.
If you don’t like getting early, start! It is a tough economy and you are sleeping in? What’s up with that? Oops. Back to astronomy. There is also an evening encounter to allow you to keep up with your beauty sleep. Mercury and Saturn are about a half a fist above due west at 8:30 p.m. Mercury, the brighter object of the two, is about a thumb width below Saturn.
Monday: Gemini the twins become Gemini the quadruplets this morning. Venus is about a half a fist below the Moon in the eastern sky at 5 a.m. in the constellation Gemini. Pollux and Castor, the two brightest stars in Gemini, are a fist to the left of the Moon and Venus. Pollux is the bottom star and the brighter of the two.
Tuesday: Fomalhaut, the bright star in the Piscis Austrinus, the Southern Fishes, is about one fist above the southeast horizon at midnight. It is the southernmost bright star visible from Ellensburg.
Wednesday: Tonight’s Moon is new. Don’t bother looking for it. The new moon is the phase where the Moon is directly between the Earth and the Sun. Hence the side of the Moon facing Earth is not receiving any sunlight and can not be seen.
Thursday: The brightest star in the nighttime sky is creeping back into the morning sky. Sirius is a half a fist above the east-southeast horizon at 5:30 a.m.
Friday: You may have trouble holding your water at midnight. But not the Big Dipper. The cup of the Big Dipper is facing upward in a water-holding orientation about two fists above the north horizon at midnight.
The positional information in this column about stars and planets is typically accurate for the entire week.
Sunday: There are two “close encounters of the planetary kind” today. At 5 a.m. in the eastern sky this morning, Mars is a half a fist to the upper right of the Moon.
If you don’t like getting early, start! It is a tough economy and you are sleeping in? What’s up with that? Oops. Back to astronomy. There is also an evening encounter to allow you to keep up with your beauty sleep. Mercury and Saturn are about a half a fist above due west at 8:30 p.m. Mercury, the brighter object of the two, is about a thumb width below Saturn.
Monday: Gemini the twins become Gemini the quadruplets this morning. Venus is about a half a fist below the Moon in the eastern sky at 5 a.m. in the constellation Gemini. Pollux and Castor, the two brightest stars in Gemini, are a fist to the left of the Moon and Venus. Pollux is the bottom star and the brighter of the two.
Tuesday: Fomalhaut, the bright star in the Piscis Austrinus, the Southern Fishes, is about one fist above the southeast horizon at midnight. It is the southernmost bright star visible from Ellensburg.
Wednesday: Tonight’s Moon is new. Don’t bother looking for it. The new moon is the phase where the Moon is directly between the Earth and the Sun. Hence the side of the Moon facing Earth is not receiving any sunlight and can not be seen.
Thursday: The brightest star in the nighttime sky is creeping back into the morning sky. Sirius is a half a fist above the east-southeast horizon at 5:30 a.m.
Friday: You may have trouble holding your water at midnight. But not the Big Dipper. The cup of the Big Dipper is facing upward in a water-holding orientation about two fists above the north horizon at midnight.
The positional information in this column about stars and planets is typically accurate for the entire week.
The Ellensburg sky for the week of 8/8/09
Saturday: If the 1970s group The Knack were bigger fans of astronomy, they may have sang: “Oo, my little pretty one, pretty one. When you gonna give me some time, Corona?” The constellation Corona Borealis is a pretty one. Depending on what source you read, the myth associated with the constellation can be happy or sad. Bacchus, Roman god of wine, presented his bride, Ariadne, with a golden crown set with seven diamonds. Some sources say Bacchus tossed the crown in the air out of joy when he married Ariadne. Other sources say he threw the crown into the sky after Ariadne died because it reminded him of her. In either case, his friends among the gods thought the crown was beautiful and hung it in the sky to show it off. You can see if you agree with the Roman gods by looking for Corona Borealis tonight. Seven stars represent the seven diamonds. Look about five and a half fists held upright and at arm’s length above the west horizon or two fists above the bright star Arcturus at 11 p.m. The seven stars form a bowl.
Sunday: Saturn is just about to be obscured by the light of the setting Sun. It is less than a half a fist above the west horizon at 9:15 p.m. Within a few nights, you will not be able to see it. By early October, Saturn will be visible in the morning sky just before sunrise. But, you still have an evening planet to enjoy. Jupiter is a half a fist above the east-southeast horizon at this time.
Monday: Deneb is about seven fists above the east horizon at 10 p.m. When you look at Deneb, you are seeing light that left Deneb about 1,800 years ago.
Tuesday: The Perseid meteor shower peaks late tonight and early tomorrow morning. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about two and a half fists above the northeast horizon at 11 p.m. By 4 a.m., the peak time, this point is about seven fists above the northeast horizon. If you fall asleep or forget to set your alarm, you will be able to observe this shower from midnight to dawn for a few days before and after tonight in about the same location in the sky. The Perseid shower is one of the longest lasting showers. You may be able to see up to 20 meteors per hour in the late night and early morning hours all week. However, the light of the waning gibbous Moon will obscure the dim meteors. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. These meteors are sand to pea-sized bits of rock that fell off of Comet Swift-Tuttle. They are traveling about 40 miles per second as they collide with the Earth and burn up in the atmosphere. For more tips about meteor watching, go to www.skyandtelescope.com/observing/objects/meteors/3304061.html.
Wednesday: Rise and shine and look at the planets at 5 a.m.! Venus, the brightest point of light in the sky, is two fists above the east horizon, a little bit north of east. Mars is three and a half fists above the east horizon, a little bit south of east.
Thursday: This morning’s last quarter Moon is in the constellation Aries the ram.
Friday: Many big city dwellers never see the milky white, nearly continuous band of stars known as the Milky Way. As cities grow and add more lights, it has become harder to see the bulk of the Milky Way galaxy, our home in the universe. But, there are two easy ways to see the Milky Way. The first way is to look in the mirror. You are part of the Milky Way. The second way is to look from due north through the point straight overhead (called the zenith) to due south from 10:30 p.m. to 1 a.m. for the next two weeks. This is the time of year when the Milky Way is highest in the sky and away from the city lights on the horizon.
The positional information in this column about stars and planets is typically accurate for the entire week.
Sunday: Saturn is just about to be obscured by the light of the setting Sun. It is less than a half a fist above the west horizon at 9:15 p.m. Within a few nights, you will not be able to see it. By early October, Saturn will be visible in the morning sky just before sunrise. But, you still have an evening planet to enjoy. Jupiter is a half a fist above the east-southeast horizon at this time.
Monday: Deneb is about seven fists above the east horizon at 10 p.m. When you look at Deneb, you are seeing light that left Deneb about 1,800 years ago.
Tuesday: The Perseid meteor shower peaks late tonight and early tomorrow morning. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about two and a half fists above the northeast horizon at 11 p.m. By 4 a.m., the peak time, this point is about seven fists above the northeast horizon. If you fall asleep or forget to set your alarm, you will be able to observe this shower from midnight to dawn for a few days before and after tonight in about the same location in the sky. The Perseid shower is one of the longest lasting showers. You may be able to see up to 20 meteors per hour in the late night and early morning hours all week. However, the light of the waning gibbous Moon will obscure the dim meteors. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. These meteors are sand to pea-sized bits of rock that fell off of Comet Swift-Tuttle. They are traveling about 40 miles per second as they collide with the Earth and burn up in the atmosphere. For more tips about meteor watching, go to www.skyandtelescope.com/observing/objects/meteors/3304061.html.
Wednesday: Rise and shine and look at the planets at 5 a.m.! Venus, the brightest point of light in the sky, is two fists above the east horizon, a little bit north of east. Mars is three and a half fists above the east horizon, a little bit south of east.
Thursday: This morning’s last quarter Moon is in the constellation Aries the ram.
Friday: Many big city dwellers never see the milky white, nearly continuous band of stars known as the Milky Way. As cities grow and add more lights, it has become harder to see the bulk of the Milky Way galaxy, our home in the universe. But, there are two easy ways to see the Milky Way. The first way is to look in the mirror. You are part of the Milky Way. The second way is to look from due north through the point straight overhead (called the zenith) to due south from 10:30 p.m. to 1 a.m. for the next two weeks. This is the time of year when the Milky Way is highest in the sky and away from the city lights on the horizon.
The positional information in this column about stars and planets is typically accurate for the entire week.
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