Saturday: If the National Enquirer was around in Galileo’s day, it may have featured the headline: “Saturn has love handles; Opis leaves him for a much thinner Mars”. When Galileo first observed Saturn through a telescope, he reported objects that looked like bulges on either side of Saturn’s midsection. He was actually seeing Saturn’s rings through less than ideal optics. Go to http://astronomy2009.nasa.gov/observe.htm for more information about Saturn. Go to three and a half fists held upright and at arm’s length above the southeast horizon at 10 p.m. to see Saturn.
Sunday: March’s “Hot Topic” for the International Year of Astronomy is observing at night… and in the day. Technology has expanded the amount of information astronomers can learn from observing the sky. Up until the mid 1900s, we studied the sky using a very narrow portion of the electromagnetic spectrum – visible light waves. It was like studying music by listening only to notes of medium pitch. The invention of the radio telescope opened up a new source of information, long wavelength radiation. It also opened a new time to observe the sky – the day time. Radio waves from outer space are not blocked by the sunlit sky like visible light from outer space is. Since then, astronomers have started gathering gamma ray, x-ray, ultraviolet, infrared, and microwave radiation. Finally, the entire symphony rather than a few notes. But technology has also negatively impacted our view of the nighttime sky through light pollution. The dim light of a distant galaxy is facing more and more competition from businesses that use inefficient lighting that lights the sky as much as it lights the ground. Many communities, including Ellensburg, have passed or are working on ordinances to reduce this costly and sky-robbing stray lighting. Go to http://astronomy2009.nasa.gov/topics.htm for more information about the March “Hot Topic”.
Monday: It’s getting dark. The last remnant of twilight has disappeared. Suddenly, you notice a large softly radiant pyramid of light in the western sky. The base of this ghostly triangle is along the west horizon and the peak stretches two or three fists above the horizon. It is 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.
Tuesday: Tonight’s first quarter moon is in the constellation Taurus the bull.
Wednesday: “The crow rises in the southeast” said spy number one. “I’m sorry. I don’t recognize that code” replied spy number two. Spy one exclaimed, “That’s because it’s not a code, you idiot. I’m talking about the constellation Corvus the crow.” This is very bad spy movie dialogue to remind you that Corvus had a very bad life. According to one myth, Corvus brought the god Apollo the news that his girlfriend was seeing someone else. In a classic case of punishing the messenger, Apollo turned the formerly beautifully colored crow black. The box-shaped Corvus is one fist above the southeast horizon at 11 p.m.
Thursday: Venus is two fists above due west at 7 p.m.
Friday: Jupiter is less than a half a fist above the east-southeast horizon at 6 a.m.
The positional information in this column about stars and planets is typically accurate for the entire week.
Monday, February 23, 2009
Thursday, February 19, 2009
The Ellensburg sky for the week of 2/21/09
Saturday: In this, the 200 anniversary of the year of his birth, let’s remember Abraham Lincoln: 16th president, person on the penny, and astronomer. Astronomer? Well, maybe not an astronomer, but someone who used observational evidence from the sky to solve a problem. In 1858, Lincoln defended Duff Armstrong, a family friend who was accused of murder. The prosecution thought they had a strong case because their primary witnesses claimed to have observed the killing by the light of the nearly full moon. Let’s listen in on the trial courtesy of the 1939 film, Young Mr. Lincoln.
Lincoln: How’d you see so well?
Witness: I told you it was Moon bright, Mr. Lincoln.
Lincoln: Moon bright.
Witness: Yes.
(Dramatic pause as Lincoln reaches for something)
Lincoln: Look at this. Go on, look at it. It’s the Farmer’s Almanack. You see what it says about the Moon/ That the Moon… set at 10:21, 40 minutes before the killing took place. So you see it couldn’t have been Moon bright, could it?
Lincoln used the known information about Moon rise and set times for August 29, 1858 as evidence in a trial. You may confirm Lincoln’s findings on the Moon set time by going to http://aa.usno.navy.mil/data/docs/RS_OneYear.php, the US Naval Observatory website, and filling out Form A. For more information about Lincoln’s “almanac trial”, go to http://media.skyandtelescope.com/documents/Almanac_Trial.pdf.
Sunday: The region in the low southeastern sky around the Moon is crowded with three planets this morning. Mercury is just to the left of the Moon. To the left of Mercury is the brightest of the three planets, Jupiter. Mars is to the lower left of Jupiter. You may need binoculars to see all three at 6:30 a.m. If this morning is cloudy, keep inspecting this part of the dawn sky for the next few days. The Moon will have moved away but the planets will remain clumped together.
Monday: Comet Lulin, discovered in July 2007, is just below Saturn tonight. Grab your binoculars and look three fists held upright and at arm’s length above the southeast horizon at 10 p.m. Saturn is the brightest point of light in that region of the sky. Comet Lulin will be an elongated smudge just below it.
Tuesday: 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 cannot be seen.
Wednesday: Sirius, the brightest star in the nighttime sky, is two and a half fists above the south horizon at 9 p.m.
Thursday: The bright star Arcturus is two and a half fists above due east at 11 p.m.
Friday: Venus is about a finger’s width to the right of the young crescent Moon. At 7 p.m., they are two fists above the west horizon. Venus is in the western evening sky the entire week.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Lincoln: How’d you see so well?
Witness: I told you it was Moon bright, Mr. Lincoln.
Lincoln: Moon bright.
Witness: Yes.
(Dramatic pause as Lincoln reaches for something)
Lincoln: Look at this. Go on, look at it. It’s the Farmer’s Almanack. You see what it says about the Moon/ That the Moon… set at 10:21, 40 minutes before the killing took place. So you see it couldn’t have been Moon bright, could it?
Lincoln used the known information about Moon rise and set times for August 29, 1858 as evidence in a trial. You may confirm Lincoln’s findings on the Moon set time by going to http://aa.usno.navy.mil/data/docs/RS_OneYear.php, the US Naval Observatory website, and filling out Form A. For more information about Lincoln’s “almanac trial”, go to http://media.skyandtelescope.com/documents/Almanac_Trial.pdf.
Sunday: The region in the low southeastern sky around the Moon is crowded with three planets this morning. Mercury is just to the left of the Moon. To the left of Mercury is the brightest of the three planets, Jupiter. Mars is to the lower left of Jupiter. You may need binoculars to see all three at 6:30 a.m. If this morning is cloudy, keep inspecting this part of the dawn sky for the next few days. The Moon will have moved away but the planets will remain clumped together.
Monday: Comet Lulin, discovered in July 2007, is just below Saturn tonight. Grab your binoculars and look three fists held upright and at arm’s length above the southeast horizon at 10 p.m. Saturn is the brightest point of light in that region of the sky. Comet Lulin will be an elongated smudge just below it.
Tuesday: 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 cannot be seen.
Wednesday: Sirius, the brightest star in the nighttime sky, is two and a half fists above the south horizon at 9 p.m.
Thursday: The bright star Arcturus is two and a half fists above due east at 11 p.m.
Friday: Venus is about a finger’s width to the right of the young crescent Moon. At 7 p.m., they are two fists above the west horizon. Venus is in the western evening sky the entire week.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Wednesday, February 11, 2009
The Ellensburg sky for the week of 2/14/09
Saturday: According to Greek mythology, the beautiful princess Andromeda was chained to a rock next to the ocean. Cetus the sea monster was about to devour her in order to punish her family. It seemed that all was lost. But, along came the great warrior Perseus, fresh off his defeat of the evil Gorgon, Medusa. The only similarity between Andromeda and Medusa was that Andromeda caused people to stand still and stares at her beauty while Medusa turned people to stone because of her ugliness. (And, you thought you looked bad in the morning.) Even though Perseus’ standing as the son of King Zeus and the slayer of Medusa was probably enough to win Andromeda under normal circumstances, Andromeda’s impending death-by-sea-monster was not a normal circumstance. So, Perseus drove his sword into the sea monsters neck and killed it. In a little known addendum to the story, Perseus carved “Percy (heart symbol) Andi” in the rock, thus originating the use of the heart symbol as a substitute for the word “love”.
You can find these lovers in the sky this Valentine’s Day. Just remember it is rude stare – and you never know when you might turn to stone. First, find the Great Square of Pegasus at 7 p.m. between one and a half and three and a half fists held upright and at arm’s length above the west horizon. The lowest star in Andromeda is the top star in the square. This represents Andromeda’s head. Perseus is at her feet, nearly straight overhead. Mirphak, the brightest star in Perseus is about eight fists above the west horizon. Perseus’ body is represented by the line of stars to the left and right of Mirphak.
Sunday: Comet Lulin, discovered in July 2007, is just above the bright star Spica for the next three mornings. Grab your binoculars and look two and a half fists above the southwest horizon at 6 a.m. Spica is the brightest star in that region of the sky. Comet Lulin will be an elongated smudge just above it.
Monday: Saturn is almost two fists above the east horizon at 9 p.m.
Tuesday: The bright star Antares is about a finger’s width to the left of the Moon at 6:30 a.m. They are due south at this time.
Wednesday: “Happy Birthday to you. Happy Birthday to you. Happy Birthday dear Pluto. Happy Birthday to you.” Clyde Tombaugh discovered Pluto, the solar system object formerly known as a planet, on this day in 1930.
Thursday: The calendar may say February, but the late night sky is starting to say “summer triangle”. Vega, the brightest star in the summer triangle rises at 10:30 p.m. By midnight, it is a little less than one fist above the northeast horizon. The Summer Triangle is a set of three stars that is visible high throughout most of the night in the summer sky.
Friday: Three planets crowd the morning twilight sky. From lower left to upper right, Mars, Jupiter and Mercury are less than a half a fist above the east-southeast horizon, just ahead of the rising Sun. You may need binoculars to pick them out of the glare.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
You can find these lovers in the sky this Valentine’s Day. Just remember it is rude stare – and you never know when you might turn to stone. First, find the Great Square of Pegasus at 7 p.m. between one and a half and three and a half fists held upright and at arm’s length above the west horizon. The lowest star in Andromeda is the top star in the square. This represents Andromeda’s head. Perseus is at her feet, nearly straight overhead. Mirphak, the brightest star in Perseus is about eight fists above the west horizon. Perseus’ body is represented by the line of stars to the left and right of Mirphak.
Sunday: Comet Lulin, discovered in July 2007, is just above the bright star Spica for the next three mornings. Grab your binoculars and look two and a half fists above the southwest horizon at 6 a.m. Spica is the brightest star in that region of the sky. Comet Lulin will be an elongated smudge just above it.
Monday: Saturn is almost two fists above the east horizon at 9 p.m.
Tuesday: The bright star Antares is about a finger’s width to the left of the Moon at 6:30 a.m. They are due south at this time.
Wednesday: “Happy Birthday to you. Happy Birthday to you. Happy Birthday dear Pluto. Happy Birthday to you.” Clyde Tombaugh discovered Pluto, the solar system object formerly known as a planet, on this day in 1930.
Thursday: The calendar may say February, but the late night sky is starting to say “summer triangle”. Vega, the brightest star in the summer triangle rises at 10:30 p.m. By midnight, it is a little less than one fist above the northeast horizon. The Summer Triangle is a set of three stars that is visible high throughout most of the night in the summer sky.
Friday: Three planets crowd the morning twilight sky. From lower left to upper right, Mars, Jupiter and Mercury are less than a half a fist above the east-southeast horizon, just ahead of the rising Sun. You may need binoculars to pick them out of the glare.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Thursday, February 5, 2009
The Ellensburg sky for the week of 2/7/09
Saturday: Are you scared of snakes? Then don’t look due east at 6:30 p.m. The pentagon-shaped head of Hydra the water snack is about one fist held upright and at arm’s length above the east horizon. And, this is no ordinary water snake. It is the largest constellation in the sky, more than twice the size of Orion. Hydra’s tail does not rice until after midnight.
Sunday: Tonight and tomorrow morning’s full moon is in the constellation Leo the lion. Because February is typically the snowiest month, some Native American tribes in the northeastern United States called the full moon in February the Full Snow Moon. Some tribes referred to how the harsh winter conditions affected their food gathering ability by calling the February full moon the Full Hunger Moon. The name Full Hunger Moon is especially appropriate this month because Leo the lion seems to be stalking the moon throughout the night to hunt it down for food.
Monday: Regulus, the brightest star in the constellation Leo the lion is about a thumb width to the left of the Moon at 7 p.m. They are both low on the eastern horizon.
Tuesday: Hydra is not the only long, squiggly constellation in the sky. Draco the dragon wraps around the cup of the little dipper. The head of the dragon is one fist above due north at 7:30 p.m. Eltanin, the brightest star in the constellation, is at one corner of the trapezoid-shaped head of Draco. Eridanus the river starts next to Rigel, the bright star in the lower right corner of Orion, and meanders down below the south horizon. Rigel is three and a half fists above due south at 7:30 p.m. That means at 7:30 tonight, there are long, squiggly constellations in the lower northern, southern and eastern sky.
Wednesday: Saturn is less than a fist above the Moon at 6 a.m. They are about two fists above the west-southwest horizon.
Thursday: In the past decade or so, astronomers have discovered 339 planets orbiting stars other than our Sun. All of these exoplanets, as they are called, have been much larger than Earth, gas giants like Jupiter or Neptune. However, last week European scientists using the COROT telescope discovered a planet with a diameter less than twice that of Earth orbiting a Sun-like star. Before you pack your bags, please realize that this planet is so close to its star that it has an estimated surface temperature of greater than 2000 degrees Fahrenheit. It orbits a dim star in the constellation Monoceros the unicorn in the middle of the triangle formed by the stars Betelgeuse, Sirius, and Procyon. This star, too dim to be visible even with binoculars, is four fists above due south at 9 p.m. For more information, go to http://www.skyandtelescope.com/news/38820797.html
Friday: Mercury is less than a half a fist above the southeast horizon at 6:30 a.m. Over the next few weeks, Mercury will get higher and higher in the morning sky.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Sunday: Tonight and tomorrow morning’s full moon is in the constellation Leo the lion. Because February is typically the snowiest month, some Native American tribes in the northeastern United States called the full moon in February the Full Snow Moon. Some tribes referred to how the harsh winter conditions affected their food gathering ability by calling the February full moon the Full Hunger Moon. The name Full Hunger Moon is especially appropriate this month because Leo the lion seems to be stalking the moon throughout the night to hunt it down for food.
Monday: Regulus, the brightest star in the constellation Leo the lion is about a thumb width to the left of the Moon at 7 p.m. They are both low on the eastern horizon.
Tuesday: Hydra is not the only long, squiggly constellation in the sky. Draco the dragon wraps around the cup of the little dipper. The head of the dragon is one fist above due north at 7:30 p.m. Eltanin, the brightest star in the constellation, is at one corner of the trapezoid-shaped head of Draco. Eridanus the river starts next to Rigel, the bright star in the lower right corner of Orion, and meanders down below the south horizon. Rigel is three and a half fists above due south at 7:30 p.m. That means at 7:30 tonight, there are long, squiggly constellations in the lower northern, southern and eastern sky.
Wednesday: Saturn is less than a fist above the Moon at 6 a.m. They are about two fists above the west-southwest horizon.
Thursday: In the past decade or so, astronomers have discovered 339 planets orbiting stars other than our Sun. All of these exoplanets, as they are called, have been much larger than Earth, gas giants like Jupiter or Neptune. However, last week European scientists using the COROT telescope discovered a planet with a diameter less than twice that of Earth orbiting a Sun-like star. Before you pack your bags, please realize that this planet is so close to its star that it has an estimated surface temperature of greater than 2000 degrees Fahrenheit. It orbits a dim star in the constellation Monoceros the unicorn in the middle of the triangle formed by the stars Betelgeuse, Sirius, and Procyon. This star, too dim to be visible even with binoculars, is four fists above due south at 9 p.m. For more information, go to http://www.skyandtelescope.com/news/38820797.html
Friday: Mercury is less than a half a fist above the southeast horizon at 6:30 a.m. Over the next few weeks, Mercury will get higher and higher in the morning sky.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Thursday, January 29, 2009
The Ellensburg Sky for the week of 1/31/09
Saturday: February’s “Hot Topic” for the International Year of Astronomy is the Solar System. Galileo’s discoveries about the Sun, the Moon, Venus, and Jupiter helped move us from a privileged spot in the center of the perfect heavens to one of billions of planets in the turbulent neighborhood known as the Milky Way Galaxy. Some may say that makes them feel small and insignificant. I say it makes me feel empowered. All those planets and very few, perhaps only one, inhabited by beings with the capability to comprehend their surroundings. It is better to understand your situation as one in a billion than to blindly and incorrectly think you are at the top. Go to http://astronomy2009.nasa.gov/topics_feb.htm for more information about the Solar System. Go outside and look one and a half fists held upright and at arm’s length above the west-southwest horizon for more information about Venus.
Sunday: Today is Groundhog Day. If Punxsutawney Phil doesn’t see his shadow this morning, he is telling us that he follows the Chinese calendar and that spring starts early. On the Chinese calendar, equinoxes and solstices occur in the middle of their respective seasons. In order for the vernal equinox to occur in the middle of spring, spring must start on February 3 or 4, depending on the year. Thus, if Phil doesn’t see his shadow, spring may start on February 3 or 4 as on the Chinese calendar. If Phil sees his shadow, he is telling us he agrees with the western calendar and that there will be six more weeks of winter meaning spring will start near March 20.
Monday: Tonight’s first quarter Moon is in the constellation Aries the ram. Go to http://astronomy2009.nasa.gov/observe_feb.htm to learn more about the Moon.
Tuesday: If you have a small telescope, or even a good pair of binoculars with a tripod, you can improve on Galileo’s initial discovery of Saturn. And, if Paolo Galluzzi, director of the Museum of History and Science in Florence, is correct, Galileo’s poor eyesight may have influenced his initial judgment of the ringed planet. Galileo thought that Saturn had an inflated side and not spherical. British and Italian scientists want to exhume Galileo’s body to test his DNA to determine the extent of his vision problems. Find Saturn using your good eyes nearly two fists above the east-southeast at 10 p.m.
Wednesday: Altair, one third of the Summer Triangle, is about one and a half fists above due east at 6 a.m.
Thursday: The bright star Arcturus is one fist above the east-northeast horizon at 11 p.m.
Friday: Comet Lulin, discovered in July 2007, should be visible with binoculars for the next few weeks. At 6 a.m., it is near a bright star making it easier to find. First find the bright star Spica two and a half fists above the south-southwest horizon. About two fists to the left is a triangle that makes up the top of the constellation Libra the scales. Aim your binoculars at the triangle star, called Zuben Elgenubi, that is nearest to Spica. Comet Lulin should be right above Zuben Elgenubi.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Sunday: Today is Groundhog Day. If Punxsutawney Phil doesn’t see his shadow this morning, he is telling us that he follows the Chinese calendar and that spring starts early. On the Chinese calendar, equinoxes and solstices occur in the middle of their respective seasons. In order for the vernal equinox to occur in the middle of spring, spring must start on February 3 or 4, depending on the year. Thus, if Phil doesn’t see his shadow, spring may start on February 3 or 4 as on the Chinese calendar. If Phil sees his shadow, he is telling us he agrees with the western calendar and that there will be six more weeks of winter meaning spring will start near March 20.
Monday: Tonight’s first quarter Moon is in the constellation Aries the ram. Go to http://astronomy2009.nasa.gov/observe_feb.htm to learn more about the Moon.
Tuesday: If you have a small telescope, or even a good pair of binoculars with a tripod, you can improve on Galileo’s initial discovery of Saturn. And, if Paolo Galluzzi, director of the Museum of History and Science in Florence, is correct, Galileo’s poor eyesight may have influenced his initial judgment of the ringed planet. Galileo thought that Saturn had an inflated side and not spherical. British and Italian scientists want to exhume Galileo’s body to test his DNA to determine the extent of his vision problems. Find Saturn using your good eyes nearly two fists above the east-southeast at 10 p.m.
Wednesday: Altair, one third of the Summer Triangle, is about one and a half fists above due east at 6 a.m.
Thursday: The bright star Arcturus is one fist above the east-northeast horizon at 11 p.m.
Friday: Comet Lulin, discovered in July 2007, should be visible with binoculars for the next few weeks. At 6 a.m., it is near a bright star making it easier to find. First find the bright star Spica two and a half fists above the south-southwest horizon. About two fists to the left is a triangle that makes up the top of the constellation Libra the scales. Aim your binoculars at the triangle star, called Zuben Elgenubi, that is nearest to Spica. Comet Lulin should be right above Zuben Elgenubi.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Thursday, January 22, 2009
The Ellensburg sky for the week of 1/24/09
Saturday: Draco Malfoy makes an appearance in all seven books of the Harry Potter series. Perhaps you’ve heard of these. But, the constellation Draco the dragon makes an appearance in the sky every night. It is a circumpolar constellation as viewed from Ellensburg meaning it never goes below the horizon. The head of the dragon is one fist held upright and at arm’s length above due north at 9 p.m. Eltanin, the brightest star in the constellation, is at one corner of the trapezoid-shaped head of Draco.
Sunday: Saturn is about one fist above the east horizon at 10 p.m. For more information about Saturn, go to http://solarsystem.nasa.gov/planets/profile.cfm?Object=Saturn.
Monday: If you are planning a trip to the Indian Ocean or Indonesia today, you will see an annular solar eclipse. Despite the word similarity, annular does not mean once a year. Annular means “ring-shaped”. An annular solar eclipse occurs when the Moon, as seen from Earth, is relatively far from Earth in its orbit and not large enough to cover the Sun even though they are nearly perfectly lined up. Three days ago, the Moon was at apogee, or the farthest point from the Earth in its orbit. By today, its apparent size still is not big enough to cover the entire Sun. Instead, there is bright ring or annulus around the Moon. The resulting eclipse is called an annular solar eclipse because of this ring.
Here is the difference between a total solar eclipse and an annular solar eclipse. Take a coin out of your pocket. Close one eye. Hold the coin close to your open eye such that you completely cover a round object across the room. This represents a total eclipse of that object. Now, slowly move the coin away from your eye until you can see an outline of the round object. This is an annular eclipse of that object. Your coin, representing the Moon, has too small of an angular size to completely cover the round object across the room, representing the Sun.
Tuesday: The bright star Arcturus is about a half a fist above the east-northeast horizon at 11 p.m.
Wednesday: “The crow rises at midnight” said spy number one. “It arrived in the southeast sky” replied spy number two. “I’m sorry. I don’t recognize that code” added spy number three. Spy one exclaimed, “That’s because it’s not a code, you idiot. I’m talking about the constellation Corvus the crow.” This is very bad spy movie dialogue to remind you that Corvus had a very bad life. According to one myth, Corvus brought the god Apollo the news that his girlfriend was seeing someone else. In a classic case of punishing the messenger, Apollo turned the crow black. The box-shaped Corvus is rising above the southeast horizon at midnight tonight, just like the spies said.
Thursday: Venus is less than a half a fist to the upper left of the Moon this evening. They are about one foot above the west horizon at 8 p.m. For more information about Venus, go to http://solarsystem.nasa.gov/planets/profile.cfm?Object=Venus.
Friday: Spica, the brightest star in Virgo, is a half a fist above the east-southeast horizon at 6 a.m.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Sunday: Saturn is about one fist above the east horizon at 10 p.m. For more information about Saturn, go to http://solarsystem.nasa.gov/planets/profile.cfm?Object=Saturn.
Monday: If you are planning a trip to the Indian Ocean or Indonesia today, you will see an annular solar eclipse. Despite the word similarity, annular does not mean once a year. Annular means “ring-shaped”. An annular solar eclipse occurs when the Moon, as seen from Earth, is relatively far from Earth in its orbit and not large enough to cover the Sun even though they are nearly perfectly lined up. Three days ago, the Moon was at apogee, or the farthest point from the Earth in its orbit. By today, its apparent size still is not big enough to cover the entire Sun. Instead, there is bright ring or annulus around the Moon. The resulting eclipse is called an annular solar eclipse because of this ring.
Here is the difference between a total solar eclipse and an annular solar eclipse. Take a coin out of your pocket. Close one eye. Hold the coin close to your open eye such that you completely cover a round object across the room. This represents a total eclipse of that object. Now, slowly move the coin away from your eye until you can see an outline of the round object. This is an annular eclipse of that object. Your coin, representing the Moon, has too small of an angular size to completely cover the round object across the room, representing the Sun.
Tuesday: The bright star Arcturus is about a half a fist above the east-northeast horizon at 11 p.m.
Wednesday: “The crow rises at midnight” said spy number one. “It arrived in the southeast sky” replied spy number two. “I’m sorry. I don’t recognize that code” added spy number three. Spy one exclaimed, “That’s because it’s not a code, you idiot. I’m talking about the constellation Corvus the crow.” This is very bad spy movie dialogue to remind you that Corvus had a very bad life. According to one myth, Corvus brought the god Apollo the news that his girlfriend was seeing someone else. In a classic case of punishing the messenger, Apollo turned the crow black. The box-shaped Corvus is rising above the southeast horizon at midnight tonight, just like the spies said.
Thursday: Venus is less than a half a fist to the upper left of the Moon this evening. They are about one foot above the west horizon at 8 p.m. For more information about Venus, go to http://solarsystem.nasa.gov/planets/profile.cfm?Object=Venus.
Friday: Spica, the brightest star in Virgo, is a half a fist above the east-southeast horizon at 6 a.m.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Thursday, January 15, 2009
The Ellensburg sky for the week of 1/17/09
Saturday: Astronomers have just solved a mystery about the fifth brightest star in the nighttime sky, Vega. For decades, astronomers have known that Vega is about 50% brighter than it should be, given its temperature. That gave scientists two choices: either revise their temperature-brightness model or look for a characteristic they have overlooked when applying the model. Some people say if an observation goes against a scientific model, the model is bad and should be thrown out. But, that is not how science works. Models in science are built using many observations. It does not make sense to abandon a model when one observation seems to refute it. So, scientists looked for a reason Vega is brighter than expected. They finally found one. Using a powerful array of telescopes, astronomers noted that Vega is oblong, due to rapid rotation, and we are observing the star nearly pole-on. Thus, we are observing the widest possible diameter for Vega. The light from this oblong star is spread out more than the light from a round star. Spread out light means the star appears brighter. Look for brighter than expected Vega one fist held upright and at arm’s length above the northeast horizon at 7 p.m.
Sunday: This morning’s last quarter moon is in the constellation Virgo. Virgo, the second largest constellation in the sky, after Hydra, is typically identified with Dike, the goddess of justice. A stature of justice at a courthouse is really a statue of Virgo.
Monday: Sirius, the brightest star in the nighttime sky, is two and a half fists help upright and at arm’s length above the south horizon at 10 p.m. Some stars, such as Antares and Betelgeuse, appear to us to be bright because they are luminous supergiant stars. Sirius appears bright to us because it is just down the block in our galactic neighborhood. In fact, if you shrunk the Milky Way galaxy down to the size of Ellensburg, Sirius would be about one foot away from your nose.
Tuesday: Venus is nearly three fists above the southwest horizon at 6 p.m.
Wednesday: The brightest star in Scorpius is Antares which means “rival of Mars”. But, this morning, Antares is a rival of the moon. So the moon, like most things when faced with a rival, will attempt to overpower Antares by blocking, or occulting, it. From Ellensburg, the moon will appear to pass less than a finger’s width below Antares. At 6:30 a.m., they will be one fist above the south-southeast horizon. The complete occultation will be visible from central South America.
Thursday: Saturn is one fist above the east horizon at 10 p.m.
Friday: Did you see Saturn last night? You may have confused it with Regulus, the brightest star in the constellation Leo the lion. Regulus is three fists above the east-southeast horizon at 10 p.m., about two fists to the upper right of Saturn.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Sunday: This morning’s last quarter moon is in the constellation Virgo. Virgo, the second largest constellation in the sky, after Hydra, is typically identified with Dike, the goddess of justice. A stature of justice at a courthouse is really a statue of Virgo.
Monday: Sirius, the brightest star in the nighttime sky, is two and a half fists help upright and at arm’s length above the south horizon at 10 p.m. Some stars, such as Antares and Betelgeuse, appear to us to be bright because they are luminous supergiant stars. Sirius appears bright to us because it is just down the block in our galactic neighborhood. In fact, if you shrunk the Milky Way galaxy down to the size of Ellensburg, Sirius would be about one foot away from your nose.
Tuesday: Venus is nearly three fists above the southwest horizon at 6 p.m.
Wednesday: The brightest star in Scorpius is Antares which means “rival of Mars”. But, this morning, Antares is a rival of the moon. So the moon, like most things when faced with a rival, will attempt to overpower Antares by blocking, or occulting, it. From Ellensburg, the moon will appear to pass less than a finger’s width below Antares. At 6:30 a.m., they will be one fist above the south-southeast horizon. The complete occultation will be visible from central South America.
Thursday: Saturn is one fist above the east horizon at 10 p.m.
Friday: Did you see Saturn last night? You may have confused it with Regulus, the brightest star in the constellation Leo the lion. Regulus is three fists above the east-southeast horizon at 10 p.m., about two fists to the upper right of Saturn.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
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