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.
Thursday, January 29, 2009
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.
Thursday, January 8, 2009
The Ellensburg Sky for the week of 1/10/09
Saturday: Tonight is the largest full moon of the year. No, the Moon is not actually growing. Although at about 4.5 billion years of age, it could be forgiven a little middle age spread. The Moon’s orbit is elliptical. It gets closer to and farther from the Earth in a predictable pattern throughout the month. When the Moon is closest to the Earth (called perigee) during the full Moon phase, the Moon looks larger and brighter than usual. Tonight, the Moon will look about 14% wider and 30% brighter than the smallest full Moon.
Sunday: Who can forget that memorable song by Three Dog Constellations Night, “The sky is black. The stars are white. Together we learn to find the light.” Well, maybe it didn’t go like that. This is good because not all stars are white. Most stars are too dim to notice a color. But, the stars in the constellation Orion provide a noticeable contrast. Betelgeuse, five fists held upright and at arm’s length above due south at 10:30 p.m. is a red giant. Rigel, the bright star about two fists to the lower right of Betelgeuse, is a blue giant.
By the way, the three dog constellations are Canis Major, the greater dog; Canis Minor, the lesser dog; and Canes Venatici, the hunting dogs. Canis Major contains Sirius, the brightest star in the nighttime sky.
Monday: Mercury is less than half a fist above the west-southwest horizon at 5:30 p.m.
Tuesday: Saturn is about one fist above due east at 10:30 p.m.
Wednesday: This evening, Venus will be as far away from the Sun in the sky as it will get this orbital cycle. Last week, I wrote about the name of this "farthest away" point. Do you remember? Of course you do. It is known as the planet's greatest elongation. Venus is about two and a half fists above the southwest horizon at 5:15 p.m. Over the next two months, Venus will toward the Sun in the evening sky. By late March, it will be lost in the glare of the setting Sun.
Thursday: How do you study the life cycle of a dog? Easy. Get a dog from the animal shelter, care for it for 15 years and study it. How do you study the life cycle of a star? Easy. Pick a star, watch it for a few billion years, and…. Wait a minute. Astronomers can’t observe something for a few billion years. Instead, they study stars that are at different points in their long life cycle and piece together the information from those different stars. What they do is like studying a one-year-old dog for a few minutes, then studying a different two-year-old dog for a few minutes, and so on. The sky in and near the constellation Orion provides an example of four objects at different points of star life.
First, find Rigel, the bright star in the lower right corner of the constellation Orion. It is three and a half fists above due south at 9:30 p.m. About one fist up and to the left are the three objects of Orion’s sword holder. The middle “star” is really a star forming region called the Orion nebula. There you’ll find baby Suns. Now, look about two fists to the right and a little below Rigel. You should be looking at a star that is about one tenth as bright as Rigel but still the brightest in its local region. The third star to the right of that star is Epsilon Eridani, the most Sun-like close and bright star. Betelgeuse, in the upper left corner of Orion, is a star at the end of its life that started out life a bit larger than the Sun.
Friday: Spica, the brightest star in Virgo, is three fists above the south 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: Who can forget that memorable song by Three Dog Constellations Night, “The sky is black. The stars are white. Together we learn to find the light.” Well, maybe it didn’t go like that. This is good because not all stars are white. Most stars are too dim to notice a color. But, the stars in the constellation Orion provide a noticeable contrast. Betelgeuse, five fists held upright and at arm’s length above due south at 10:30 p.m. is a red giant. Rigel, the bright star about two fists to the lower right of Betelgeuse, is a blue giant.
By the way, the three dog constellations are Canis Major, the greater dog; Canis Minor, the lesser dog; and Canes Venatici, the hunting dogs. Canis Major contains Sirius, the brightest star in the nighttime sky.
Monday: Mercury is less than half a fist above the west-southwest horizon at 5:30 p.m.
Tuesday: Saturn is about one fist above due east at 10:30 p.m.
Wednesday: This evening, Venus will be as far away from the Sun in the sky as it will get this orbital cycle. Last week, I wrote about the name of this "farthest away" point. Do you remember? Of course you do. It is known as the planet's greatest elongation. Venus is about two and a half fists above the southwest horizon at 5:15 p.m. Over the next two months, Venus will toward the Sun in the evening sky. By late March, it will be lost in the glare of the setting Sun.
Thursday: How do you study the life cycle of a dog? Easy. Get a dog from the animal shelter, care for it for 15 years and study it. How do you study the life cycle of a star? Easy. Pick a star, watch it for a few billion years, and…. Wait a minute. Astronomers can’t observe something for a few billion years. Instead, they study stars that are at different points in their long life cycle and piece together the information from those different stars. What they do is like studying a one-year-old dog for a few minutes, then studying a different two-year-old dog for a few minutes, and so on. The sky in and near the constellation Orion provides an example of four objects at different points of star life.
First, find Rigel, the bright star in the lower right corner of the constellation Orion. It is three and a half fists above due south at 9:30 p.m. About one fist up and to the left are the three objects of Orion’s sword holder. The middle “star” is really a star forming region called the Orion nebula. There you’ll find baby Suns. Now, look about two fists to the right and a little below Rigel. You should be looking at a star that is about one tenth as bright as Rigel but still the brightest in its local region. The third star to the right of that star is Epsilon Eridani, the most Sun-like close and bright star. Betelgeuse, in the upper left corner of Orion, is a star at the end of its life that started out life a bit larger than the Sun.
Friday: Spica, the brightest star in Virgo, is three fists above the south 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 1, 2009
The Ellensburg Sky for the week of 1/3/09
Saturday: Tomorrow morning, Mercury will be as far away from the Sun in the sky as it will get this orbital cycle. This "farthest away" point is known as the planet's greatest elongation. Since Mercury is in evening sky, it is east of the Sun. Thus, this evening’s elongation is known as the greatest eastern elongation. (If you care to remember this in general, remember both eastern and evening start with the letter "e".) Tonight and tomorrow will be the best nights to observe Mercury for the next few months. Mercury is about a half a fist held upright and at arm’s length above the southwest horizon at 5:15 p.m. Over the next two weeks, Mercury will toward the Sun in the sky. By late January, it will be visible in the morning sky.
Sunday: If the Sun looks big today, your eyes are not playing tricks on you. The Earth is at perihelion at about 7 a.m. If you dig out your Greek language textbook, you’ll see that peri- means “in close proximity” and helios means “Sun”. So, perihelion is when an object is closest to the Sun in its orbit. Since it is winter in the Northern Hemisphere now, the seasonal temperature changes must not be caused by the Earth getting farther from and closer to the Sun. Otherwise, we’d have summer when the Earth is closest to the Sun. The seasons are caused by the angle of the sunlight hitting the Earth. In the winter, sunlight hits the Earth at a very low angle, an angle far from perpendicular or straight up and down. This means that a given “bundle” of sunlight is spread out over a large area and does not warm the surface as much as the same bundle in the summer.
Monday: Has it been tougher to wake up this past week? It should have been because the sunrise has been getting later as recently as this past weekend. December 22 was the shortest day of the year. But, because the Earth’s orbit around the Sun is elliptical and not circular, the Earth does not travel at a constant speed. It moves faster when it is closer to the Sun and slower when it is farther away. This leads to the latest sunrise occurring in early January and the earliest sunset occurring in early December, not on the first day of winter, the shortest day of the year. On the first day of winter, the interval between sunrise and sunset is the shortest.
Tuesday: This month’s “Hot Topic” for the International Year of Astronomy is Telescopes and Space Probes. Observational astronomy has made significant advances since 1609 when Galileo turned his simple telescope to the sky to discover Jupiter’s four largest moons, the phases of Venus, and the individual stars of the Milky Way. In 2009, astronomers rely on space probes and telescopes to make discoveries that approach the significance of Galileo’s discoveries. Go to http://astronomy2009.nasa.gov/topics_jan.htm for more information about these modern day Starry Messengers.
Wednesday: Venus is two fists above the southwest horizon at 6 p.m. Go to http://astronomy2009.nasa.gov/observe_jan.htm to learn more about Venus.
Thursday: Sirius, the brightest star in the nighttime sky, rises at about 6:40 p.m. By 8:30 p.m., it is about a fist and a half above due southeast.
Friday: Jupiter is just barely hanging out in the evening sky. It is less than a half a fist above the southwest horizon at 5 p.m. Say “good bye” to Jupiter for a few weeks as it gets lost in the glare of the Sun.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
Sunday: If the Sun looks big today, your eyes are not playing tricks on you. The Earth is at perihelion at about 7 a.m. If you dig out your Greek language textbook, you’ll see that peri- means “in close proximity” and helios means “Sun”. So, perihelion is when an object is closest to the Sun in its orbit. Since it is winter in the Northern Hemisphere now, the seasonal temperature changes must not be caused by the Earth getting farther from and closer to the Sun. Otherwise, we’d have summer when the Earth is closest to the Sun. The seasons are caused by the angle of the sunlight hitting the Earth. In the winter, sunlight hits the Earth at a very low angle, an angle far from perpendicular or straight up and down. This means that a given “bundle” of sunlight is spread out over a large area and does not warm the surface as much as the same bundle in the summer.
Monday: Has it been tougher to wake up this past week? It should have been because the sunrise has been getting later as recently as this past weekend. December 22 was the shortest day of the year. But, because the Earth’s orbit around the Sun is elliptical and not circular, the Earth does not travel at a constant speed. It moves faster when it is closer to the Sun and slower when it is farther away. This leads to the latest sunrise occurring in early January and the earliest sunset occurring in early December, not on the first day of winter, the shortest day of the year. On the first day of winter, the interval between sunrise and sunset is the shortest.
Tuesday: This month’s “Hot Topic” for the International Year of Astronomy is Telescopes and Space Probes. Observational astronomy has made significant advances since 1609 when Galileo turned his simple telescope to the sky to discover Jupiter’s four largest moons, the phases of Venus, and the individual stars of the Milky Way. In 2009, astronomers rely on space probes and telescopes to make discoveries that approach the significance of Galileo’s discoveries. Go to http://astronomy2009.nasa.gov/topics_jan.htm for more information about these modern day Starry Messengers.
Wednesday: Venus is two fists above the southwest horizon at 6 p.m. Go to http://astronomy2009.nasa.gov/observe_jan.htm to learn more about Venus.
Thursday: Sirius, the brightest star in the nighttime sky, rises at about 6:40 p.m. By 8:30 p.m., it is about a fist and a half above due southeast.
Friday: Jupiter is just barely hanging out in the evening sky. It is less than a half a fist above the southwest horizon at 5 p.m. Say “good bye” to Jupiter for a few weeks as it gets lost in the glare of the Sun.
The positional information in this column about stars and any planet except Mercury is accurate for the entire week.
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