The Ellensburg, WA sky for the week of September 2, 2023

Saturday: Jupiter and Saturn are both in the sky at 11:00 p.m. Saturn is about two and a half fists held upright and at arm’s length above the south-southeastern horizon and Jupiter is one fist above the east-northeastern horizon. 

Sunday: “Excuse me, do you have the time?”

“No, but the Big Dipper does.”

You can use the orientation of the Big Dipper to tell time with a precision of about 15-30 minutes. First, find the two stars at the far end of the Big Dipper cup, the stars that do not touch the handle. Draw an imaginary line segment starting at the North Star and passing through the two Big Dipper cup stars. Now, draw a big circle around the North Star. Your circle is a 24-hour clock. Number the circle from 0 hours at the top, counterclockwise to 12 hours at the bottom of the circle, and back up to 24 hours at the top. (O hours and 24 hours are the same on this clock because the day is 24 hours long.) The hour number on the big circle closest to where your imaginary line intersects this circle is called your raw time. Due to the location of the Big Dipper compared to the rest of the stars, the time nearest the intersection (the raw time) is correct for March 6. For any other night, subtract two times the number of months the current date is after March 6 from the raw time. For example, let’s say the imaginary line between the North Star and the Dipper stars is pointed to the right. That means the raw time is 18 hours or 6 p.m. If you made this observation tonight, which is six months after March 6, you would subtract two times six or 12 hours from the raw time.  Don’t forget to convert for daylight savings time if needed. If you prefer a more visual tool, and a fun project to do with your kids, there is a simple “star clock” template and instructions at https://skyandtelescope.org/observing/make-a-star-clock/. Use this paper star clock whenever your watch is broken. The Big Dipper is in the northwestern sky at 9:00 p.m. tonight.

Monday: Labor Day was the brainchild of labor unions and is dedicated to American workers. The first Labor Day was celebrated in 1882. The Greek mythical hero Hercules probably wished there was a Labor Day to commemorate his work. As punishment for killing his family while he was temporarily insane, he had to perform twelve nearly impossible tasks such as killing monsters or stealing things from deities. Hmmm. Maybe we shouldn’t commemorate his labors. But we can enjoy his constellation. The keystone asterism representing the body of Hercules is six fists held upright and at arm’s length above the western horizon at 10:00 p.m. For more information about the Labors of Hercules, go to http://goo.gl/ozVF5.

Tuesday: Had the script been written a little differently for a well-known Robin Williams movie, we might have heard Mr. Williams shout, “Goooood Morning Orion the hunter”. Orion is typically thought of as a winter constellation. But, it makes its first appearance in the early morning summer sky. The lowest corner of Orion’s body, represented by the star Saiph (pronounced “safe”), rises at 2:30 a.m. By 5:30 a.m., Orion’s belt is three fists above the southeastern horizon.

Wednesday: School starts this week so it is time for a little geometry review. A square is a regular quadrilateral. This means it has four equal sides, four equal angles, and wears old fashioned clothing. Go outside at 10:00 p.m. tonight with a notebook in hand to sketch one. The Great Square of Pegasus is balancing on its corner two and a half fists above the eastern horizon. The top corner of the square is two fists above the bottom corner. The other two corners are to the left and right of the line segment connecting the top and bottom corners.

Thursday: Geometry review, part 2. Go outside at 10:00 p.m. tonight with a notebook in hand. (Good teaching involves a little repetition.) 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. Altair is five fists above the southern horizon. Vega, the brightest star in the triangle, is seven and a half fists above the southwestern horizon. Deneb is a little bit east of straight overhead.

Friday: Venus is one and a half fists above due east at 5:30 a.m.

The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

The Ellensburg, WA sky for the week of August 26, 2023

Saturday: Saturn is in opposition tonight. That doesn’t mean that Saturn is stubborn. Opposition means that Saturn is on the opposite side of the Earth as the Sun. When an object is in opposition, it is at its highest point in the sky during the darkest time of the day. Thus, opposition is typically the best time to observe a planet. Saturn is about three fists above due south at 1:00 a.m. It is nearly two fists above due southeast at 10:00 p.m. Careful readers of this column may recall that Saturn is in opposition on nearly the same date every year: June 26, 2018, July 9, 2019, July 21, 2020, August 1, 2021, and August 14, 2022. An outer planet is in opposition when Earth passes it up as both orbit the Sun. The farther out a planet is, the less it has moved along its orbit, and the closer it is to exactly one year from one Earth passing to the next. For comparison, it is about 18 months between successive oppositions for Mars.

Sunday: Mars is just above the western horizon at 8:30 p.m. Over the next few weeks, Mars will move behind the Sun and into the morning sky. You don’t have to wait that long to see Jupiter.  It is about a fist and a half above the eastern horizon by midnight tonight.

Monday: You’ve seen all of the top 100 lists: top 100 ways to bench press, top 100 Uzbek astronomers, etc. Now get excited for this week’s full Moon by reading about and finding some of the lunar 100. Go to http://goo.gl/ldGvH6. This list describes 100 interesting landmarks on the Moon that are visible from Earth. They are listed from easiest to see, starting with the entire moon itself at number 1, to most difficult (Mare Marginis swirls, anyone?). Stay up all night to binge watch the moon or just make a few observations a month. It’s your decision. It’s our moon. Start your viewing tonight at 9:00 p.m. when the Moon is one fist above due southwest. I suggest starting with Mare Crisium, the circular, dark, basaltic plain in the upper right-hand portion of the moon. Items such as Crisium were named "Mare" by early astronomers who mistook them for seas, instead of the hardened lava beds that they really are. 

Tuesday: Need a caffeine pick-me-up? Make it a double. Need an astronomy pick-me-up? Make it a double double. Find Vega, in the constellation Lyra the lyre, nearly straight overhead at 9:00 tonight. Less than half a fist to the east (or left if you are facing south) of the bright bluish star Vega is the “star” Epsilon Lyra. If you look at Epsilon Lyra through binoculars, it looks like two stars. If you look at Epsilon Lyra through a large enough telescope, you will notice that each star in the pair is itself a pair of stars. Each star in the double is double. Hence, Epsilon Lyra is known as the double double. The stars in each pair orbit a point approximately in the center of each respective pair. The pairs themselves orbit a point between the two pairs.

Wednesday: “I’m a little teapot, short and stout. The galactic center, I pour it out.” (I’m a Little Teapot, astronomy version, 2023.) 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 of 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’t see the actual galactic center, you can gaze in the direction of the center by looking just to the right of the teapot asterism in the constellation Sagittarius. This point is about one fist above the south-southwestern horizon at 9:00 p.m.

Thursday: Venus is nearly one fist above the eastern horizon at 5:30 a.m.

Friday: School starts soon. One of the most important lessons to learn in science class is to always save your data. Even if the data looks “wrong” or you don’t think it contains important information, you never know what future researchers might find in it. Two years ago, Kepler space telescope scientists reanalyzed older data and discovered an Earth-sized planet orbiting in the habitable zone of its host star. It turns out the previous computer algorithm misidentified it. Maybe there are other Earth-cousins hiding in the data somewhere. Read more about it at https://www.nasa.gov/press-release/earth-size-habitable-zone-planet-found-hidden-in-early-nasa-kepler-data.

The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

The Ellensburg, WA sky for the week of August 19, 2023

Saturday: “The sky is black (or light polluted), the stars are white (or red or orange or yellow or blue), the whole world gazes upon the sight (except where there are too many city lights or people are lazy.” Wow. It is difficult to write a flowing set of lyrics when there are so many parenthetical thoughts. Most people think of the sky’s blackness as a lack of stars. But dark patches in the Milky Way are actually massive clouds of dust that are blocking the stars behind them. Two of the most prominent are dark nebulae B142 and B143 in the constellation Aquila the eagle. These are easy to find and enjoy with binoculars. First find the bright white star Altair, five fists held upright and at arm’s length above due south at 11:00 p.m. Then move your binoculars up a little bit to the next bright star Tarazed, about one fifth as bright. B142 and B143 are to the upper right of Tarazed. They make an “E” shape in the sky; fitting because American astronomer E. E. Barnard first proposed that these were dust clouds and not simply big spaces between the stars. For more information about dark nebulae, including many more to look at with binoculars, go to https://goo.gl/9tiqdh.  

Sunday: Arcturus is two and a half fists above due west at 10:00 p.m. This star, whose name means bear watcher, is the brightest in the sky’s northern hemisphere. It follows Ursa Major, the Great Bear, around the North Star. Arcturus is the closest giant star to Earth. It is one of the few stars whose diameter can be measured directly rather than being inferred from its density and mass, which themselves are derived from other parameters. 

Monday: Mars is a half a fist above the western horizon at 8:30 p.m.

Tuesday: Deneb is straight overhead at 11:30 p.m. When you look at Deneb, you are seeing light that left Deneb about 2,600 years ago.

Wednesday: All stars rotate. Our Sun takes a little less than one Earth month to rotate once on its axis. Astronomers studied the relationship between mass, stellar rotation, and planetary formation by aiming NASA’s recently retired Kepler space telescope toward the Pleiades open star cluster. All 1,000 stars in this group are nearly the same age, 125 million years old. Since all of the stars are the same age and formed from the same set of materials, astronomers have the ideal “laboratory” to isolate the role star mass plays on star rotation and evolution. Read more about the findings at http://goo.gl/osijIY. See the Pleiades for yourself, nearly one fist above the east-northeastern horizon at 11:30 p.m.

Thursday: At 11:00 p.m., Saturn is two and a half fists above the southeastern horizon and Jupiter is one fist above the eastern horizon.

Friday: Seventeenth century astronomers documented the appearance of a new star, or “nova”, in 1670. However, as modern astronomers studied the records of the star, called Nova Vulpeculae 1670, they realized it didn’t have the characteristics of a typical nova because it didn’t repeatedly brighten and dim. It brightened twice and disappeared for good. Turning their telescopes to the region, they discovered the chemical signature to be characteristic of a very rare collision of two stars. For more information about this discovery, go to http://goo.gl/rJnC2G. Nova Vulpeculae 1670 is right below the binary star system Alberio, the head of Cygnus the swan. Alberio is five fists above due south at 10:30 p.m.

The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

The Ellensburg, WA sky for the week of August 12, 2023

Saturday: The Perseid meteor shower peaks tonight. The moon will be in the new phase early in the week meaning even the dimmer meteors will be visible. In case you decide to stay in bed this week, the shower is active until about September 1 so you may still enjoy an increased number of meteors later. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about three fists held upright and at arm’s length above the northeastern horizon at 11:00 p.m. By dawn, this point is nearly straight overhead. For tips about optimizing your viewing this year, go to https://earthsky.org/?p=165416  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.

Sunday: One minor Harry Potter character actually has two well-known star names: Regulus Arcturus Black, the brother of Sirius Black who is Harry Potter’s godfather. Regulus Black was a former follower of Voldemort, the bad guy of the Harry Potter series. However, Regulus tried to dissociate himself from Voldemort and was killed. In the sixth book, Harry found an important note written by someone known only by the initials R.A.B. Hmmm. R.A.B. Regulus Arcturus Black perhaps? Regulus the star is right in line with the Sun at this time of year so it is not visible. Arcturus, the second brightest star visible in the nighttime sky in Washington and at Hogwarts, is three fists above the western horizon at 10:00 p.m.

Monday: Bellatrix Lestrange is Sirius Black’s cousin. But, certainly not kissing cousins. They are killing cousins. Bellatrix kills Sirius in a fight at the Ministry of Magic. Bellatrix the star is the third brightest star in the constellation Orion the hunter. It is three fists above the east-southeastern horizon at 5:00 a.m. Jupiter is five fists above the southeastern horizon.

Tuesday: Of course, Bellatrix is in cahoots with “he who must not be named”. Now, that’s a poorly written sentence, using an obscure synonym for “conspiring” and a vague reference to someone. I must be under the curse “writicus dreadfulium”. Clearly this is the work of Tom Riddle, whose mother is named Merope Gaunt. Merope is a star in the Pleiades, an open star cluster about five and a half fists above the east-southeastern horizon at 5:00 a.m. Saturn is nearly two fists above the southwestern horizon.

Wednesday: Draco Malfoy, Harry Potter’s young nemesis, is related to Sirius Black. Draco’s mother, Narcissa Black (Sirius’ cousin), helped develop a plan to trap Harry at the Ministry of Magic in the fifth book. Draco’s namesake, the constellation Draco the dragon, is one of the largest constellations in the sky, winding around the North Star. Draco’s head is a four-sided figure nearly straight overhead at 9:00 p.m. In case you didn’t get up at 5:00 a.m. yesterday to look for Saturn, you can find it just above the east-southeastern horizon at 9:00 p.m.

Thursday: Antares, the brightest star in the constellation Scorpius, is one and a half fists above the south-southwestern horizon at 9:30 p.m. Draco Malfoy was so impressed with this constellation name that he used it for the first name of his son.

Friday: Not every woman in the Black family is evil. Let’s focus on the good. Andromeda Black, Bellatrix’s sister, is a good witch and the mother of Tonks, a young witch from the last few Harry Potter books. (If these Harry Potter references are confusing, you better start reading the books.) Andromeda the constellation is an interesting one. It contains the Andromeda galaxy, the most distant object visible with the naked eye from a dark site. To locate the Andromeda Galaxy, first find the Great Square of Pegasus. At 11:30 p.m., the left hand corner of the square is four fists above the eastern horizon. Less than two fists to the left and down a little bit is another star the same brightness as the star at the corner of the square. From that star, hop about a half a fist up to a star that is about one fourth as bright. Less than another half fist in the same direction is a fuzzy oval patch of light known as the Andromeda Galaxy. The galaxy is impressive to see in binoculars. It consists of about one trillion stars and is 2.5 million light years away. If you are having trouble seeing the Andromeda Galaxy, shoot for an easier target.

The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

The Ellensburg, WA sky for the week of August 5, 2023

Saturday: Saturn is one and a half fists held upright and at arms length above the southeastern horizon at 11:00 p.m.

Sunday: It is not winter yet. But Orion, thought of as a winter constellation, is just above the east-southeastern horizon at 5:00 a.m. By the actual winter, it will be visible in the evening sky. 

Monday: The moon and Jupiter rise at about 11:30 p.m. By midnight, they are just above the east-northeastern horizon. Jupiter is about a finger-width below the moon.

Tuesday: The Gemini Twins are rising right before the Sun. At 5:00 a.m., Pollux is one and a half fists above the east-northeastern horizon. Slightly dimmer Castor is a half a fist above it. Pollux is the brightest star, as observed from Earth, known to have a planet orbiting it. The planet, creatively called Pollux b, has about twice the mass of Jupiter.

Wednesday: 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 the evening sky, it is east of the Sun so this occurrence is called the greatest eastern elongation. This evening will be the best evening to observe Mercury for the past few weeks. However, it is still very low in the sky, just above the western horizon at 9:00 p.m. Mars is to the upper left of Mercury.

Over the next few weeks, Mercury will move toward the Sun in the sky. By mid-September, it will be barely visible in the morning sky.

Thursday: If you want to show your loved ones a celestial sign that they should hang up their clothes, show them Brocchi's Cluster, commonly known as the Coat Hanger cluster because of its resemblance to an upside down coat hanger. The cluster is six fists above due south at 11:00 p.m., midway between Altair and Vega, the two brightest stars in the Summer Triangle. You'll need binoculars to make out the shape. First find Altair five fists above the southern horizon. Slowly move your binoculars up toward Vega. You will run into the coat hanger along the way. And while you are at it, put away your shoes.

Friday: The Perseid meteor shower peaks over the weekend with the peak of the peak coming Saturday night/Sunday morning. The moon will be in the new phase early next  week meaning even the dimmer meteors will be visible. In case you decide to stay in bed this week, the shower is active until about September 1 so you may still enjoy an increased number of meteors later. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about three fists above the northeast horizon at 11:00 p.m. By dawn, this point is nearly straight overhead. For tips about optimizing your viewing this year, go to https://earthsky.org/?p=165416  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.

The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.