The Ellensburg, WA sky for the week of September 28, 2024

Saturday: You learned about Cassiopeia last week. The astronomer Caroline Herschel discovered an open star cluster that looks like a rose over 200 years ago. This cluster, called Caroline’s Rose, is about 6,500 light years away and consists of about 1,000 stars that are one third the age of the Sun. Through binoculars, it looks like a fuzzy patch. At 10:00 p.m., find the star at the top of the sideways “W” known as Cassiopeia. It is six fists held upright and at arm’s length above due northeast. When that star is in the lower left portion of your field of view, Caroline’s Rose is in the center to upper right. For more information about Caroline’s Rose, go to https://stardate.org/radio/program/2020-09-09.

Sunday: Saturn is two and a half fists above the southeastern horizon at 9:00 p.m.

Monday: Since Halloween is a month away, the stores are filled with bags of candy clusters. Use this reminder to take time to look at a star cluster. The Hyades cluster is an open star cluster that represents the V-shaped face of Taurus the bull. It is one of the biggest and nearest star clusters with about 200 stars 150 light years away. The Hyades cluster was the first cluster to be the subject of detailed motion studies. These studies allowed astronomers to pinpoint the distance to the Hyades and provide important information about the scale of the universe. Aldebaran, about one fist above the east-northeastern horizon at 11:00 p.m., is a foreground star and not a part of the Hyades cluster.

Tuesday: Jupiter is one fist above the east-northeastern horizon at 11:00 p.m. By 1:00 a.m., Jupiter is three fists above due east and Mars is where Jupiter used to be, one fist above the east-northeastern horizon.

Wednesday: Need a caffeine pick-me-up? Make it a double. Need an astronomy pick-me-up? Make it a double double. Find the bright bluish star Vega, in the constellation Lyra the lyre, nearly six fists above due west at 10:00 p.m. Less than half a fist above 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.

Thursday: Four years ago, astronomers announced that they detected phosphine, a possible biosignature of life, in the upper atmosphere of Venus. Although the surface of Venus is inhospitable, astronomers have long speculated that the upper atmosphere could harbor life. Not Cloud City life from The Empire Strikes Back but maybe microbial life. Last year, astronomers concluded that the original scientists found the signature of sulfur dioxide, not life. Last year, the private company Rocket Lab published details about the first privately funded mission to another planet - their trip to Venus. The trip was originally scheduled to launch this year but has been delayed to at least 2025. This Venus storyline is an excellent example of science at work. In less than two years, science went from “we may have found a marker for life on Venus” to “it is unclear if we found a marker for life” to “we probably didn’t find a marker for life” to “let’s visit Venus to closely study the thing we thought was a marker for life”. Do an internet search of the words Venus and phosphine and read the articles to follow the story. To get yourself in the mood, go outside at 7:15 p.m. Venus is a half fist above the west-southwestern horizon at this time. Read more about the potential mission at https://www.space.com/rocket-lab-private-venus-mission-delayed-2025.

Friday: In 1987, the rock group Def Leppard sang “Pour some sugar on me, in the name of love. Pour some sugar on me, come on, fire me up.” In 2012, some European astronomers “found some sugar near stars, they were very young. Found some sugar near stars, out where planets formed.” Astronomers observed molecules of glycolaldehyde, a simple form of sugar, in the disk of gas and dust orbiting young binary stars. This is the first time astronomers have found this simple sugar so close to a star indicating that organic molecules can be found in planet-forming regions of stars. For more information, go to http://goo.gl/tfwy1.

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. All times are Pacific Time unless noted.

The Ellensburg, WA sky for the week of September 21, 2024

Saturday: At 5:30 a.m. PDT, the center of the Sun crosses the celestial equator and passes into the southern sky. The celestial equator is an imaginary line that divides the sky into a northern and southern half. When the Sun is in the southern half of the sky, it takes a shorter path from rising to setting. It also does not get as high in the sky at noon. This leads to shorter days and longer nights. Since the Sun crosses the celestial equator today, there is an instant when it is equally in the northern and southern sky, called the north and south celestial hemispheres. This so-called “equal night” is given by the Latin word equinox. Thus, today is known as the Autumnal Equinox. However, the day and night are not of equal duration today. The sun rises at 6:48 a.m. and sets at 7:00 p.m. in the northern latitudes of the United States. At these latitudes, day and night are closest to equal duration on Tuesday.

Sunday: “There’s water in them thar craters,” frozen water, that is. There has been speculation since the 1960s and indirect evidence since the 2000s of water on the Moon. Three years ago, astronomers studied data from four earlier missions. They noticed that the light reflecting off the bottom of craters near the lunar South Pole showed characteristics of light reflecting off pure ice. The water likely came from comet impacts or other solar system objects with trace amounts of water ice. Last summer, the Indian Space Research Organization became the fourth country to successfully land on the moon when Chandrayaan-3 landed near the lunar South Pole to study the water there. Read more about it at https://www.space.com/chandrayaan-3-moon-south-pole-why-nasa-wants-to-go-too. The moon is one fist above the north-northeast horizon at 11:00 p.m.

Monday: To the people of Ancient Greece, the stars that are about five and a half fists above the northeastern and eastern horizons, respectively, at 10:00 p.m. were known as Cassiopeia and Andromeda, a mythological queen, and her daughter. But not all cultures imagined the same pictures in the sky. To the people of Polynesia, the stars of Cassiopeia and Andromeda represented a dolphin, called Kwu. Cassiopeia formed its tail, the brightest stars of Andromeda formed its fins, and its fainter stars outlined the dolphin’s body.

Tuesday: Ask someone which day in September has the same duration day and night. Go ahead, ask someone. Why are you still reading this? I can wait. If that person says the first day of autumn, they are wrong. Today, three days after the first day of autumn, is the date in which day and night are closest in duration. There are two main reasons for this. First, the atmosphere acts like a lens, bending light from the Sun above the horizon when the Sun is actually below the horizon. This makes the Sun appear to rise before it actually rises and appear to set after it actually sets. Second, fall starts when the center of the Sun passes through the point called the autumnal equinox. But the Sun is not a point. The upper edge of the Sun rises about a minute before the center of the Sun and the lower edge sets a minute after the center of the Sun. Thus, even if we didn’t have an atmosphere that bends the sunlight, daytime on the first day of autumn would still be longer than 12 hours.

Wednesday: Mars is less than a half a fist to the lower right of the last quarter moon at 6:00 a.m. Jupiter is to the upper right of the moon.

Thursday: Mnemonics are helpful for remembering astronomy facts. (Similarly, “Johnny Mnemonic,” the 1995 cyberpunk film, was helpful in getting Keanu Reeves’ career going.) After all, school children around the world are learning the order of the planets by remembering, “My very excellent mother just served us nine….” Oops, I guess that one needs updating with Pluto being classified as a dwarf planet. Well, here’s one that will not need updating for tens of thousands of years: the order of the stars in the Big Dipper. Because the nighttime stars are so far away from us, their actual motion through the sky, called their “proper motion” is not noticeable over even thousands of years. That is why the constellations have remained the same since ancient times. But two stars in the Big Dipper have a proper motion large enough such that in 100,000 years; the stars will no longer make a dipper shape. You can see this simulation at the American Museum of Natural History video found at https://youtu.be/sBfUBtdo8yo. Until then, you can remember the names of the seven dipper stars in order from handle to cup by remembering this helpful advice for teens: “AM, ask mom. PM, dad.” The stars are Alkaid, Mizar, Alioth, Megrez, Phad, Merek, and Duhbe. The Big Dipper is one fist above the northern horizon at midnight.

Friday: Saturn is exactly two and a half fists above due southeast at 9:00 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. All times are Pacific Time unless noted.

The Ellensburg, WA sky for the week of September 7, 2024

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 and a half fists held upright and at arm’s length 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: July 9, 2019, July 21, 2020, August 1, 2021, August 14, 2022, and August 26, 2023. 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: “You know Aries and Cancer and Draco and Libra. Leo and Pisces and Virgo and Hydra. But do you recall, the pointiest asterism of all? Triangulum, the three-sided asterism, had a very pointy shape. And if you didn’t know it, you would say it poked an ape.” Sorry. Some stores have started sending out their Christmas catalogs and that has put me in the mood to modify some Christmas songs. Anyway, Triangulum is a small constellation between the more prominent Andromeda and Aries. Its main feature is a skinny triangle oriented parallel to and four fists above the eastern horizon at 11:30 p.m.

Monday: Fomalhaut, the southernmost bright star visible from the northern USA, is one fist above the south-southeastern horizon at 11:00 p.m. In 2008, Fomalhaut and its surroundings became the first star system with an extrasolar planet to be directly imaged. See the family photo at https://apod.nasa.gov/apod/ap081114.html.

Tuesday: While many people think they need a telescope to enjoy looking at the night sky, some objects actually look better through binoculars. Open star clusters are one of those types of objects. M39, the 39th object in Charles Messier’s catalog, is straight overhead at 11:00 p.m. This open star cluster contains about 30 stars in a region that is about seven light years across and a thousand light years away. A quick trigonometry calculation shows that the cluster is about the same size as the full moon in the night sky. Read more about M39 at https://stardate.org/radio/program/2022-09-04.

Wednesday: At 1:00 a.m., Jupiter, the brightest point of light in the sky at this time, is one and a half fists above the east-northeastern horizon. Mars is a fist to the lower left of Jupiter.

Thursday: Earlier this week, you read about Fomalhaut, the second brightest star with a planet. The brightest star known to have a planet is Pollux, in the constellation Gemini. (First vs. second brightest is meaningless here because they are nearly identical in magnitude, 1.15 vs. 1.16.) Pollux is four and a half fists above due east at 5:30 a.m., right below its “twin” star Castor. Read more about Pollux at https://goo.gl/cL5t9p.

Friday: Arcturus is two fists above the western horizon at 9:00 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. All times are Pacific Time unless noted.

The Ellensburg, WA sky for the week of August 17, 2024

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 and to the right 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 10:15 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: The August full moon is traditionally called the full sturgeon moon by Midwest and northeastern Native American tribes because the lake sturgeon in this part of the country were easiest to catch during this full moon time. This month’s full moon is a supermoon, meaning it occurs close to perigee and appears large in the sky. Read all about Supermoon-mania at https://earthsky.org/human-world/what-is-a-supermoon.

Tuesday: Saturn is about a thumb width to the upper right of the moon at 10:00 p.m. They are one fist above the east-southeastern horizon.

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 https://www.jpl.nasa.gov/news/kepler-watches-stellar-dancers-in-the-pleiades-cluster. See the Pleiades for yourself, about a half a fist above the east-northeastern horizon at 11:30 p.m.

Thursday: 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 11:00 p.m.

Friday: The bright planet Jupiter is five fists above the east-southeastern horizon at 5:30 a.m. Mars is about a half a fist to the lower left of Jupiter.

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. All times are Pacific Time unless noted.

The Ellensburg, WA sky for the week of August 10, 2024

Saturday: The Perseid meteor shower peaks over the weekend with the peak of the peak coming Sunday night/Monday morning. 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 moon is in the first quarter phase this weekend so it sets at about midnight. 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 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.

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 about 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 and Mars are four fists above the east-southeastern horizon. Mars is a little bit above Jupiter. Over the next two days, Mars will move down past Jupiter.

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 three 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 a little on the northwest side of straight overhead at 10:00 p.m. In case you didn’t get up at 5:00 a.m. yesterday to look for Saturn, you can find it about a half a fist above the east-southeastern horizon at 10:00 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 midnight, 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.

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. All times are Pacific Time unless noted.

The Ellensburg, WA sky for the week of August 3, 2024

Saturday: Star light. Star bright. The first star you see tonight might be Vega, nearly seven fists held upright and at arm’s length above the eastern horizon right after sunset.

Sunday: The moon is almost directly between the Earth and the Sun tomorrow. That means you won’t be able to see it. But that does not mean it doesn’t exist. Contrary to the belief of toddlers and immature politicians, just because you can’t see something doesn’t mean it doesn’t exist. (Note a double negative statement followed by a triple negative statement. I’m not unsorry about that.) Now, back to the science. What would happen to the Earth if the moon really didn’t exist? In that 2013 blockbuster Oblivion, aliens destroy the moon and Tom Cruise survives. In real life, the long-term effects on the Earth would be devastating to life as we know it. The moon stabilizes the spin axis of the Earth keeping the seasons fairly uniform over time. For more information on what would happen to the earth if the moon were destroyed, go to https://www.popsci.com/what-would-happen-if-moon-suddenly-disappeared/. For more information on Thomas Cruise Mapother IV, go to http://en.wikipedia.org/wiki/Tom_Cruise.

Monday: The moon, Venus, and Regulus - from brightest to dimmest - are just above the west-northwestern horizon at 9:00 p.m.

Tuesday: Saturn is about one fist above the east-southeastern horizon at 11:00 p.m.

Wednesday: The Gemini twins, first Castor and then Pollux, rise just before the Sun. At 5:00 a.m., Pollux is one and a half fists above the 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.

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 about six fists above due south at 11:20 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: Jupiter, Mars, and the bright star Aldebaran make a small triangle about four fists above the eastern horizon at 5:00 a.m. Jupiter is the brightest of the three. Mars is just to the upper right of Jupiter.

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. All times are Pacific Time unless noted.

The Ellensburg, WA sky for the week of July 27, 2024

Saturday: Mercury and Venus are low on the west-northwestern horizon right after sunset. Venus is the brighter of the two. Mercury is a fist to the left of Venus at 9:10 p.m. The star Regulus is to the upper right of Mercury.

Sunday: Have you ever planned a vacation to a place because it was supposedly the up-and-coming locale? Then, when the vacation time finally arrives, you find out the place doesn’t live up to its billing. Seven years ago this month, astronomers strengthened earlier findings that the star Tau Ceti, one of our closest neighbors at 12 light years away, has four planets classified as “super-Earths”. Two of the planets are in the so-called habitable zone where the temperature is just right for having liquid water on their surface. Time for a va-ca-tion! Well, not so fast. Astronomers have only a lower limit to the planet masses so they may be too massive for complex life to form. And the Tau Ceti system has ten times as much mass in dust and rocks as our own solar system. So you’ll want to do some research before you travel there. Tau Ceti is one and a half fists above the southeast horizon at 3:00 a.m. For more information about the discovery, go to https://skyandtelescope.org/astronomy-news/four-exoplanets-may-orbit-nearby-sun-like-star/.

Monday: The Southern Delta Aquarid meteor shower peaks tonight and on into mid-August. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Aquarius near the star Delta Aquarii, also known as Skat. This point is about one and a half fists above the southeastern horizon at 1:00 am tonight. You can follow this point throughout the night, as it will remain a fist above Fomalhaut, the brightest star in that section of the sky, and a first to the lower right of Saturn. The Moon is approaching the new moon phase this week meaning it will not be up for many hours each night. For more information about this year’s shower, go to https://earthsky.org/?p=159138. As your mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere.

Tuesday: Clockwise from the top, the moon, Mars, the star Aldebaran, and Jupiter make a crooked diamond shape three and a half fists above due east at 5:00 a.m.

Wednesday: The bright star Altair is four fists above the southeastern horizon at 10:00 p.m.

Thursday: Mizar is a well-known binary star in the constellation Ursa Major. You can find it at the bend in the Big Dipper handle, three fists above due northwest at midnight. Its name is Arabic for waistband. Mizar has an optical double called Alcor, which is less than a pinky width away and can easily be seen with the naked eye. Optical doubles are stars that are close together in the sky but do not orbit a common center of mass as true binary stars. Not wanting to deceive sky gazers who call Alcor and Mizar a binary star, two stars that DO orbit a common center of mass, Mizar actually is a binary. It was the first binary star system discovered using a telescope. Mizar A and Mizar B are about 400 astronomical units apart from each other and about 80 light years from Earth. 400 astronomical units is about 10 times the distance between the Sun and Pluto.

Friday: The Perseid meteor shower peaks in a week and a half. But there will be an increased number of meteors over the next two weeks. If the Moon is out when you want to look, position yourself so you are in the Moon’s shadow. 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 held upright and at arm’s length above the northeast horizon at 11:00 p.m. By dawn, 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 about 11 p.m. to dawn for the next two weeks in about the same location in the sky.

The Perseid shower is one of the longest lasting showers. For tips about optimizing your viewing this year, go to https://earthsky.org/?p=165416  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. All times are Pacific Time unless noted.