Wednesday, March 27, 2024

The Ellensburg, WA sky for the week of March 30, 2024

Saturday: Many artists have sung the song “Blue Moon”. But few have sung the song “Blue Planet”. It goes, in part “Blue Planet, you saw me standing with 28 others. Rolling around like a barrel. Without a worry or care-L.” It’s about the planet Uranus, which orbits the Sun in a rolling motion and has 28 moons. Every one of Uranus’ moons is named after characters in works by William Shakespeare or Alexander Pope. Uranus is relatively easy to find tonight and will get easier to find over the next two weeks. It is three fists held upright and at arm’s length above the western horizon at 8:00 p.m., easily visible with binoculars. First find Jupiter, a little more than two and a half fists above the western horizon. With Jupiter at the bottom of your field of view, Uranus will be at the top of your field of view. Return to this same spot for the next few nights. If the point you are looking at moves compared to the neighboring points of light, you are looking at Uranus. Over the next three weeks, Uranus and Jupiter will move towards each other in the evening sky.

Sunday: The first day of spring was March 19. The most recent full moon was March 24. That means today is Easter. The standard way to determine the date of Easter for Western Christian churches is that it is the first Sunday after the full moon that occurs on or after the vernal equinox, also known as the first day of spring. Of course, the other standard way is to look for the date of church services celebrating the resurrection of Jesus. There is no Bible story of an “Easter star”. If there were, Spica would be a good choice. The name Spica comes from the Latin “spica virginis” which means “Virgo’s ear of grain”. Spica represents life-giving sustenance rising after a long winter just like the risen Jesus represents life-giving redemption to Christians. Spica is two fists above due southeast horizon at 9:00 p.m. For an algorithm on how to calculate the exact date of Easter for any year, go to https://www.rmg.co.uk/stories/topics/when-easter.

Monday: Global Astronomy Month (GAM) starts this week. Go to https://my.astronomerswithoutborders.org/programs/global-astronomy-month for more information about events. If you want to take a chance on a spur of the moment event, visit their Facebook page: https://www.facebook.com/astronomerswithoutborders/.

Tuesday: Within the next few months, astronomers think a new star will form in the constellation Corona Borealis. This constellation is about three fists above the eastern horizon at 11:00 p.m. The new star will form just below the brighter curve-shaped line of stars that gives the constellation its name.

Wait a minute. Stars take millions of years to form. This must be some sort of April Fool’s joke.

No Joke. The star T Coronae Borealis, abbreviated T CrB, is a two-star system in which a white dwarf and a red giant orbit a common center of mass. For about 80 years, the white dwarf star pulls mass from the red giant. When it pulls in a certain amount of matter, the matter ignites in a chain reaction nuclear explosion that lasts for many Earth days. When this happens, the normally very dim pair of stars get bright enough to be seen with the naked eye. Based on the details cataloged by astronomers during previous ignitions, as well as recent measurements, the next event should occur between now and September. The general name for this type of “new star” is a nova.

By now you’ve learned that the star is not really new, just newly, and temporarily, bright. This star will get higher in the sky earlier as the weeks go by, making it easier to see. Memorize the shape of Corona Borealis so you’ll notice when it is different. For more information about T CrB, go to https://www.scientificamerican.com/article/this-nova-will-soon-erupt-as-a-once-in-a-lifetime-new-star-in-the-night-sky/.

Wednesday: It is time to start getting ready for next Monday’s total solar eclipse. Everyone in the lower 48 states in the USA will be able to see at least a partial solar eclipse. Make sure you watch it safely. The American Astronomical Society (AAS) and Big Kid Science have teamed up to make a simple and useful app called Totality. It shows the path superimposed on a USA map, provides the exact time of the event in your location, as well as a model of the shadow path. Go to https://eclipse.aas.org/totality for more information on how to download.

In addition, the AAS has a list of safe solar viewing techniques and tools, including disco balls. Go to https://baas.aas.org/science-in-the-shadow-safe-ways-to-view-the-sun for more safe solar tips. If you use these tips, your eyesight will be “Stayin’ Alive”.

Thursday: Last week you looked at something fuzzy, the Milky Way. So, reward yourself tonight by looking at something sharp and detailed. The OSIRIS-REx mission sent back the highest resolution global map of any Solar System object, the asteroid Bennu. Using pictures taken from just three to five kilometers above the surface, the map has a resolution of five centimeters per pixel, the most detailed map of any object other than Earth. Go to https://www.asteroidmission.org/bennu_global_mosaic/ to download the map.

Friday: At 6:00 am tomorrow morning, the moon, Saturn, and Mars line up diagonally from the eastern horizon.

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.

Thursday, March 21, 2024

The Ellensburg, WA sky for the week of March 23, 2024

Saturday: Did you get binoculars for the holidays? Like Celebrate Scientists Day or Science Education Day (both March 14)  If so, start using them on some of the easy to find binocular targets found here: https://earthsky.org/astronomy-essentials/best-targets-for-binoculars-moon-planets-nebula-clusters/. The first item on the list, the Moon, is a wonderful choice this week because it is full this week, meaning it is out all night. One of my favorite binocular objects is the Hyades Open Star Cluster. It is a V-shaped set of stars found about four fists held upright and at arm’s length above the western-southwestern horizon at 8:00 p.m. The bright star Aldebaran is in the upper left-hand portion of the V, just below Aldebaran is the double star system Theta1 and Theta2 Tauri. Theta2 Tauri is a blue giant star and Theta1 Tauri is an orange giant star. Through binoculars, you should get a hint of their color. In the mythology of the Maya, the Theta Tauri pair is known as Chamukuy, meaning “small bird” in the Yucatec Maya language.

Sunday: 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 next few weeks. Mercury is one fist above western horizon at 8:00 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. By mid-May, it will be barely visible in the morning sky.

Earlier in the week, I invited you to use binoculars to observe the moon. Tonight, I challenge you to use your unaided eyes to notice the subtle dimming of the full moon. It is dimmer because the moon will pass through the partial or penumbral shadow of the Earth starting at 9:53 p.m. Pacific Daylight Time. Maximum dimming occurs at 12:13 a.m. at mid-eclipse. This is a very minor eclipse. But eclipses always come in pairs. And the partner to this one is a biggie: the total solar eclipse that will pass over North America from western Mexico through eastern Canada on April 8.

Monday: Jupiter is nearly two fists above the western horizon at 9:00 p.m.

Tuesday: Spica is about a half a fist to the upper right of the moon at 10:00 p.m.

Wednesday: Mars is less than a half a fist above the east-southeastern horizon at 6:15 a.m.

Thursday: Signs of spring: flower buds, leaves on the trees, beetle larvae, and the Spring Triangle. The bright stars Regulus, Arcturus, and Spica rise as evening starts. By 10:00 p.m., Regulus is five and a half fists above the south-southeastern horizon, Arcturus is two and a half fists above due east, and Spica is one fist above the east-southeastern horizon. For more on the Spring Triangle, go to http://tiny.cc/ep7vtz.

Friday: The Milky Way is pretty easy to spot in the early spring sky. Just look up. Everything you see in the sky, including that bird that just startled you, is in the Milky Way. But even the path of densely packed stars in the plane of our galaxy that look like a river of milk is easy to find. Face due west at 9:00 p.m. in a fairly open area. The fuzzy Milky Way path starts due south, moves upward past the bright star Sirius, near Mars, towards the bright star Capella, through W-shaped Cassiopeia and down to due north where the bright star Deneb sits just above the horizon.

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.

Thursday, March 14, 2024

The Ellensburg, WA sky for the week of March 16, 2024

 Saturday: Ask someone which day in March has the same duration day and night. Go ahead, ask someone. Why are you still reading this? I can wait. If that person said the first day of spring, they are wrong. Today, a few days before the first day of spring, is the date in which day and night are closest in duration in central Washington. 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 already below the horizon. This makes the Sun appear to rise before it actually rises and appear to set after it actually sets. Second, spring starts when the center of the Sun passes through the point called the vernal 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 spring would still be longer than 12 hours.

Sunday: Mercury is about a half a fist held upright and at arm’s length above the western horizon at 8:00 p.m.

Monday: Pollux is about a thumb width above the moon and Castor is about a first to the upper right of the moon at 10:00 pm. They are more than six fists above the southwestern horizon at this time.

Tuesday: Look up in the sky. It’s a plane. It’s a bird. No, it’s the vernal equinox. The vernal equinox!? Spring starts at 8:00 p.m. Pacific Daylight Time. The first day of spring is often called the vernal equinox. This label for the day is misleading. The vernal equinox is the point in the sky where the Sun’s apparent path with respect to the background stars (called the ecliptic) crosses the line that divides the stars into northern and southern celestial hemispheres (called the celestial equator). This point is in the constellation Pisces the fishes. At the vernal equinox, the Sun is moving from the southern region of background stars to the northern region.

Because the Earth slowly wobbles like a spinning top, the vernal equinox is slowly moving into the constellation Aquarius. By the year 2597, the vernal equinox will reach the constellation Aquarius and the “Age of Aquarius” will begin. Until then, we’ll be in “the age of Pisces”.

Wednesday: Many artists have sung the song “Blue Moon”. But few have sung the song “Blue Planet”. It goes, in part “Blue Planet, you saw me standing with 28 others. Rolling around like a barrel. Without close sisters or brothers.” It’s about the planet Uranus, which orbits the Sun in a rolling motion and has 28 moons. 25 of Uranus’ moons are named after characters in works by William Shakespeare and three are from the poem “The Rape of the Lock” by Alexander Pope.

Typically, Uranus is difficult to find. For the next few weeks, Uranus will be moving towards the much brighter Jupiter. Tonight, Uranus is a half a fist above Jupiter. View these two bodies for the next few nights. Jupiter is easy to identify. If the dimmer point of light you are looking at moves compared to the neighboring dim points of light, you are looking at Uranus.

Thursday: If you want to put somebody off, tell her or him to wait until Deneb sets. At Ellensburg’s latitude of 47 degrees, Deneb is a circumpolar star meaning it never goes below the horizon. At 9:45 p.m., it will be as close as it gets to the horizon, about two degrees above due north. Watch it reach this due north position about 4 minutes earlier each night.

Friday: If you know exactly where to look in the sky, you can see a few bright planets when the Sun is out. The Solar and Heliospheric Observatory, or SOHO, is always watching the sky when the Sun is out… because it is always watching the Sun! Most of the SOHO images are filtered images of the Sun’s photosphere, the top of the visible layer. But two images, the LASCO C2 and C3, place a mask over the Sun in order to observe the Sun’s corona as well as solar system objects that pass near the Sun. For the next few days, For more about using SOHO to observe Solar System objects, go to https://skyandtelescope.org/astronomy-news/planets-and-comets-cant-hide-from-sohos-eye/.

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.

Wednesday, March 6, 2024

The Ellensburg, WA sky for the week of March 9, 2024

Saturday:  Don't forget to set your clocks ahead one hour tonight for the annual ritual called daylight savings. Daylight savings originated in the United States during World War I to save energy for the war effort. But a recent study by two economists shows that switching to daylight savings time may actually lead to higher utility bills. When the economists compared the previous few years of energy bills in the section of Indiana that just started observing daylight savings, they discovered that switching to daylight savings cost Indiana utility customers $8.6 million in electricity. In an even more important consequence of daylight savings, Stanley Coren of the University of British Columbia discovered a 7% jump in traffic accidents on the Monday after we "spring ahead". Blame it on the lost hour of sleep. And sky watchers will lose even more sleep because the sky stays light for an additional hour.

Sunday:  A super moon occurs when the full moon is relatively close to the Earth. The ‘super” aspect refers to its apparent size in the sky. But super can also refer to its gravitational pull because the closer the moon to the earth, the greater the gravitational pull and the treater the tides. In that case, tonight’s new moon is a super moon because it is relatively close to the Earth. Of course, since it is a new moon, the lit side is facing away from us, and we can’t see it. But the Earth, and the ocean tides, can feel its pull.

Monday: Avast ye matey. Swab the poop deck. Pirates love astronomy. In fact, the term “poop” in poop deck comes from the French word for stern (poupe) which comes from the Latin word Puppis. Puppis is a constellation that represents the raised stern deck of Argo Navis, the ship used by Jason and the Argonauts in Greek mythology. Argo Nevis was an ancient constellation that is now split into the constellations Puppis, Vela, and Carina. The top of Puppis is two fists held upright and at arm’s length above due south and about a fist and a half to the left of the bright star Sirius at 9:45 p.m. Zeta Puppis, the hottest, and thus the bluest, naked eye star in the sky at 40,000 degrees Celsius, is about a half a fist above due south at this time.

Tuesday: “Oooo, they’re little runaways. Orion’s stars moved fast. Tried to make a getaway. Ooo-oo, they’re little runaways,” sang Bon Jovi in his astronomical hit “Runaway”. At least that’s what I hear when I listen to the song. After all, it fits the recently calculated trajectory of AE Aurigae, Mu Columbae, and 53 Arietis. Extrapolating the actual motion of these three stars back in time, they were all in the location of the star-forming region called the Orion Nebula a few million years ago. What kicked these stars out? Not paying rent? Excessive partying? No, it was simply gravitational interactions with near-by stars. Find out more about the eviction at http://goo.gl/UeLwKQ. The Orion Nebula is visible with the naked eye from a very dark site, about two and a half fists above the southwestern horizon at 10:00 p.m.

Wednesday: Jupiter is right below the crescent moon at 8:00 p.m. They are nearly four fists above the western horizon.

Thursday: Mercury is coming out of hiding from the Sun’s glare. It is visible less than a half a fist above the western horizon at 8:00 p.m.

Friday: “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 very bad spy movie dialogue is 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 southeastern horizon at 9:30 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.

Friday, March 1, 2024

The Ellensburg, WA sky for the week of March 2, 2024

Saturday: Tonight is a great night to look for the Big Dipper. Tomorrow will be a great night to look for the Big Dipper. In fact, every night for many centuries will be great nights to look for the Big Dipper. But the Big Dipper’s shape slowly changes over many, many, many, many centuries. (Have I reached my word count yet?) Tens of thousands of years ago, it didn’t look like a dipper and tens of thousands of years from now, it will no longer look like a dipper. For a short video simulation of the changing Big Dipper, go to https://youtu.be/txJH8RlIoXQ. For a look at the current Dipper, face northeast at 8:00 p.m. The lowest star, Alkaid, is two and a half fists held upright and at arm's length above the horizon. 

Sunday: March to-do list: 1) Move clocks ahead an hour for daylight saving time, 2) Start spring cleaning, 3) Discover exoplanets. Hmm. One of these is not like the other. NASA has set up a program through which you can learn about exoplanets, observe exoplanets, analyze their data, and submit it to a repository for astronomers to use for their research. Exoplanets are any planets outside our solar system. For more information about this project, go to https://exoplanets.nasa.gov/exoplanet-watch/.

Monday: On these late winter mornings, it is still difficult to get going. You just want to plop into a chair and sit still. But are you really sitting still? You’re moving at about 700 miles per hour due to the rotation of the Earth on its axis and 66,000 miles per hour due to the revolution of the Earth around the Sun. If that’s not enough, the entire solar system is orbiting the center of the galaxy at a whopping 480,000 miles per hour! So, while you may be sitting still with respect to your living room (and all the overachievers in your house), you are NOT sitting still with respect to the center of the galaxy. For more information about this concept, go to https://nightsky.jpl.nasa.gov/docs/HowFast.pdf

Tuesday: Deneb is two and a half degrees above the due north horizon. You can barely fit your thumb between them.

Wednesday: If you ask an astrobiologist for the three most likely places to find evidence of life in the Solar System, other than Earth, they’d probably say Mars, Europa (“Didn’t they sing “The Final Countdown”?”), and Enceladus. Mars makes sense because you know scientists have sent a lot of probes there. Enceladus, one of Saturn’s moons, is an up-and-coming interest that first piqued astrobiologists’ interest a few years ago when NASA’s Cassini probe discovered jets of water containing organic materials shooting out. Between the pop culture alien hot spot of Mars and the new favorite is Jupiter’s moon Europa. Astronomers first discovered strong evidence of a large water ocean on Europa in 1989 during a Galileo flyby. In the next five years, NASA and the European Space Agency (ESA) will be sending spacecraft to Europa. For a preview of the ESA JUICE mission and the NASA Europa Clipper mission, go to https://youtu.be/dAW2uPPS2A4. Only Jupiter is visible in the evening sky for the next few months. It is three and a half fists above the west-southwestern horizon at 7:00 p.m.

Thursday: From left to right, Venus, Mars, and the moon are low on the east-southeastern horizon at 6:00 am

Friday: The bright star Arcturus is nearly three fists above due east 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.