The Ellensburg WA sky for the week of 3/31/18

Saturday: The first day of spring was March 20. The most recent full moon is today. That means tomorrow 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 pretty 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 a half a fist held upright and at arm’s length above the east-southeast horizon at 9 p.m., just to the lower right of the Moon. To learn how to calculate the exact date of Easter for any year, go to https://www.assa.org.au/edm.   

Sunday: Mars and Saturn are right next to each other in the morning sky this entire week. This morning, the slightly brighter Mars nearly two fists held upright and at arm's length above the south-southwest horizon. Saturn is about a thumb width above Mars. Right below Mars, and visible with binoculars, is one of the brightest globular clusters in the sky, M22. 

Monday: Jupiter is more than a half a fist below the Moon at 11:30 p.m. By 6:00 a.m., they are in the southwest sky and less than a half a fist apart. See if you can notice the difference in their distance apart from each other. 

Tuesday: The Space Shuttles have been retired. But NASA is still making plans about the future of space flight. Here is a small NASA poster summarizing the future of American Human spaceflight: https://goo.gl/Gd3q9q. It is interesting to compare the sizes of these real spaceships to the dozens of fictional spacecraft summarized on a poster found at http://goo.gl/F95aEL. Next time you are in Seattle, go see the Full Fuselage Space Shuttle Trainer at The Museum of Flight (http://www.museumofflight.org/). 

Wednesday: Venus is one fist above the west horizon at 8:15 p.m. 

Thursday: April, Global Astronomy Month, is a great time to look at space.... art. Numerous experts and space art enthusiasts will be talking about and showing the work of space art pioneer Chesley Bonestell at a Facebook Live event. For more information, including a ling to register for the free event, go to https://goo.gl/jCgxgt. 

Friday: You need to get up early tomorrow to cheer on your favorite runners at the Yakima River Canyon Marathon starting at 8 a.m. on Canyon Road just south of Berry Road. So why not get a little viewing in? To symbolize the long trail of a marathon, follow the long trail of our own Milky Way Galaxy. It seems to rise up from the ground due south. It its highest, it is five fists above due east. It sinks back to the ground due north. The thickest part of the Milky Way is in the southern sky because that is the direction of the center of the galaxy.
The CWU Physics Department and the College of the Sciences is hosting its monthly First Saturday planetarium show tomorrow from noon to 1 pm. Physics major Jessica Kisner will give a presentation about Mars. The huge images on the dome will almost make you feel like you are on Mars! The show is free and open to all ages. There will be a show at noon on the first Saturday of every month hosted by different CWU astronomers and astronomy educators. The planetarium is room 101 in Science Phase II, just off the corner of 11th and Wildcat Way, H-11 on the campus map found at https://www.cwu.edu/facility/campus-map.

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 3/24/18

Saturday: Has there ever been life on Mars? Astronomers don’t know. But the Mars Curiosity Rover has been digging up some strong evidence that Mars was hospitable to life in the past. At the end of 2012, the first drilling assignment for Curiosity found clay-like minerals that form in the presence of water. In December 2013, scientists announced the strongest evidence yet for an ancient fresh-water lake in Gale Crater. Planetary geologist John Grotzinger said that Earth microbes could have thrived in this lake if they were placed there. Last year, astronomers at the European Southern Observatory’s Very Large Telescope in Chile found evidence that Mars was once had an ocean that held more water than the Arctic Ocean and covered a greater percentage of Mars’ surface than the Atlantic Ocean does on Earth. Finally, last month, Curiosity used its new drilling technique to drill into a Mars rock for the first time in 15 months. Watch a short video about the new drilling technique at https://goo.gl/u6N7N1 Watch reddish Mars, itself, two fists held upright and at arm’s length above the south-southeast horizon at 6:30 a.m. Yellowish Saturn is about a half a fist to the left of Mars. They will move closer together in the sky over the next few days. 

By the way, the name of the observatory in Chile really is Very Large Telescope. See for yourself at http://www.eso.org/paranal.  

Sunday: Astronomers are often fascinated with large objects. Planets that could fit 1000 Earths (Jupiter). Stars that would fill up the entire inner Solar System (Betelgeuse). Galaxies with 400 billion stars (Milky Way). But what about the smallest objects? One of the smallest stars is Proxima Centauri, the closest known star other than our Sun. It is about 12% of the mass of the Sun. Last year, astronomers even announced the discovery of an Earth-sized planet orbiting Proxima Centauri indicating that even very small starts can have planets. The smallest theoretically possible star would be about 7.5% of the mass of the Sun. Any smaller and it could not support fusion reactions. For more on small stars, go to http://goo.gl/EHBdOX. 

Jupiter, the object that will fit 1000 Earths is a half a fist above the east-southeast horizon at midnight. 

Monday: Orion still has a prominent spot in the nighttime sky. The belt is three fists above due southwest at 9 p.m. 

Tuesday: Venus is one fist above the west horizon at 8 p.m. Use Venus and a pair of binoculars to try spot the planet Uranus. First, find Venus with your binoculars. With Venus at the center of the field of view, Uranus will be to the upper left, less than half way from Venus to the edge of the field of view. Don't be disappointed if you can't find it. The setting Sun and the atmosphere will make it tricky. 

Wednesday: April is Global Astronomy Month (GAM). While many astronomy experiences come from looking up, you can also experience astronomy looking down… at pen and paper. GAM has numerous arts initiatives and is looking for contributors. Even if you’ve never written a poem before, this is your opportunity to express your love for astronomy in a unique way and possibly share it with others. Go to https://astronomerswithoutborders.org/gam2018-programs/astroarts.html for more information about the AstroPoetry and AstroArt contests. The AstroPoetry Contest has already started so don't delay! 

Thursday: If the National Enquirer was around in Galileo’s day, it may have featured the headline: “Saturn has love handles; Opis leaves him for a much hotter starlet”. When Galileo first observed Saturn through a telescope, he reported objects that looked like bulges on either side of Saturn’s midsection. He was actually seeing Saturn’s rings through less than ideal optics. Saturn is two fists above the south-southeast horizon at 6 a.m., about two finger widths to the left of the slightly brighter Mars. 

Friday: If you recently promised to do something "once in a Blue Moon", it is time to pay up. Tonight's Full Moon is the second full moon of the month, which some sources call a Blue Moon. If you don't want to do what you promised, you will want to quote the historical Blue Moon definition which states a Blue Moon is the third Full Moon in a season with four Full Moons. By this definition, the next Blue Moon is May 18, 2019. For more about Blue Moons, go to .https://www.space.com/15455-blue-moon.html.  

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 3/17/18

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, three days before the first day of spring, 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 is 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: The Moon, Venus, and Mercury make a small triangle a little less than a fist held upright and at arm's length above due west at 7:45 p.m. Bright Venus is at the apex of the triangle and Mercury is at the upper right. 

Monday: The Milky Way is pretty easy to spot on 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. Look due south at 9 p.m. Follow the fuzzy path just to the left of the bright star Sirius two fists above the horizon, to the right of the bright star Procyon four and a half fists above the south horizon, through Capella six fists above the west horizon, through W-shaped Cassiopeia three fists above the northwest horizon, and down to due north where the bright star Deneb sits just above the horizon. 

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 9:15 a.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 actually 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: At 6 a.m., Saturn and Mars are both one and a half fists above the south-southeast horizon. 

Thursday: Jupiter's atmospheric winds are much deeper and longer lasting than those on Earth, according to data from NASA's Juno mission. This mission has taken exceptionally close and detailed images of Jupiter, including a "family" of nine cyclones near the north pole. Even Jupiter's gravity is pattern is mush stranger than originally thought. For more information about these findings, as well as breathtaking images, go to https://goo.gl/u1ve1w. For more information about Jupiter, stay up until midnight and look just above the east-southeast horizon. Or get up at 6:30 a.m. and look two fists above the south-southwest horizon. 

Friday: 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 9:32 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. 

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.