Friday, July 12, 2019

The Ellensburg WA sky for the week of July 13, 2019

Saturday:  Jupiter is a half a fist to the right of the Moon in the southern sky at 10 p.m. Since this week marks the fiftieth anniversary of the Apollo 11 mission, it is fitting that the Moon will be prominent in the night sky all week. Warm up for the week by reading 50 Apollo 11 facts at http://mentalfloss.com/article/585759/apollo-11-moon-landing-facts

Sunday: Four years ago today, NASA’s New Horizons probe passed by Pluto. If the band Nirvana was still together, they’d probably rewrite one of their hit songs to be called Heart-Shaped Spot, after one of Pluto’s most distinctive features. “She eyes me like a dwarf planet when I am weak. I’ve been imaging your heart-shaped spot for weeks.” Astronomers think this heart-shaped spot is a large plain of nitrogen ice that consists of convective cells 10-30 miles across. Solid nitrogen is warmed in the interior of Pluto, becomes buoyant, and bubbles up to the surface like a lava lamp. You will find great pictures and information about what New Horizons found this past year at http://pluto.jhuapl.edu/. Pluto, itself, is one fist held upright and at arm’s length above the southeastern horizon, a half a fist to the lower left of the much brighter Saturn.
Hey, wait, I’ve got a new complaint. People should be more interested in astronomy. Hopefully all of the Apollo 11 news will help build this interest in more people.

Monday: Saturn is in the southeastern sky,  about a thumb width to the left of the Moon at 10 p.m. In a few decades, future generations may be celebrating the first Saturn Moon landing just like we are celebrating the first Earth Moon landing. Last month, NASA announced the first step in the process: an innovative mission to send a flier, nicknamed the Dragonfly, to explore diverse parts of Titan. The Dragonfly, launching in 2026 and landing in 2034, will analyze samples from various dunes and craters to study the past and present chemical processes on Titan. For more information about the mission, go to https://www.nasa.gov/press-release/nasas-dragonfly-will-fly-around-titan-looking-for-origins-signs-of-life. Titan is visible through a pair of 10X50 binoculars tonight, about Saturn-ring-diameters to the left of Saturn.

Tuesday: Tonight’s Moon is full. This is a great opportunity to really study our nearest neighbor. Download the Skywatcher’s Guide to the Moon at https://nightsky.jpl.nasa.gov/docs/ObserveMoon.pdf. It shows some of the largest features as well as the location for each of the six human Moon landings.

Wednesday: Say "Cheese". 169 years ago today, Vega, in the constellation Lyra the lyre, became the first star ever photographed. The photograph was taken at the Harvard Observatory using the daguerreotype process. Vega is the third brightest night time star we can see in Ellensburg, behind Sirius and Arcturus. Vega is nearly straight overhead at 11:00 tonight. 

Thursday: Deneb Algedi, the brightest “star” in the constellation Capricornus is about a thumb width to the upper left of the Moon tonight. They are low in the southeastern sky at 11 p.m. The word “star” is in quotes because it makes me sound pretentious. And because Deneb Algedi, which means “the tail of the goat” (there’s that pretentiousness again) in Arabic, is actually a four star system.

Friday: Say “good-bye” to Regulus tonight, before it gets lost in the glare of the setting Sun. It is less than a half a fist above the west-northwestern horizon at 9:45 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

Thursday, July 4, 2019

The Ellensburg WA sky for the week of July 6, 2019

Today:  Say “Goodbye” to Mars before it is too late. Mars less than a half a fist held upright and at arm’s length above the west-northwest horizon at 9:30 p.m. Last month, the Mars Curiosity rover measured the highest amount of methane ever found on the Martian surface. This is relevant for the search for life because most methane on Earth is produced by living things such as microbes in the stomachs of cattle. But before you considering mooooooving to Mars, remember that some geologic processes also produce methane. Read all about Martian methane at https://www.nature.com/articles/d41586-019-01981-2

Sunday: The bright star Regulus is one fist above the west horizon at 10 p.m.

Monday: Look straight up at midnight. The head of Draco the dragon will be looking straight down on you. The brightest star in the head is called Eltanin. If you chose to wait for a VERY long time, Eltanin will be the brightest star in the night sky. Currently 154 light years away, it is moving towards Earth and will be only 28 light years away in about 1.3 million years, claiming the title as the brightest star.

Tuesday: 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 two fists above due south at 1 a.m. It is about one fist above due southeast at 10 p.m. Careful readers of this column should realize they could be doing something much more interesting. But they also may recall that Saturn is in opposition on nearly the same date every year: June 14, 2017. June 26, 2018. 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.

Wednesday: Being in a coma is a bad thing. Looking at the Coma Star Cluster is a good thing. The Coma Star Cluster is an open cluster of about 50 stars that takes up more space in the sky than 10 full Moons. It looks like a fuzzy patch with the naked eye. Binoculars reveal dozens of sparkling stars. A telescope actually diminishes from the spectacle because the cluster is so big and the telescope’s field of view is so small. The Coma Star Cluster is in the faint constellation Coma Berenices (ba-ron-ice’-ez) or Queen Berenice’s hair. Queen Berenice of Egypt cut off her beautiful hair as a sacrifice to the gods for the safe return of her husband Ptolemy III from battle. The Coma Star Cluster is about four fists held upright and at arm’s length above the west horizon at 11:00 p.m. 

Thursday: Mizar is a star in the middle of the Big Dipper handle. Don’t confuse Mizar with its rhyming brother Izar in the constellation Bootes. Izar is also a binary star with about the same apparent brightness. And both were featured in different episodes of Star Trek. Izar was featured in the Star Trek episode “Whom Gods Destroy” from the original series. It is the base of Fleet Captain Garth, a former big shot in the federation and one of Kirk’s heroes before he went insane. Garth kidnaps Kirk and Spock before eventually being outsmarted. Mizar doesn’t play as big a role in its episode. It is the star of the homeworld of one of the alien species in The Next Generation episode “Allegiance”. Izar is one fist above the bright star Arcturus and seven fists above the south horizon at 10 p.m. Mizar is seven fists above the northwest horizon at this time.

Friday: Moon, Jupiter, and Antares make an equilateral triangle in the southern sky at 10 pm. Jupiter is about one fist to the lower left of the Moon and Antares is about one fist below the Moon.


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

Thursday, June 27, 2019

The Ellensburg WA sky for the week of 6/29/19


Today:  Mercury and Mars are merrily meandering a half a fist held upright and at arm’s length above the west-northwest horizon at 9:45 tonight. Mercury is a little to the left of Mars and is the brighter of the two.

Sunday: Happy Asteroid Day (http://www.asteroidday.org/), the day we celebrate avoiding the destruction of the Earth by an undiscovered asteroid. There are a million asteroids in the Solar System with the potential to strike Earth and destroy a city. Astronomers have discovered only 1% of them. Asteroid Day is an effort to educate the public and encourage policy makers to fund this important effort. King Tut may have celebrated an ancient Asteroid Day by asking his assistants to make a dagger out of a broken-off asteroid that landed on Earth. Astronomers discovered that the blade of the knife contained much more nickel than is found in terrestrial iron, an amount consistent with iron meteorites, especially with one found in the year 2000 in the Kharga region in northern Egypt. For more information about the dagger, go to http://goo.gl/BHBivd.

Monday: Jupiter is two fists above the south horizon at 11 p.m. At this same time, Mars is one fist above the southeast horizon.

Tuesday: This is a good time of the year to find the Big Dipper. The handle is nearly straight overhead at sunset. The cup is in the northwest sky. You can always use the Big Dipper to find some other bright stars. First, follow the curve, or arc, of the Big Dipper down three fists into the southern sky. This is the bright star, Arcturus, the second brightest night time star we can see in Ellensburg. Next, continue on a straight line, or spike, another three fists down toward the south horizon to the star Spica. Spica is the tenth brightest nighttime star we can see in Ellensburg. It is known as the Horn Mansion, one of 28 mansions, or constellations, in the Chinese sky. You now know how to use the Big Dipper handle to “arc” to Arcturus and “spike” to Spica.

Wednesday: Hot enough for you? Don’t blame the Earth-Sun distance. Surprisingly, the overall temperature of the Earth is slightly higher in July, when the Earth is farthest from the Sun, than in January, when it is closest. That’s because in July, the Northern Hemisphere is tilted towards the Sun. (This is the real cause of the seasons.) The Northern Hemisphere has more land than the Southern Hemisphere. Thus, in July, the large amount of Northern Hemisphere land heats up the entire Earth about two degrees Celsius warmer than in January. In January, the watery Southern Hemisphere is tilted toward the Sun. But, water does not heat up as fast as land so the Earth is a few degrees cooler. The distance between the Earth and the Sun is its greatest tomorrow, 152.1 million kilometers. This is called aphelion from the Greek prefix “apo” meaning “apart” and Helios, the Greek god of the Sun.

Thursday: When it is sitting low in the western sky, many people mistake the star Capella for a planet. It is bright. It has a slight yellow color. But, Capella is compelling on its own, even though it is “just” a star. It is the fourth brightest star we can see in Ellensburg. It is the most northerly bright star. It is a binary star consisting of two yellow giant stars that orbit each other every 100 days. At 10 p.m., Capella is a half a fist above the north-northwest horizon. You can also use the Big Dipper to find it.  First, find the two “cap” stars on the cup of the Big Dipper, the stars on the top of the cup. Draw line from the “cap” star closest to the handle to the cap star farthest from the handle. Then, continue that line to the next very bright star, which is Capella. Thus, you can “cap” to Capella. If you can’ it tonight, don’t worry. Capella is the brightest circumpolar star meaning it is the brightest star that never goes below the horizon from our point of view in Ellensburg.

Friday: The bright star Regulus is a finger-width below the crescent moon, low in the western sky at 10 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.

Thursday, June 6, 2019

The Ellensburg WA sky for the week of 6/22/19


Today:  Nearly 400 years ago, Galileo viewed the Pleiades star cluster through his telescope and saw that the seven or so stars in the region visible to the naked eye became many more. There are two main types of star clusters. Open star clusters, like the Pleiades and the Beehive, are groups of a few dozen to a few thousand stars that formed from the same cloud of gas and dust within our galaxy. Stars in open star clusters are young as far as stars go. Globular clusters are groups of up to a few million stars that orbit the core of spiral galaxies such as our own Milky Way. One of the most well known star clusters is the globular cluster in Hercules, an object that is fairly easy to find with binoculars. First find Vega, the bright bluish star five fists above the east horizon at 11 p.m. Two fists above Vega is a keystone shape. Aim your binoculars at the upper left hand star of the keystone. The globular cluster is one third of the way to the rightmost star of the keystone. It looks like a fuzzy patch on the obtuse angle of a small obtuse triangle. If you don’t know what an obtuse angle is, you should not have told your teacher, “I’ll never need to know this stuff”.

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 and 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 about a fist above the west-northwest horizon at 9:30 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. By early August, it will be visible in the morning sky.

Monday: “Mom, I can’t sleep. It is too light out!” A poor excuse you say? Good astronomy skills, I say. The latest sunset of the year happens this week. Surprisingly, the earliest sunrise and the latest sunset do not both happen on the longest day of the year, the day of the summer solstice. The earliest sunrise occurs just before the longest day and the latest sunset occurs just after the longest day. This phenomenon relates to the angle of the Sun’s path near rising and setting. In Ellensburg, that angle is about 66 degrees near the first day of summer. Because of the Earth’s orbit, which causes the Sun’s apparent motion, the angles are not symmetric. The asymmetries in orbital angles leads to the asymmetry in rise and set times. By the way, picking a specific night to give you the “can’t sleep because it is too light out” line may just be an excuse because the sunset times change by only a few seconds each day in June. This year, the sun sets between 9:01 and 9:02 p.m. between June 22 and June 29.

Tuesday: At 11 p.m., Jupiter is two fists above the southern horizon and Saturn is one fist above the southeast horizon.

Wednesday: Four years ago astronomers using a radio telescope in Australia discovered the source of fleeting radio signal bursts that had been a mystery for 17 years. And they didn’t have to probe the depths of deep space. They only had to probe the depths of… the observatory kitchen. It turns out the signal came from opening the microwave door prematurely. Read more about The Microwave Emission here: http://goo.gl/Ftb04C. Sheldon Cooper used similar methods of science when he discovered a can opener instead of magnetic monopoles in the season three premiere of “The Big Bang Theory” http://goo.gl/kAEoOD.

Thursday: Don’t wait until a week from today to go to those wimpy firecracker shows. Find the hypergiant star Rho Cassiopeiae. Astronomers think that Rho Cassiopeiae will likely go supernova (explode) in the near future. Of course, for stars, near future might mean today. It might mean 20,000 years from now. Rho Cassiopeiae is in the constellation Cassiopeia the queen. At 11:00 tonight, Cassiopeia looks like the letter “W” about three fists held upright and at arm’s length above the northeast horizon. Rho Cassiopeiae is about a finger’s width to the right of the rightmost star in the “W”. Once you find it you’ll be thinking, “Big deal, I can hardly see it.” Although it is barely visible to the naked eye, it is actually very bright. It is the 20th most luminous star in the sky, a whopping 550,000 times more luminous than the Sun.

Friday: Star light. Star bright. The first star you see tonight might be Arcturus, six fists above the south horizon right after sunset.

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 6/15/19


Today:  Tomorrow is Father’s Day, the day to celebrate the person who made you a father. No, not her. You celebrated her last month. (You didn’t forget, did you?!) Celebrate your child by getting her/him the book “Woman in Science” by Rachel Ignotofsky (http://www.readwomeninscience.com/). This creatively drawn book highlights the contributions of 50 pioneers of science from Hypatia to Katherine Johnson, the main character in the recent movie “Hidden Figures”.

Sunday: You’ve seen all of the top 100 lists: top 100 ways to use Super Glue, top 100 Thai restaurants in Ellensburg, etc. Now get excited for this week’s full Moon by reading about and finding some of the lunar 100 at 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 10:00 p.m. when the Moon is one and a half fists held upright and at arm’s length above the southeast horizon. 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. If you are wondering about that bright point of light about a half a fist to the right of the Moon, it’s Jupiter.

Monday: Summer is nearly here. How do I know? Because the days are very long. Because the temperature is rising. Because kids are getting out of school. Also, because the Summer Triangle is fairly high in the eastern sky at 11 p.m. Vega, the third brightest star visible from Ellensburg, is about six fists above the east horizon. Deneb, at the tail of Cygnus the swan is about four fists above the east-northeast horizon. The third star in the triangle, Altair in Aquila the eagle, is two and a half fists above the east horizon.
If you want to put somebody off, tell her to wait until Deneb sets. At Ellensburg’s latitude of 47 degrees, Deneb is a circumpolar star meaning it never goes below the horizon.

Tuesday: Saturn is less than a half a fist above the Moon at 11 p.m. They are both just barely above the southeast horizon.

Wednesday: Mercury and Mars are right next to each other in the evening twilight sky this week. Mercury is about four times brighter than Mars. They are about a fist above the west-northwest horizon at 9:30.

Thursday: I hope that you have never been in a collision. It can be scary and dangerous. The biggest collision in our celestial neighborhood will occur in a few billion years when our Milky Way Galaxy will collide with the Andromeda Galaxy. Here’s an article about what it will look like: https://www.universetoday.com/141750/this-is-what-itll-look-like-when-the-milky-way-and-andromeda-galaxies-collide-billions-of-years-from-now/. If you can’t stay up a few billion years to see the collision, stay up until late at night to see the Andromeda Galaxy,. First find the Great Square of Pegasus. At 2:30 a.m., the left hand corner of the square is about three fists above the east-northeast 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 nearly a trillion stars and is 2.2 million light years away.

Friday: Early this morning, the summer solstice occurs. This is when the Sun reaches its highest declination (the official name for sky latitude) of 23.5 degrees above the celestial equator. The celestial equator is the line that divides the northern sky from the southern sky. In Ellensburg, the Sun is about seven fists held upright and at arm’s length above the south horizon at 1:00 p.m. (noon standard time). Contrary to popular belief, the Sun is never straight overhead in Ellensburg or anywhere else in the 48 contiguous states. The northernmost portion of the world where the Sun can be directly overhead is 23.5 degrees north latitude. In ancient times, the Sun was in the constellation Cancer the crab on the first day of summer. Hence, 23.5 degrees north latitude has the nickname "Tropic of Cancer". Because the Earth wobbles like a spinning top, the Sun's apparent path through the sky changes slightly over time. Now, the Sun is in the constellation Taurus the bull on the first day of summer. However, citing the high cost of revising all of the science books, geographers are not changing the name of 23.5 degrees north latitude to "Tropic of Taurus". The first day of summer is often called the summer solstice. However, astronomers refer to the summer solstice as the point in the sky in which the Sun is at its highest point above the celestial equator. Thus, summer starts when the Sun is at the summer solstice point. This year, that happens at 7:56 a.m. Pacific Daylight Time.

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 6/8/19


Have you bought your favorite CWU graduate a graduation gift yet? Why not get her or him a star? I don’t mean from one of those organizations that offer to “register the name of YOUR star with the U.S. Patent Office”. No company owns the right to name stars after people. Besides, the stars those companies “name” are so dim you can’t find them. In this column, I’ll pick a constellation and representative star for each of the four colleges at CWU. Then, I’ll briefly tell the story of the constellation and relate that story to the aspect of public service CWU graduates from that college are uniquely qualified to engage in based on my version of sky interpretation. If different couples can have “their” song, then your favorite college graduate can have her or his star

Today: College of Arts and Humanities: You are the people who interpret the world in unique ways. Then, you share those ways with others. According to Greek mythology, Orpheus charmed everyone he met when he played the lyre or harp. After his wife died tragically, he journeyed to the underworld to charm its inhabitants in an effort to win his wife back to the living world. Your service reminder: use your talent to bring joy to others. The constellation Lyra and its bright star Vega should remind you of the power of the arts. Vega is five and a half fists held upright and at arm’s length above the east horizon at 11 p.m.

Sunday: Jupiter will be in opposition tomorrow night. That doesn’t mean that Jupiter refuses to listen. Opposition means that Jupiter 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. Jupiter is about two fists above due south at 1 a.m. It is about one fist above the southeast horizon at 10 p.m. Read more about Jupiter’s oppositional behavior at https://www.skyandtelescope.com/observing/jupiter-is-outstanding-at-opposition/.

Monday: College of Business. You are the future movers and shakers. The future CEOs. The future big donors to Central. Auriga represented a king of Athens who happened to be mobility impaired. Instead of sitting around waiting for others to transport him, he took the initiative to invent the four-wheeled chariot. He solved a problem for a special need. Your service reminder: address the problems of those in the most need. To remind you of that, look to the constellation Auriga. Its bright star Capella is about a half a fist above the north-northwest horizon at 11 p.m.

Tuesday: College of Education and Professional Studies. You are the teachers. The craftspeople. The technical experts. Bootes, the herdsman, was such a person. Bootes’ job was to guide the northern constellations to the feeding place and the watering hole. He and his dogs were especially in charge of Ursa Major and Ursa Minor, the greater and lesser bears. Your service reminder: guide others to a better place in life. Look to the constellation Bootes and its bright star Arcturus to remind you of this. Arcturus is five and a half fists above the southwest horizon at 11 p.m.

Wednesday: Mercury and Mars are right next to each other in the evening twilight sky for the rest of the week. Mercury is about four times brighter than Mars. They are about a fist above the west-northwest horizon at 9:30.

Thursday: College of the Sciences. You are the people who will systematically study how the world works. Agriculture is an important scientific application. Each year, farmers must use the findings of science to be successful. Who better to represent the College of the Sciences than Virgo, the goddess of the harvest? Virgo looms large in the sky holding an ear of wheat in her hand. Your service reminder: study the practical aspects of the scientific world. The ear of wheat, and your service reminder, is represented by the bright star Spica. Spica is two and a half fists above the southwest horizon at 11 p.m. Tonight; you’ve got a warrior’s spirit, as well, because the planet Mars, which represents the Roman god of war, is one fist to the right of Spica.

Friday: "Do I have to wake up yet? It's so early!" This next week gives us the earliest sunrises for the northern part of the United States, including Ellensburg.  "Wait, I thought this happened on the longest day of the year, which hasn't occurred yet." Because the Earth's orbit is not a perfect circle, the sunrise and sunset time is not symmetric so the earliest sunrise occurs before the longest day and the latest sunset occurs after the longest day. Go to http://earthsky.org/?p=4027 to read more about this phenomenon. While you are up, check out Saturn, nearly two fists above the south-southwest horizon at 4:30 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.

Thursday, May 30, 2019

The Ellensburg WA sky for the week of 6/1/19

Saturday:  The CWU Physics Department is hosting its monthly First Saturday planetarium show today from noon to 1 p.m. The CWU Astronomy Club will give a series of short shows about southern constellations, Mars, and the Moon. The show is free and open to all ages. There will be a show on the first Saturday of every month of the school year hosted by different CWU astronomers and astronomy educators. The CWU Lydig 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.

Sunday: Cygnus the swan flies tonight. Deneb, the brightest star in the constellation, whose name means “tail” in Arabic, is two and a half fists held upright and at arm's length above the northeast horizon at 10 p.m. Cygnus’ wings make a vertical line one half a fist to the right of Deneb. Its head, marked by the star Albireo, is two fists to the right of Deneb. While Deneb is at the tail of Cygnus, it is at the head of the line of bright stars. It is 160,000 times more luminous than the Sun making it one of the brightest stars in the galaxy. It does not dominate our night sky because it is 2,600 light years away, one of the farthest naked eye stars. If Deneb were 25 light years away, it would shine as bright as a crescent moon. Compare that to Vega, which is 25 light years away. Vega is three and a half fists above the east-northeast horizon at this time.

Monday: Jupiter is one fist above the southeast horizon at 11 p.m.

Tuesday: The month of June is named after Juno, the queen of the Roman gods and the mythological protector of the Roman state. In ancient Rome, the month began when the crescent moon was first seen in the evening sky from Capitoline Hill in Rome. If we still started months this way, June would start on a different day each year. This year, the new Moon is June 3 so the first day of the month would be today when the crescent moon is about 4% illuminated. Look for it a half a fist above the west-northwest horizon at 9:30 p.m. The planet Mercury is less than a fist to the right of the Moon.

Wednesday: Looking for a wet and wild vacation spot? So is NASA. That is why they are going to land the the Mars 2020 rover in Jezero Crater, which many astronomers think held an ancient lake. They hope the rover will find minerals that form in the presence of water and maybe even fossilized signs of life. For more information about the landing site, go to https://tinyurl.com/yxt6f39b. Tonight, Mars is about a fist to the lower right of the Moon at 10 p.m.

Thursday: The bright bluish star Spica is three fists above due south at 9:30 p.m.

Friday: As the weather warms up, people start thinking about swimming in a nice cool body of water. Recently, astronomers have discovered evidence an ocean about 20 miles beneath the surface of Saturn’s moon Enceladus. NASA’s Cassini probes measured variations in how the moon’s gravity pulled on the orbiting spacecraft. These variations can be explained by a large amount of liquid water under one section of the ice because liquid water is denser than an equal volume of ice. While you need a very large telescope to see Enceladus, Saturn is about a half a fist above the southeast horizon at midnight.


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.