Wednesday, January 25, 2023

The Ellensburg, WA sky for the week of January 28, 2023

Saturday: Regulus, the brightest star in the constellation Leo the lion, is one and a half fists held upright and at arm’s length above due east at 8:00 p.m.

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 morning sky, it is west of the Sun and this occurrence is called the greatest western elongation. This morning, Mercury is a half a fist above the southeastern horizon at 7:00 a.m. Over the next few weeks, Mercury will move toward the Sun in the sky. By late March, it will be visible in the evening  sky.

Monday: Are you interested in participating in astronomy research? You don’t need to go back to school. You don’t need to spend thousands of dollars getting a fake degree from an online university. The scientists working on the High Resolution Imaging Science Experiment, or HiRISE, camera on NASA's Mars Reconnaissance Orbiter would like your input on which objects they should target for close-up pictures. While you may think the scientists are just trying to build interest in their project by having people look at pretty pictures, there is a real scientific benefit to having many eyes searching for interesting targets. There aren’t enough scientists to carefully inspect all of the low power images. And surprisingly, computers are not nearly as effective as people in making nuanced judgments of images. So, go to https://www.uahirise.org/ and click on the HiWish button. You’ll be on your way to suggesting close-up targets for NASA's Mars Reconnaissance Orbiter. If that is too much work for you, just go outside. Mars is right above the moon, within a full moon diameter, at 8:00 p.m. They’ll move through the sky together until both set at around 4:00 pm.

Tuesday: Saturn is a half a fist above the west-southwestern horizon at 5:45 p.m. Venus is much brighter than Saturn and is about a fist above the west-southwestern horizon. Jupiter is three and a half fists above the southwestern horizon.

Wednesday: Winter is a good time to see the thick band of the Milky Way galaxy. It arches high in the early evening sky at 8:00 p.m. starting in the southeast by Sirius, the brightest star in the night sky. Climbing from Sirius through the "horns" of Taurus to the bright star Capella nearly straight overhead, it drops down toward M-shaped Cassiopeia in the north and the tail of Cygnus the swan and its bright star Deneb, in the northwest.

Thursday: Today is Groundhog Day, an important day for pop culture astronomers and Bill Murray movie fans. If Punxsutawney Phil doesn’t see his shadow tomorrow morning, he is telling us that he follows the Chinese calendar and that spring starts early. On the Chinese calendar, equinoxes and solstices occur in the middle of their respective seasons. In order for the vernal equinox to occur in the middle of spring, spring must start on February 3 or 4, depending on the year. Thus, if Phil doesn’t see his shadow, legend is that spring will start on February 3 or 4 as on the Chinese calendar. If Phil sees his shadow, he is telling us he agrees with the western calendar and that there will be six more weeks of winter meaning spring will start near March 20.

Friday: The brightest star in the head of Draco the dragon is called Eltanin, based on the Arabic At-Tinnin or “great serpent”. It is currently about 150 light years away. Eltanin is moving towards our Solar System. In 1.5 million years, it will be only 28 light years away and the brightest star in the night sky, nearly as bright as Sirius is currently. Eltanin is one fist above due north 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.

Thursday, January 19, 2023

The Ellensburg, WA sky for the week of January 21, 2023

Saturday: Winter is the best season for finding bright stars. And if you only want to set aside a few minutes, 10:00 p.m. tonight just might be the best time because the winter hexagon is due south. Starting at the bottom, find Sirius, the brightest star in the night sky, two and a half fists held upright and at arm’s length above the southern horizon. Going clockwise, Procyon (8th brightest star in the night sky) is about two and a half fists to the upper left of Sirius. Pollux (17th brightest) is about two and a half fists above Procyon. Capella (6th brightest) is about two and a half fists to the upper right of Procyon and close to straight overhead. Going back to Sirius at the bottom, Rigel (7th brightest) is about two and a half fists to the upper right of Sirius. Aldebaran (14th brightest) is about three fists above Rigel. Adhara (22nd brightest) is a little more than a fist below Sirius and Castor (24th brightest) is right above Pollux. Betelgeuse (10th brightest) is in the center of the hexagon, five fists above due south. That’s nine of the 24 brightest stars visible in the night sky congregated in one small section of the sky. 

Sunday: At 5:30 p.m., Venus and Saturn are less than a half a degree apart in the sky. They are so close together that you couldn’t even squeeze the full moon between them. See Venus and Saturn one fist above the southwest horizon. For comparison, the moon is below the two planets.

Monday: You think wintertime weather is bad in Ellensburg. Astronomers have discovered storms and earth-sized clouds on a brown dwarf. These are cool, small stars that are not massive enough to fuse hydrogen atoms and fuse hydrogen. In fact, they are more similar to gas giant planets such as Jupiter than to the Sun. Luckily, astronomers are getting better at predicting this weather. That means you can plan your brown dwarf picnic and it can be more enjoyable. For more information, go to https://www.nasa.gov/feature/jpl/scientists-improve-brown-dwarf-weather-forecasts 

Tuesday: Do you ever take photos to spy on your neighbors? The Hubble Space Telescope does. In 2019, Hubble scientists released the best image of the Triangulum Galaxy, the second closest spiral galaxy to Earth. Hubble’s Advanced Camera for Surveys weaved together 54 separate images to provide enough detail to see 10 million individual stars out of the estimated 40 billion stars in the galaxy. See the pictures at https://www.spacetelescope.org/news/heic1901/. At 7:00 p.m., the Triangulum Galaxy is six and a half fists above the southwestern horizon. It is barely visible with binoculars. First find the Great Square of Pegasus, centered four fists above the western horizon. It is tripped so it appears to be balanced on a corner. Go to the top star in the tilted square. Move your binoculars about one binocular field of view, about a half a fist above the corner star. You’ll see a pair of stars of similar brightness in that field of view. Then move your binoculars up another field of view to two stars that are a little brighter and a little farther apart than the previous pair. The brighter of the two is named Mirach. About one binocular field of view, or about a half a fist to the right of Mirach is the largest galaxy in our neighborhood and the brightest in the sky: the Andromeda Galaxy. About one binocular field of view, or about a half a fist to the left of Mirach is the Triangulum Galaxy, also known as Messier 33 (M 33). The Triangulum is much more challenging to see.

Wednesday: Draco Malfoy makes an appearance in all seven books of the Harry Potter series. Perhaps you’ve heard of these. But the constellation Draco the dragon makes an appearance in the sky every night. It is a circumpolar constellation as viewed from Ellensburg meaning it never goes below the horizon. The head of the dragon is one fist above due north at 9:30 p.m. Eltanin, the brightest star in the constellation, is at the lower left-hand corner of the trapezoid-shaped head of Draco.

Thursday: Mars is nearly seven fists above due south at 8:00 p.m.

Friday: Mercury is a half a fist above the southeastern horizon at 7:00 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, January 12, 2023

The Ellensburg, WA sky for the week of January 14, 2023

Saturday: Most constellations don’t look like the object their name refers to. That’s because most constellations don’t have such a simple object to emulate as Triangulum does. Triangulum is shaped like a… wait for it…. wait for it…. A thin isosceles triangle. Metallah is the only mononymous star in the constellation. In Latin this star is called Caput Trianguli, the head of the triangle. Triangulum is four and a half fists held upright and at arm’s length above due west at 9:30 p.m. The triangle is pointing straight down with Metallah. The Triangulum Galaxy can be seen with binoculars about half a fist to the lower right of Metallah. This is the galaxy that the USS Enterprise travels to after the warp drive engine malfunctions in The Next Generation episode called “Where No One Has Gone Before”.

Sunday: This weekend, Mars is as far north in the sky compared to the background star as it is going to get this year. Thus it is a great night to observe without being distracted by the city lights. Mars is nearly seven fists about due south at 8:30 p.m. At this same time, Jupiter is two fists above the west-southwest horizon.

Monday: Have you ever looked down on the ground and spotted a penny? In Yakima? While you were standing in Ellensburg? If you have, then you may be able to see the star Hamal as more than just a point of light. It has an angular diameter that can be directly measured from Earth. Hamal, the brightest star in the constellation Aries the ram, has the same angular diameter as a penny 37 miles away. (For comparison, the moon is about half the diameter of a penny held at arm’s length.) Hamal is about four and a half fists above the western horizon at 9:30 p.m. Hamal is just to the left of Triangulum and is the brightest star in that region of the sky.

Tuesday: Bright Venus is nearly a fist above the southwestern horizon at 5:30 p.m. The much dimmer Saturn is about a half a fist to the upper left of Venus.

Wednesday: Antares is less than a half a fist to the right of the moon at 6:00 am. They are low in the southeastern sky.

Thursday: You never see a giraffe on the ground in Ellensburg. But you can look for one every night in the sky. The constellation Camelopardalis the giraffe is circumpolar from Ellensburg’s latitude of 47 degrees north meaning it is always above the horizon. Don’t expect to be overwhelmed by the appearance of the stars in Camelopardalis. The brightest star in the constellation appears only about half as bright as the dimmest star in the Big Dipper. However, the actual luminosities of the three brightest stars in Camelopardalis are very high, each at least 3,000 times more luminous than the Sun. Alpha Camelopardalis, a mind boggling 600,000 times more luminous than the Sun, is seven fists above due north at 9:00 p.m.

Friday: This next week is, on average, the coldest of the year so it is time to turn up the furnace. Fornax the furnace is one fist above due south at 7:00 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.