Saturday: Listen; do you want to know a secret? Do you promise not to tell? Whoa oh, oh. The Beatles certainly didn’t write this song about the Barringer meteorite crater in Arizona. Astronomers are studying this 50,000-year-old impact to learn more about our planet’s violent history as well as the physics of impacts throughout the solar system. If you’d like to be let in on some of these secrets, go to http://goo.gl/sqbBe.
Sunday: At 7 a.m., Jupiter is two and a half fists above the south horizon, a little bit west of due south. Mars is a little more than a fist to the lower left of Jupiter. Saturn is one fist above the southeast horizon.
Monday: There are about 6,000 stars visible to the naked eye. Soon there may be one more: The Humanity Star. This is not a nova or supernova. It is a highly reflective 65-panel geodesic sphere that was conceived by Peter Beck and launched by his private space launch company called Rocket Lab. The Humanity Star orbits the Earth once every 90 minutes. You can track its motion and read more about it at https://www.thehumanitystar.com/.
Tuesday: At 10:30 p.m., the blue giant star called Adhara is one and a half fists above due south. It is one of the brightest stars in the sky. Currently over 430 light years away, Adhara was only 34 light years away five million years ago. That proximity made it the brightest star in the nighttime sky at the time.
Wednesday: Full Moon. Super Moon. Blue Moon. Blood Moon. These sound like possible names for the children of The Who’s original drummer. In actuality, these describe the Moon this morning. Let’s take these names from least to most exciting. Tonight’s Moon is full. It is the second Full Moon of the month which makes it a Blue Moon. The Moon is Super because it is at its closest point to the Earth during the time that it is full. That means the sunlight is reflecting off of an object that appears about 30% larger than when the Moon is farthest from the Earth.
But most exciting of all, there is a total lunar eclipse this morning. Total lunar eclipses are not as noticeable as total solar eclipses because light still reaches the Moon even when it is completely blocked by the Earth. That is because the Earth’s atmosphere acts like a lens and bends rays of light toward the Moon that would normally miss the Moon. That doesn’t mean the Moon looks the same during a total lunar eclipse as it does during a normal full moon.
Sunlight is white. White light is the sum of all of the colors in the visible spectrum (red, orange, yellow, green, blue, indigo and violet). Our atmosphere scatters the blue component of the Sun’s white light. That is why our sky is blue. (If our atmosphere consisted of different gasses, we would likely have a different colored sky.) When the Sun or Moon is near the horizon, the light passes through a lot of the atmosphere meaning a lot of the blue light is scattered and the Sun or Moon looks redder than when it is high in the sky. During a total lunar eclipse, sunlight passes through a large slice of the Earth’s atmosphere. The remaining light that reaches the Moon is reddish. Some people say the fully eclipsed Moon looks Blood Red! These people exaggerate. It arrears a dull reddish color.
From our perspective in central Washington, the partial eclipse stage will start at 3:49 a.m. The Moon will slowly move into the Earth’s shadow and get dark from left to right. At 4:42 a.m., the Moon will be fully eclipsed. The total eclipse lasts until 6:08 a.m. The moon will be moving out of the earth’s darkest shadow or umbra until 7:11 a.m. After that, the moon will look white, just like a normal full moon. Thus, during the entire eclipse, the moon looks white, then black, then red all over. For more information about the eclipse, including information about the specific times for your location, go to https://www.timeanddate.com/eclipse/lunar/2018-january-31.
Thursday: Today is Groundhog Day. If Punxsutawney Phil doesn’t see his shadow this 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 good news is the days are getting longer and the nights are getting shorter. The better news for most readers of this column is the farther north you go in the United States, the longer the days get. Here in Ellensburg, there is now one and a half more hours of daylight than on the first day of winter. In the southern part of the US, there is only 35 more minutes of sunlight. If you’d like to have your own fun with day lengths and other time questions, go to https://www.timeanddate.com/sun/.
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.
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