Here we are already in October, the first full month of fall. Days are really getting shorter now. Do you sometimes think they are getting shorter at a faster rate? If you have, or have heard others saying something like, “Boy, it is really getting dark early,” you are not imagining things. The length of day changes the greatest around the equinoxes (first days of fall and spring) and the least at the solstices (start of winter and summer). According to my computer program, day length in October decreases by about an average of three minutes a day. In December, by contrast, we only lose about 1/3 of a minute a day. Don’t despair if you miss the Sun, the opposite happens in Spring, when the length of day increases at a more rapid rate.
If you like the full Moon, you have two of them in October. The Moon will be full at the start of the month on Oct. 1, the “Harvest Moon,” and also on Halloween, the “Hunters Moon.” With good weather, we’ll have some nice moonlight to guide the way for young trick-or-treaters. New Moon will occur on October 16.
Jupiter and Saturn will still be nicely visible in the evening sky, but the real story of October will be Mars. The red planet makes its closest approach to Earth about every two years, and that will happen this month, on the 13th. Mars will be about 35.8 million miles from Earth at that time. It will be unmistakable in the southern sky, with its distinct reddish color, and its brightness—it will outshine stars in the southern sky and will be brighter than Jupiter and Saturn. Get a look in mid-October if you can, since Mars will move away from us quite quickly. By the end of October, it will be over 43 million miles from us, 60 million miles distant by Dec. 1, and about 84 million miles away by the first of the year. Look for Mars in the southeastern evening sky. One good time will be Oct. 2; Mars will be right above the waning gibbous Moon. Don’t miss Mars in October!
With sunrise coming later in the morning, many folks arise when skies are still dark. Take a peek at the eastern sky with your morning cup of coffee and enjoy dazzling Venus, low in the morning sky. On the mornings of Oct. 2 and 3, Venus makes a close approach with the bright star Regulus in the constellation Leo. Venus has enjoyed some recognition lately, with the discovery of the chemical phosphine in its atmosphere. Phosphine here on Earth is known to be made by microbes that thrive in oxygen-free environments and is made industrially. The possible link with microbial life makes the Venus discovery of great interest. There may be a yet-to-be discovered way it is formed chemically. Safe to say that we will see future exploration of Venus’ atmosphere!
If you have binoculars, try locating the “Double-Cluster” in the constellation Perseus, in October’s northeastern sky. Two neighboring clusters of stars, about 7,400 light-years distant, make for a very nice sight. They are faintly visible with the naked eye. Look in the northeast and find the “W” shaped constellation Cassiopeia. Directly below Cassiopeia is the constellation Perseus. The clusters are about 15 degrees below Cassiopeia, or a bit larger than the width of your fist with your arm outstretched. Use the picture with this article to help locate it.
Many readers are familiar with the Goldendale Observatory State Park and may be wondering what is up with the facility with the COVID-19 pandemic. COVID’s timing could not have been worse; the upgraded facility had just re-opened last winter when the pandemic hit us, and the Observatory is still closed. You can, however, enjoy presentations from Observatory Director Troy Carpenter online, via Facebook. Troy has put together three presentations to date, one discussing Venus and its phases, one focusing on comet Neowise, and a more recent one, “virtual astronomy.” To view the videos, go the Goldendale Observatory web page (www.goldendaleobservatory.com), click on “Special Events”, and then on “Facebook: WA State Parks.” That will take you to the Washington State Parks Facebook page (you need to be logged in to Facebook). On that page, click on “videos” and scroll down to find the Observatory videos. You’ll be treated to some excellent information and great astrophotography. A perfect activity for a cloudy evening!