THE SOUTHWORTH PLANETARIUM 70 Falmouth Street Portland, Maine 04103 (207) 780-4249 usm.maine.edu/planet 43.6667° N 70.2667° W Altitude: 10 feet below sea level Founded January 1970 2021-2022: CIII "Ok, one last FACT or FOOL: One can walk between Norway and North Korea while only having to pass through one country." (Answer at the end of the article.) THE DAILY ASTRONOMER Monday, April 4, 2022 April 2022 Night Sky Calendar Part I April is the cruelest month, you say! Forsooth! (True, we have no idea what 'forsooth' means, but, heavens that word certainly adds some literary oomph to even the silliest articles.) How could one call the fourth month anything but sublimely lovely and as full of hope and potential as a berry is gravid with nectar and nourishment. We're wicking away the last vestiges of winter (i.e. sub-freezing nights, assailing gusts, and slowly melting plow mounds that resemble charcoal-coated mountain ranges) and moving inexorably into mid-spring warm's embrace. While the winter constellations Taurus, Orion and Canis Major descend in the west, the summer stars, such as those comprising the Summer Triangle, are slowly ascending in the evening. The same celestial cycles that have shifted the seasonal constellations from center stage to the western exit continue to churn with comforting predictability. Part one of our night sky calendar begins with a new moon, which, we know, has already passed! *FRIDAY, APRIL 1: NEW MOON* How appropriate to begin the month with a new moon. Now, the lunar cycle's progression will directly follow that of the month. We shouldn't forget that the word "month" is based on "moonth," in reference to the duration of one moon cycle. Lunation cycle 1228 begins. Since the new moon occurs on the first day of April, we'll experience another new moon this month. Whereas the second full moon in one month is known as a "blue moon," the second new moon in one month is called a "black moon." *SATURDAY, APRIL 2: MERCURY AT SUPERIOR CONJUNCTION* Have you noticed that Mercury seems to pass into conjunction quite often? First, Mercury can pass into either *inferior conjunction*, when it passes between the Sun and Earth and *superior conjunction,* when it passes to the far side of the Sun relative to Earth. All the other planets, except Venus, can only pass into superior conjunction. Also, Mercury completes an orbit once every 88 Earth days! However, because Earth moves as well, the time period between successive superior conjunctions - or successive inferior conjunctions- equals about 116 days. Divide that value, known as Mercury's *synodic period,* by two and Mercury will move into conjunction every 58 days approximately. The remaining Mercurian conjunctions in 2022 are as follows: - May 21 Inferior conjunction - July 16 Superior conjunction - Sept 23 Inferior conjunction - Nov 8 Superior conjunction *TUESDAY, APRIL 5: MARS 0.3 DEGREES SE OF SATURN (Bronze event!)* Both Mars and Saturn rise just before 3 a.m. in the eastern sky! Although they are almost equally bright (Mars magnitude: 1.0; Saturn magnitude: 0.9), one can distinguish between these two worlds by their colors. While Saturn appears yellowish, Mars exudes a distinctive reddish hue due to the iron oxide in its soil. This morning, telescope viewers can observe them both simultaneously. Those who observe them with just the unaided eye will see them appearing to draw close to one another. Naturally, this apparent proximity is illusory. Mars is currently 166 million miles from Earth; Saturn's distance from Earth will equal 975 million miles today. The night sky never reveals depth. *THURSDAY, APRIL 7: MOON AT APOGEE* The moon reaches the farthest point from Earth in this orbit. Our natural satellite will stray 404,438 kilometers from Earth on this date. *SATURDAY, APRIL 9: FIRST QUARTER MOON* A full moon that occurs when the moon is at or near perigee is called a *super moon*. A full moon which happens around the time of apogee is known as a *micro moon*. A first quarter moon that directly follows or immediately precedes apogee is called, well, a first quarter moon that directly follows or immediately precedes apogee. We haven't yet coined a term for this type of moon. Perhaps we could call a first quarter moon occuring near apogee a *nickel* moon, as it is smaller than a usual quarter. Or, perhaps we could just leave it be and focus on something important. *TUESDAY, APRIL 12: JUPITER 0.1 DEGREES NNW OF NEPTUNE* No, Neptune isn't visible....even to those eagle-eyed astronomical types who assert that, given a dark clear sky and ample adaptation time, they could spy churning granules on Sirius B, which, incidentally, doesn't have any. Neptune lies hidden to those who scan the firmament with unaided eyes. However, tonight, Jupiter, which, at magnitude -2.1 is bright enough to pass Calculus tests without any preparation, will appear to veer close to the eighth world. Mind you, Jupiter is 2.3 billion miles closer to us than Neptune and so appears 10.469 times brighter! *SATURDAY, APRIL 16: FULL MOON!* The Pink Moon rises. No, that is not just another color name like blue moon or black moon. That is the term often applied to the first full moon in spring. Why? Well, perhaps it is in reference to the vibrant buds and flowers that are are dabbling the landscape or, perhaps, to the color of our appendages which are finally starting to receive blood flow after four months of the life-imperiling cold that caused the majority of our blood supply to migrate toward our vital organs. The land is thawing out, and so are we. Hence, the ascent of the pink moon! PART II tomorrow. ONE LAST FACT OR FOOL: *One can walk between Norway and North Korea while only having to pass through one country.* FACT! Yes, one can walk from Norway to North Korea while only having to pass through Russia. Mind you, it would be a darn long walk and you might want to go in the opposite direction. To subscribe or unsubscribe from the Daily Astronomer: https://lists.maine.edu/cgi-bin/wa?SUBED1=DAILY-ASTRONOMER&A=1