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The Sky This Week, 2020 April 14 - 21

The Lion in the Sky
Constellation Leo, imaged 2020 January 1 from Mollusk, Virginia.
Constellation Leo, imaged 2020 January 1 from Mollusk, Virginia
with a Canon EOS Rebel SL2 DSLR and 24mm EFS lens mounted on an Omegon Mini Track LX2
mechanical star tracker

The Moon moves may be found in the pre-dawn sky this week working her way into the rising stars of the autumnal sky.  She begins the week by passing three degrees south of Saturn on the morning of the 15th.  On the following morning she may be found at a similar distance southeast of ruddy Mars.  New Moon occurs on the 22nd at 10:36 pm Eastern Daylight Time

This week’s highlight is the April observing campaign for the Globe at Night citizen-science program dedicated to bringing awareness to the night sky to people all over the world.  All that you need are your eyes and a clear view of the sky that includes the constellation of Leo, the Lion.  This heavenly beast can be found crossing the meridian high in the south between 9:30 and 11:00 pm local time.  Leo’s brightest star, Regulus, sits at the bottom of an asterism known as The Sickle, which outlines the lion’s head and mane.  His haunches are delineated by a right triangle of second- and third-magnitude stars that follow to the east of the sickle.  Together they make a fairly good depiction of a crouching lion and remind me of an Egyptian sphinx.  Once you find Leo, compare the view you have with the magnitude charts on the Globe at Night web app to determine the quality of your local sky.  Your information will help scientists monitor the spread of artificial light pollution that is gradually robbing us of our view into deep space.

The stars that make up Leo have represented a lion to many cultures dating back over 4000 years in time.  In Greek mythology the constellation symbolizes the Nemean Lion, a fearsome creature whose hide could not be penetrated by any kind of weapon.  Leo was eventually done in by the strongman Heracles (Hercules to the Romans), who grappled with the lion in close quarters in the first of his Twelve Labors.  Using just his great strength and bare hands, he succeeded in grabbing the lion’s legs and then breaking its back, taking its hide as a prize.  

Overlapping with the Globe at Night campaign is International Dark Sky Week, which begins on the 19th.  Normally this is a time to participate in programs sponsored by local astronomy clubs, planetariums, and observatories to bring public awareness to the wonders of the night sky, but this year it is being celebrated “virtually”.  Throughout the week the International Dark Sky Association will be sponsoring webcasts and other events to pique your interest and help you learn to enjoy the many splendors of the night sky.  I think of the sky as the “world’s largest national park”, free and open to anyone with curiosity and a desire to learn our place in the Universe.  This week is a great week to kindle that interest.

Venus continues to blaze away in the western sky during evening twilight and the first hours of darkness.  She is now reaching her brightest magnitude for this apparition, outshone only by the Moon in the nighttime sky.  If you are fortunate to live in a very dark locale this would be the perfect week to go out and look for your shadow cast by Venus’ glow.  During the course of the week she drifts eastward through the stars of Taurus, the Bull, passing well north of Aldebaran, the Bull’s brightest star.

Early in the week it’s worth getting up before sunrise to watch the waning Moon cavort among the planets Jupiter, Saturn, and Mars.  Luna hangs with them on the 15th and 16th, then moves off to the star-poor autumnal constellations.  The brightest of the planetary trio is Jupiter, which you will find to the east of the “Teapot” asterism that makes up part of the summer constellation of Sagittarius, the Archer.  Despite his low declination, Jupiter is always worth a glance through the telescope, towing his four Galilean moons along as he slowly drifts eastward toward Saturn.  Ruddy Mars lies east of the pair of giant planets, his ruddy hue quite distinctive against the dim stars of Capricornus.  Mars is now gradually brightening as Earth begins to catch up to him, so he’s now on par with the pale-yellow glow of Saturn.

 
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