Max Morning Mercury, Mars, Moon and M45, Jupiter Season Starts, and See Peak Pallas!
The Moon and Planets
This is the perfect week in April to view our natural satellite in all of its splendor. After last Friday’s New Moon phase, the young crescent moon will be waxing fuller and climbing the western sky after sunset. Tonight (Sunday) and tomorrow, look for Earthshine to brighten the unlit portion of the moon. Earthshine is sunlight that has been reflected off the Earth and back onto the near side of the moon. My mother used to call it “the Old Moon in the New Moon’s Arms”.
As the moon waxes fuller every evening, the sun is rising over the lunar surface. All along the terminator, the pole-to-pole boundary that separates the lit and darkened hemispheres, sunlight is striking the moon at a very shallow angle — casting long, deep, black shadows from every elevated part of the lunar terrain. That includes crater rims and central peaks, mountain chains, faults, and even lava flows. The sights change hour by hour and night by night as the sun rises, and are perfect for viewing in binoculars and backyard telescopes — all at a convenient time of the evening!
Monday evening will also see the moon land about a palm’s width below reddish Mars and the bluish stars of the Pleiades Cluster. That cluster, named Subaru in Japan, also serves as the logo for the well-known car maker. On Tuesday night, the moon will hop to sit to the upper left of Mars, between the horns of Taurus (the Bull). On either night, look for the very bright reddish star Aldebaran (the Bull’s eye) sitting a generous palm’s width to the left of Mars.
On Wednesday evening, the moon’s generous crescent will sit near the stars that mark the upraised club of Orion (the Hunter). The following evening will place the moon between the twins of Gemini. Look for the stars Mekbuda and Mebsuta, each sitting about three finger widths above and to either side of the moon. Those stars mark the hips of Pollux and Castor, respectively.
The moon will reach its First quarter phase, in daylight, on Friday afternoon. At that time, the angle between the sun, you, and the moon will form a 90° angle. (Point at the sun and the moon at the same time, and note the angle between your outstretched arms.)
In the southwestern sky after dusk on Saturday, the waxing gibbous moon will be positioned a few finger widths to the upper left (east) of the large open star cluster in Cancer (the Crab) known as the Beehive, Praesepe, and Messier 44. Binoculars will encompass both the moon and the cluster in the same field of view, but to see the clusters’ stars, position the moon just outside of your binoculars’ field of view. A few hours earlier, at approximately 19:30 GMT, observers in Western Europe, the Middle East, and eastern Africa can see the moon pass directly through the cluster.
On Sunday night, the moon will sit less than a palm’s width to the right of the bright, white star Regulus. See if you can find the backwards question mark of stars extending upwards from Regulus. Those five stars form the front end of Leo (the Lion). The shape measures about 1.5 fist diameters, top to bottom.
As I mentioned above, the planet Mars will continue to be easily visible every evening this week, but only for a couple of hours after dusk. Mars will set in the west at about 10:45 pm local time. Once the sky has darkened, look for Mars as a medium-bright, reddish pinpoint of light sitting one-third of the way up the western sky. Mars has been slowly shrinking in size and brightness as we increase our distance from it little-by-little. Mars has been sliding a bit farther from the Pleiades cluster every night.
Hooray! For the first time in months, Jupiter will officially enter the evening sky this week. Tonight, the king of planets will be rising just after midnight. But the motion of the Earth around the sun causes celestial objects to rise four minutes earlier every night, so Jupiter will be available for evening star parties in time for the warm weather. By 5 am, Jupiter should still be visible in the sky over the southern horizon.
Yellowish Saturn will rise after 1:30 am local time this week — but, being dimmer than Jupiter, it will become lost in the southeastern twilight before 5 am. Look for Saturn sitting approximately 2.5 fist diameters to the left of Jupiter.
Mercury and Venus are both low in the eastern sky just before sunrise this week. For some time now, very bright Venus has been descending and moving eastward toward Mercury (and the sun). Speaking of which, look for the elusive innermost planet sitting only about a palm’s width to the lower left of Venus. On Thursday morning, Mercury will reach its widest separation 28° west of the Sun. Due to Mercury’s position well below a slanted morning ecliptic, this will be a very poor pre-dawn appearance for Northern Hemisphere skywatchers, but a very good one for those viewing Mercury from the Southern Hemisphere.
If you’ve ever wanted to see an asteroid, this week offers a fantastic opportunity. On Wednesday, the main belt asteroid designated (2) Pallas (i.e., the second asteroid discovered, in 1802) will reach opposition, its closest approach to Earth for this year. On the nights around opposition, Pallas will shine with a peak visual magnitude of 7.9, well within reach of binoculars. As a bonus, the asteroid will be situated only a quarter of a finger’s width to the left (east) of the bright double star named Murphrid in Boötis (the Herdsman). That star is also designated Eta Boötis (η Boötis). (Murphrid is always situated about a slim palm’s width to the right of the very bright star Arcturus.)
Pallas and the star will easily fit within the field of view of a backyard telescope. The duo will already be climbing the eastern sky after dusk and will spend the night crossing the sky together. Asteroids move so fast that you should see Pallas’ distance from Murphrid vary in as little as half an hour!
Astronomy Skylights for the week of April 7th, 2019 by Chris Vaughan.
Keep looking up, and enjoy the sky when you do. I love questions and requests — so, send me some!
