Jupiter at peak visibility, Sirius at magnitude -1.5, and other cool things to look for in the sky this week.
By Nicole Kiefert
Monday, April 10
Full Moon arrives at 2:08 a.m. EDT tomorrow morning (11:08 p.m. PDT this evening), but our satellite looks completely illuminated all night. It rises in the east shortly before the Sun sets and reaches its peak in the south around 1 a.m. local daylight time. The Full Moon lies in central Virgo, some 3° from brilliant Jupiter and 7° from that constellation’s brightest star, 1st-magnitude Spica.
Tuesday, April 11
After passing between the Sun and Earth only two weeks ago, Venus already appears conspicuous in the predawn sky. It rises more than an hour before the Sun and climbs nearly 10° above the eastern horizon some 30 minutes before sunrise. The planet shines so brightly, at magnitude –4.6, that it shows up easily in the brightening twilight. A telescope will deliver spectacular views of the inner world’s 52″-diameter disk, which appears just 10 percent lit.
Wednesday, April 12
Mars continues to put on a nice show these April evenings. It appears nearly 20° high in the west an hour after sunset and doesn’t dip below the horizon until after 10 p.m. local daylight time. The magnitude 1.5 Red Planet crosses from Aries the Ram into Taurus the Bull today. Unfortunately, Mars’ 4″-diameter disk shows no detail when viewed through a telescope.
Thursday, April 13
For those who like to observe during the quiet predawn hours, Saturn offers a visual treat. The ringed planet rises shortly before 1 a.m. local daylight time and climbs about 30° high in the south by the time morning twilight begins. It shines at magnitude 0.3 against the backdrop of northwestern Sagittarius, where it appears nearly stationary relative to the background stars. Take a look at Saturn through binoculars and you’ll also see the open star clusters M21 and M23 as well as the spectacular Lagoon (M8) and Trifid (M20 ) nebulae less than 4° to its east. When viewed through a telescope, the planet shows a 17″-diameter disk surrounded by a stunning ring system that spans 39″ and tilts 26° to our line of sight.
Friday, April 14
Orion the Hunter stands out in the western sky as darkness falls this week. The conspicuous constellation appears slightly askew compared with its appearance in winter’s evening sky. Now, the three-star belt is aligned parallel to the horizon while blue-white Rigel hangs directly below the belt and ruddy Betelgeuse stands directly above.
Uranus is in conjunction with the Sun at 2 a.m. EDT. From our earthly perspective, this means the distant planet lies behind the Sun and so is out of sight. Uranus will return to view in the morning sky in late May.
Saturday, April 15
The Moon reaches apogee, the farthest point in its orbit around Earth, at 6:05 a.m. EDT. It then lies 251,950 miles (405,475 kilometers) from Earth’s center.
Sunday, April 16
The annual Lyrid meteor shower begins today. Although the shower won’t peak until the morning of April 22, you may see a few meteors in the predawn hours before then. To tell a Lyrid from a sporadic meteor, trace the streak of light back to its origin. Lyrids appear to come from the constellation Lyra the Harp, while sporadics appear at random and can come from any direction.
The waning gibbous Moon appears just above Saturn before dawn. The two approach each other as the morning progresses, and the Moon will pass 3° north of the planet at 2 p.m. EDT.