Saturn rises in Aquarius shortly after 5 A.M. local time on April 1, just as twilight begins. It’s a short observation window as the Saturn season opens, but by April 30, things have improved, with Saturn rising two hours earlier and reaching 8° high at the first onset of twilight. It glows at magnitude 0.9, outshining all the stars in this region of sky. A waning crescent Moon hangs 5° below the ringed planet on April 16.
Eager observers swinging a telescope to Saturn low in the sky will be pleasantly rewarded by its 16″-wide disk and a thin set of rings, now inclined by only 9° to our line of sight. They will narrow another couple of degrees as it heads toward an August opposition. In the meantime, enjoy the reappearance of the gas giant in our skies, along with its collection of moons. Titan will be easy to spot late this month, shining at 8th magnitude and due west of Saturn on April 30.
Neptune is just reappearing from behind the Sun in morning twilight. Its magnitude 7.8 disk is poorly placed for observation in Pisces, particularly early in the month. By April 30, it is just 7° high an hour before sunrise.
Jupiter is in conjunction with the Sun April 11 and not visible this month.
This month’s April 20 solar eclipse is an unusual “hybrid” eclipse. The eclipse begins and ends as an annular eclipse, but for most of its path, it is total. This occurs because the curvature of Earth causes the Moon’s shadow to fall short of reaching the surface for the east and west extremities of the track, where our planet’s surface curves away. But the eclipse is total along the central part of the track. Hybrid eclipses are rare, with just five to 24 per century.
April’s solar eclipse begins as an annular eclipse at sunrise over the waters of the south Indian Ocean and makes landfall on a tiny promontory of the Cape Range National Park, located 800 miles north of Perth, Australia. Totality lasts some 62 seconds at this remote location.
The moment of greatest eclipse, where totality lasts 1 minute 16 seconds, lies just off the coast of Timor. The track reaches tropical West Papua in the early afternoon, where mountains rise to nearly 10,000 feet and generate lots of weather. The eclipse track briefly visits the island of Biak (65 seconds of totality), which has some developing tourist centers and is the location of a major battle of World War II. The track then races across the Pacific Ocean, turning into an annular eclipse again near sunset, just south of the Marshall Islands.
The next solar eclipse is an annular eclipse on Oct. 14 across the western U.S. and northern South America. It will serve as a preview for the April 8, 2024, total solar eclipse that will cross parts of Mexico, the U.S., and Canada.
