Keep Your Eyes to the Skytesttest
A gibbous moon waxes through afternoon and evening skies this week. Friday the moon, just past first quarter, is low in the southwest after sunset, with fiery Antares, the heart of Scorpius, trailing less than 10 degrees behind.
Unlike many constellations, Scorpius actually looks like its namesake. Look between the moon and Antares for the nearly aligned stars of the scorpion’s head, while its long curving tail stretches behind to the southeast, spiking upward with several bright stars marking its stinger. Originally the scorpion had two outstretched pinchers, but Julius Caesar cut them free to form the constellation Libra. Saturday the moon is just a few degrees to the east of Antares.
The wee hours over the weekend mark the peak of the annual Southern Delta-Aquarid meteor shower. The best showings typically come between midnight and dawn, but this year the moon doesn’t set until around 3am, narrowing the window between then and dawn. The Delta Aquarids generate up to 15 to 20 meteors over the course of an hour, but some leave a glowing train that can last several seconds.
The meteors can appear anywhere in the sky, but they seem to emanate from the constellation Aquarius. However, they are much closer, part of our own solar system, the spawn of Comet 96P/Machholz, which orbits our own sun. In its travels, the comet sheds material, leaving behind a trail of ice, dust and debris, which the earth passes through this time each year. The bits of flotsam that strike against our atmosphere ignite and streak through the skies as meteors.
While this meteor shower doesn’t produce the numbers that some do, it makes up for that in longevity, with errant meteors into mid-August, just as the Northern Delta Aquarids, the sister meteor shower, brighten our night skies