This week – during the dark hours before dawn on or near July 28, 2017 – the Delta Aquarid meteor shower should reach its peak. The Delta Aquarids are a long, rambling shower, which will stretch out for weeks beyond the peak. The peak itself isn’t very definite, but – if you want to watch around the peak – now is the time. With no moon to ruin the show in the best hours to watch – before dawn as seen from around the world – this week is a good time to watch for these rather faint meteors, which might number about 10 to 15 meteors per hour in a dark sky.
The most favorable viewing window begins about 1 a.m. (2 a.m. Daylight Saving Time) no matter where you are on Earth … through the onset of morning dawn. Although this shower is visible from both the Northern and Southern Hemispheres, it tends to favor the more southerly latitudes. North of the equator, it’s better seen in the tropical and subtropical regions rather than farther north. This shower will combine with the more-famous Perseid meteor shower, now rising to its peak, but whose peak in 2017 will be drowned in bright moonlight.
That’s why now is the time to watch meteors.
The Perseid meteor shower’s annual peak is around August 12 or 13. In 2017, the waning gibbous moon will interfere.
This week, a waxing crescent moon sets at early evening, providing for dark skies for the (nominal) peak nights of the Delta Aquarid shower. Once again, the best viewing window is during the wee hours before dawn.
The Delta Aquarid shower is, at best, a modest shower. About five to ten percent of these relatively faint, medium-speed meteors leave persistent trains – glowing ionized gas trails that last a second or two after the meteor has passed.
This shower recurs annually in late July, because the Earth crosses the orbital path of Comet 96P/Machholz at this time of year. The stream of debris left behind by this comet smashes into the Earth’s upper atmosphere, to burn up in our sky as Delta Aquarid meteors.
If you trace the paths of the Delta Aquarid meteors backward, they all appear to radiate from a certain point in the starry heavens – near the star Delta Aquarii (Skat). This point is called the radiant of the Delta Aquarid meteor shower. As a rule of thumb, the higher the radiant point is in your sky, the more meteors that you’re likely to see. In late July, this star climbs highest up in the sky at roughly 2:30 a.m. (3:30 a.m. Daylight Saving Time).
Of course, you don’t have to find the radiant point of the Delta Aquarid shower to enjoy this shower. Radiating from near the star Skat, the meteors will streak every which way across the starry heavens. Just find an open view of the sky away from artificial lights, sprawl out comfortably on a reclining lawn chair, preferably between midnight and dawn, and watch.
Bottom line: Unless you live in the far northern part of the globe – where there is little or no nighttime at this time of year – the Delta Aquarid meteor shower can be seen from all around the world. The nominal peak is around July 27 or 28, in the dark hours before dawn. But the Delta Aquarids will still be going when the Perseids peak a couple of weeks from now. At that time, a bright waning gibbous moon will interfere with the show. So start your meteor-watching now!