Sky-Watcher Alert: Meteor Show Peaks This Week

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Moonlight can cut observers' hourly rates by a half, three-quarters, or more if the nearly full moon is in the sky and shining directly in their eyes. Therefore, night owls who stay up to the wee hours of the morning will have the best chances of seeing any shooting stars, Gramer said.

For observers who cannot wait for the moon to set, Gramer said they can still catch sight of a shooting star. They'll have to find a spot where their view of the sky is unobstructed but the moon is blocked out by trees or a building.

Bone describes the moonlight interference as "frankly awful" but said the upside is a dark sky for the Perseids, which he expects to be excellent this year. Peak rates for the Perseids may reach outbursts at ten times the rate of the South Delta Aquarids.

Scientific Queries

Meteor showers are named after the constellations they appear to be coming from. In the case of the South Delta Aquarids, the constellation is Aquarius; the Leonids, the constellation Leo; the Perseids, the constellation Perseus; and so on.

But the showers have little to do with the constellations they are named for. Rather, they are produced by bits of dusty debris shed by orbiting comets and asteroids. The Leonids are produced by comet Tempel-Tuttle, the Perseids by comet Swift-Tuttle.

The scientific community is not certain what the parent body of the South Delta Aquarids is. Several competing theories point to different sources.

"The best candidate appears to be a short-period comet known as 96P/Macholz," Bone said.

96P/Macholz is also thought to be the parent comet of the annual Quadrantid meteor shower in early January. But this theory too is controversial, which makes the South Delta Aquarids even more intriguing, Gramer said.

Astronomer Peter Jenniskens with the NASA Ames Research Center in Moffett Field, California, recently proposed that a celestial body—a defunct comet or asteroid—known as 2003 EHI could be the parent of the Quadrantids.

The South Delta Aquarids also appear to be related to North Delta Aquarids, which occur at about the same time but appear to be coming from the northern portion of the constellation Aquarius.

"The river of dust which forms the SDA meteor shower—and the one that forms its sister NDA shower—has probably been diverted and redirected by the gravity of the planets, so that it may be very challenging to ultimately tie it back to whatever its original parent body or bodies were," Gramer said.

Amateur observations of the South Delta Aquarids can help scientists address questions about the relationship between the South Delta Aquarids, North Delta Aquarids, and the other simultaneous showers and the parent body of the meteor shower. Such observations may also reveal how to predict elevated rates in coming years.

"Amateur studies actually provide a majority of the knowledge of what is currently known of this shower," Lunsford said.

According to Bone, the thrill of amateur meteor observing is just watching and recording the activity. "Sometimes nominally well-understood showers can produce unexpectedly high activity, and then it becomes a matter of professional interest to try and understand the underlying reasons," he said.

For more meteor news, scroll down.

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