Eta Aquarid Meteor Shower Hailing from Halley's Comet to Light up Night Sky This Week: How and When to Watch

The Eta Aquarid meteor shower, which is caused by the debris from Halley's Comet, reaches its peak this week.

According to the American Meteor Society (AMS), this will occur on May 5 and 6, although the shower has a relatively broad peak—meaning activity is usually good for several days either side of the maximum.

The shower is best viewed from the southern tropics, where up to 40 meteors can be seen per hour in good viewing condition, EarthSky reported.

Nevertheless, the shower is still visible in the northern hemisphere, although it may only produce rates of 10 to 30 meteors per hour from the equator northward, according to the AMS. Those living in more southerly U.S. states are usually able to see more meteors than those in northern states.

The Eta Aquarids are usually active between April 19 and May 28 every year, and are characterized by swift meteors that often leave persistent trains—trails of vaporized material that can glow for several minutes.

Meteor showers are celestial events during which several meteors appear to originate from a single point in the night sky—what's known as the radiant. These events take place when the Earth passes through streams of cosmic debris left behind by comets and, in rare cases, asteroids.

In the case of the Eta Aquarids—so-named because their radiant is located in the constellation Aquarius, whose brightest star is Eta Aquarii—the source of the shower is Halley's Comet, which is in a 76-year-long orbit around the sun.

Eta Aquarid meteors, California
Stock image: Eta Aquarid meteors as seen over Half Dome, California, Yosemite National Park, in 2014. iStock

The debris left behind by the comet also circles our star, and the Earth passes through this stream of ice and dust in May and October every year, leading to the Eta Aquarid and Orionid meteor showers, respectively. The Aquarids are the outbound pieces of debris from the comet, while the Orionids are the inbound particles.

Meteors are meteoroids—space objects ranging in size from grains of dust to small asteroids—that enter the Earth's atmosphere and burn up at extremely high speeds. The streaks of light we see in the sky when this happens are popularly referred to as "shooting stars."

In the case of the Eta Aquarids, the meteors burn up while traveling at speeds of nearly 150,000 miles per hour.

According to the AMS, most people in the northern hemisphere only have a two-hour window to view these meteors. The organization recommends looking toward the eastern half of the sky during the last two hours before dawn.

While you won't need any special equipment to see the meteors, you will need a clear sky. Furthermore, the best views will be in areas away from city lights with low levels of light pollution.

Unfortunately, the moon will be around 90 percent full during the peak of the meteor shower this year, meaning its light will interfere with observations. However, observers can increase their chances of seeing meteors by viewing when the moon is low in the sky before the first light of dawn arrives.