Night sky observers will get a special treat this week: dirt from Halley’s comet’s tail will set the stage for a meteor shower that will delight the naked eye with streaks of shooting stars. According to NASA, Eta Aquarid meteors are known for their speed. When traveling about 148,000 mph into Earth’s atmosphere, fast meteors can leave glowing “trains” that last for several seconds to minutes. These trains are really glowing pieces of dirt in the wake of the meteor. In general, 30 Eta Aquarid meteors can be seen per hour during their peak.
The pieces of space debris that interact with the Earth’s atmosphere to create the Eta aquariums originate from Halley’s comet. NASA’s Jet Propulsion Laboratory reports that each time Halley returns to the inner solar system, its core throws a layer of ice and rocks into space. The dust grains eventually become the Eta aquariums in May and the orionids in October if they collide with the Earth’s atmosphere.
While waste from the comet will light up the night sky this week, don’t expect to see Halley’s Comet itself for a while. Halley takes about 76 years to orbit the sun once. The last time Halley was seen by random observers was in 1986; it will not enter the inner solar system again until 2061.
While the comet will not be exhibited for another 40 years, Eta Aquarids will put on a good show around the earth. The best view of most meteors should be before dawn on Wednesday, May 5th; however, the meteor showers will begin on May 4 and linger through until May 6. Before dawn hours in both the northern and southern hemisphere is the best time to see; of the hemispheres, the southern hemisphere will have better odds of seeing shooting stars than the northern hemisphere.
The best viewing spot is far away from sources of light pollution: city and street lighting can block the faint streaks that would be visible on an otherwise clear, dark night. Astronomers recommend that observers lie flat on their backs with their feet facing east. When you look up at the clear, dark sky, your eyes must get used to the poor light conditions and you must be able to see the meteors rising above the night sky. Of course, in addition to being in an area without light pollution, you must also be in an area without clouds. (See local forecasts for your area to see if the sky will be cloudless in your field of vision here.)
A meteor is a space rock – or meteoroid – that enters the Earth’s atmosphere. When the space rock falls to the ground, the resistance of the air on the rock makes it extremely hot, making a shooting star visible in the sky. The bright stripe is actually not the rock, but rather the glowing hot air when the hot rock zips through the atmosphere.
While meteor showers will be interesting for both meteorologists and non-meteorologists, meteors actually have nothing to do with the weather. The term “meteorology” probably originated in 340 BC, when the Greek philosopher Aristotle wrote a book on natural philosophy entitled “Meteorologica”. This philosophical work included knowledge of what was known about precipitation, lightning, thunder, geography, chemistry, and astronomy. The manuscript was called “Meteorologica” because in those days any particle that fell from the sky was called a meteor. Today, astronomers and other space scientists study extraterrestrial meteors, while meteorologists study so-called “hydrometeors,” which are particles of water and ice in the atmosphere. Apart from the old link thanks to Aristotle, there are no physical connections between meteor showers and weather on Earth.