People say that April showers bring May flowers, but have you ever considered meteor showers? We are in the midst of the annual Lyrid meteor shower, and it is one of the oldest meteor showers ever observed with sightings dating back to 687 BC. In 2022, the shower is expected to peak on the night of 4/21-4/22.
Meteor showers are caused by comets composed of dust, rock, and ice leftover from the formation of the solar system. Comets are usually only a handful of miles wide but they also orbit around the sun like our planets, although comets do so in an elongated elliptical shape. During their orbit, comets shed debris and leave behind a trail of cosmic dust along their trajectory. These debris particles, called meteoroids, often weigh less than 1-2 grams which is roughly around the weight of a penny, and range from the size of a small pebble to a grain of sand.
In our orbit around the sun, Earth periodically crosses paths with these trails of meteoroids left behind by various comets. As meteoroids and debris collide with the Earth's atmosphere, some enter our sky as meteors where the atmospheric friction heats and burns meteoric particulates away, ionizing the atmospheric gas around them and lighting up into streaks. These bright streaks of light make up the events we recognize as meteor showers.
For the Lyrid showers, the responsible celestial body is the Comet C/1861 G1 Thatcher. It gets its name from A. E. Thatcher, a scientist who discovered this comet on April 5, 1861. The “C†in its name comes from the fact that comet Thatcher is categorized as a long-period comet, which means its orbital period around the sun is longer than 200 years (comet Thatcher orbits around the sun every 415.5 years). 1861 is designated for the year of discovery, the letter “G†stands for the first half of April, and “1†means that this comet was the first comet to be discovered in this period. Our atmosphere comes across comet Thatcher's trajectory every April, with visible showers near the constellation Lyra, hence the name Lyrid Showers for this annual event.
Avenues such as the International Space Station enable us to gain a better understanding of our extraterrestrial space. With the collective work of scientists and researchers, it is possible to predict the number of visible meteors in one hour of peak activity, termed the zenithal hourly rate (ZHR). The calculated ZHR for the April Lyrids is around 18. This means that you may expect to see a meteor every 3 to 4 minutes under perfect conditions with zero light pollution and full scope of vision. The ZHR varies across different settings dropping as low as 3 in a city sky with a full moon.
There have been 3,743 comets identified thus far. With so many comets orbiting around space, the Lyrid shower marks just a single event of many throughout the year. In fact, there are about 100 well-established meteor showers from which the American Meteor Society lists some of the best shows to watch out for. The Perseids will light up the sky in August with a ZHR of 100, and Geminids will follow in December with a ZHR of 120. As such, if you miss the April Lyrids, you may want to plan to catch the flashier shows with a higher ZHR later this year.
For best viewing, it is critical to reduce light pollution around you. This often entails traveling outside the city into rural areas to open fields, like the Iron Horse nearby Athens. Be sure to check the site beforehand for any safety precautions and stay aware of your surroundings. Also, be sure to tune into your favorite weather channel – a full moon or a cloudy overcast may compromise your ability to catch a glimpse of the glimmer.
Timing is also important. The real show begins between midnight and dawn due to the Earth's orientation relative to the sun and outer space. Once you get to a safe location on a clear night, peer into the atmosphere near the constellation Lyra. You will notice more and more stars coming into your field of vision as your eyes gradually adjust to the night sky. Keeping in mind that it can take up to 30 minutes for your night vision to adjust, kick back, relax, and enjoy the show. Bonus: binoculars are not necessary to enjoy this galactic firework.
Meteor showers will come around again and again as we drift through this cosmic space. Nonetheless, I invite you to go explore the night sky tonight.
About the Author
June Haeun Kim is a UGA graduate student in the Department of Biochemistry and Molecular Biology. She researches protein lipidation, a cellular process that is associated with human diseases like cancer. Outside of the lab, June enjoys exploring local parks around Athens, binge-watching The Amazing Race, and building new playlists for her next road trip. You can reach June at junehaeunkim@uga.edu.
