As if celebrating the cosmic connections of our planet, the annual meteor shower of Lyrids on Monday's Earth Day will fire a silent fireworks display. We explore the origin of the shower and how best to look and photograph it.
Good news for the Lyrids. These annual meteor showers are taking place this year in a dark, moonless sky. Although active by the end of April, peak meteor figures are expected on Sunday morning, April 22, before sunrise.
The Lyrids typically produce 10-20 meteors per hour, which seem to radiate from a point in the sky west of Vega in the constellation Hercules. Before the constellation boundaries were standardized in 1930, the shower's radiation was associated with the constellation Lyra, hence the name.
Most meteor showers are from comets, and the Lyrids are no exception. Her father is the long comet Thatcher (C / 1861 G1) which circles the sun every 415 years. The New York amateur AE Thatcher discovered it on April 6, 1861 with his 4.3-inch refractor. Six years later Johann Gottfried Galle (discoverer of Neptune) counted and found that the comet and the shower were related
The Lyrids are a reliable, if modest, shower, but every 60 years they show one much stronger activity. The last outbreak occurred in 1982 when some observers saw more than 100 meteors per hour. Peter Jenniskens in his book Meteor Shower and her Parents Comet predicts that the next Lyrids thrusts will likely happen in 2040 and 2041. While Comet Thatcher will not come back around the year 2276, forecasters predict that these cyclical outbreaks could be caused by a recent rupture of the comet Thatcher, which has deposited a friable fragment in a 60-year orbit.
While their numbers do not match the more well-known August Perseids, the Lyrids have at least a claim to fame – no modern shower has been recorded so far back in time. Chinese court astronomers reported on 16 March 687 BC. About a Lyrids eruption, when "in the middle of the night stars fell like rain".
In the present day, the Lyrids retain their fame for a different reason. After more than three months of shedding for meteor showers, they burst on the scene like a wave of Spring Robins and open the door for more followers: the Eta Aquarids in May; July's Delta Aquarids; and the Perseids in August.
The best news of all is that the moon will no longer be in the sky for the shower and will remain out of the picture for the maxima of the Perseids, Orionids, Leonids and Geminids. (Okay, the Orionids are being harassed with moonset at 4am, but that will still leave nearly 2 hours of peak observation before dawn.) This makes 2018 an extraordinary year for meteor observation.
Watching the Lyrids is easy. As soon as the thick crescent goes down at one o'clock in the morning, the beaming one will climb up in the eastern sky, high enough to begin your Lyrid Night Watch. Better yet, go to bed early and then get up at about 3 in the morning, when the spotlight in the southeastern sky is about 60 ° high. Without a horizon for cropping showers that cut off the radiators below you will see the maximum possible number.
Maybe my perspective is distorted as we had a big blizzard here in Minnesota, but I suggest dressing warmly in hats, gloves, and boots, as you'll lay still for a while. My favorite observation device is a reclining chair like the one with webbed ones that you probably put away in your garage. Tilt the chair to the southeast, lie down and cover yourself with a blanket or an unpacked sleeping bag. The brighter your observatory is, the more meteors you will see. If you are hardy, start at 2am and watch until dawn (~ 5am). If it's a little less hardy, 3-5 o'clock is perfect.
Lie back, relax and let your worries float as you await the next flaming bite of comet Thatcher. Watching the silence of the night and waiting for every single flash of light provides a soothing form of meditation. Normally, I consider an informal count, but if you want to contribute your observations for meteorologists to better understand and characterize the Lyrids, register for free with the International Meteor Organization here [report] Download .
Lyrids seem to be streaming out of the Radiant a perspective effect caused by the invading meteoroids of comet Thatcher on parallel paths on Earth, much like snowflakes in headlights come from a distant point in the night as you drive down the street. At a speed of 46 kilometers per second, the comet dust hits the atmosphere about 105 kilometers above the earth's surface. It flows through and ionizes the air for a short time to create a fleeting strip of glowing light that we see as a meteor. The Leonids, the fastest of the meteor shower, hit the air at 72 km / sec.
Some of us might want a souvenir from the Lyrids shower in the form of a photo. For this you need a medium to high quality camera and a tripod. Choose a medium to wide angle lens (17-35mm), then set the camera and lens to manual (M setting) and use the live view to focus on a bright star. Next, create an image that contains the spotlight to one side of the field of view. Meteors off blasting leave longer, more dramatic trails. Open the lens to the widest setting (usually f / 2.8, 3.5 or 4), set ISO to 800 or 1600 and expose it for 30 seconds
Check your progress and exposure by clicking on the back Display look. You can manually take one photo at a time or automate the process by using a Intervalometer that allows you to record continuous-time images freehand. There is no better tool for meteor shower photography.
Now we only need good weather. If the maximum of the shower coincides with the day of the earth, there is no better way to confirm the cosmic connection of the planet than to watch sparks fly as we enter cometary dust. May the sky be clear when Sunday morning arrives.