Lyrids
Encyclopedia
The Lyrids are a strong meteor shower
Meteor shower
A meteor shower is a celestial event in which a number of meteors are observed to radiate from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller...

 lasting from April 16 to April 26 each year. The radiant
Radiant (meteor shower)
The radiant or apparent radiant of a meteor shower is the point in the sky, from which meteors appear to originate. The Perseids, for example, are meteors which appear to come from a point within the constellation of Perseus....

 of the meteor shower is located in the constellation Lyra
Lyra
Lyra is a small constellation. It is one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations recognized by the International Astronomical Union. Its principal star, Vega — a corner of the Summer Triangle — is one of the brightest...

, peaking at April 22—hence they are also called the Alpha Lyrids or April Lyrids. The source of the meteor shower is the periodic Comet C/1861 G1 Thatcher. The Lyrids have been observed for the past 2600 years.

The shower on May 22, 687 BC (proleptic Julian calendar) was recorded in Zuo Zhuan
Zuo Zhuan
The Zuo Zhuan , sometimes translated as the Chronicle of Zuo or the Commentary of Zuo, is among the earliest Chinese works of narrative history and covers the period from 722 BCE to 468 BCE. It is one of the most important sources for understanding the history of the Spring and Autumn Period...

, which describes the shower as "On day xīn-mǎo
Sexagenary cycle
The Chinese sexagenary cycle , also known as the Stems-and-Branches , is a cycle of sixty terms used for recording days or years. It appears, as a means of recording days, in the first Chinese written texts, the Shang dynasty oracle bones from the late second millennium BC. Its use to record years...

 of month 4 in the summer (of year 7 of King Zhuang of Lu), at night, fixed stars are invisible, at midnight, stars dropped down like rain." (夏四月辛卯 夜 恆星不見 夜中 星隕如雨)

The shower usually peaks on around April 22 and the morning of April 23. Counts typically range from 5 to 20 meteors per hour, averaging around ten. Observers in the country will see more, observers in the city fewer.

Lyrid meteors are usually around magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...

 +2. However, some meteors can be brighter, known as "Lyrid fireballs", cast shadows for a split second and leave behind smokey debris trails that last minutes.

Occasionally, the shower intensifies when the Earth passes through a thicker part of the dust trail, resulting in a Lyrid meteor storm. In 1982, amateur astronomers counted 90 Lyrids per hour. A stronger storm occurred in 1803, observed by a journalist in Richmond, Virginia
Richmond, Virginia
Richmond is the capital of the Commonwealth of Virginia, in the United States. It is an independent city and not part of any county. Richmond is the center of the Richmond Metropolitan Statistical Area and the Greater Richmond area...

:


"Shooting stars. This electrical [sic] phenomenon was observed on Wednesday morning last at Richmond and its vicinity, in a manner that alarmed many, and astonished every person that beheld it. From one until three in the morning, those starry meteors seemed to fall from every point in the heavens, in such numbers as to resemble a shower of sky rockets ..."
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