Lyrid Meteor Shower Radiant Point
   HOME

TheInfoList



OR:

The April Lyrids are a
meteor shower A meteor shower is a celestial event in which a number of meteors are observed to radiate, or originate, from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extre ...
lasting from April 16 to April 25 each year. The radiant of the meteor shower is located in the constellation
Lyra Lyra (; Latin for lyre, from Greek ''λύρα'') is a small constellation. It is one of the 48 listed by the 2nd century astronomer Ptolemy, and is one of the modern 88 constellations recognized by the International Astronomical Union. Lyra was ...
, near its brightest star,
Vega Vega is the brightest star in the northern constellation of Lyra. It has the Bayer designation α Lyrae, which is Latinised to Alpha Lyrae and abbreviated Alpha Lyr or α Lyr. This star is relatively close at only from the Sun, an ...
. The peak of the shower is typically around April 22 each year. The source of the meteor shower are particles of dust shed by the long-period Comet C/1861 G1 Thatcher. The April Lyrids are the strongest annual shower of meteors from debris of a long-period comet, mainly because as far as other intermediate long-period comets go (200–10,000 years), this one has a relatively short orbital period of about 415 years. The Lyrids have been observed and reported since 687 BC; no other modern shower has been recorded as far back in time. The shower usually peaks around April 22 and the morning of April 23. Counts typically range from 5 to 20 meteors per hour, averaging around 10. As a result of
light pollution Light pollution is the presence of unwanted, inappropriate, or excessive use of artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting, during the day ...
, observers in rural areas will see more than observers in a city. Nights without the
Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
in the sky will reveal the most meteors. April Lyrid meteors are usually around
magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...
+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 planets steer the one-revolution dust trail of the comet into Earth's path, an event that happens about once every 60 years. This results in an April Lyrid meteor outburst. The one-revolution dust trail is dust that has completed one orbit: the stream of dust released in the return of the comet prior to the current 1862 return. This mechanism replaces earlier ideas that the outbursts were due to a cloud of dust moving in a 60-year orbit. In 1982, amateur astronomers counted 90 April Lyrids per hour at the peak and similar rates were seen in 1922. A stronger storm of up to 700 per hour occurred in 1803, and was observed by a journalist in
Richmond, Virginia (Thus do we reach the stars) , image_map = , mapsize = 250 px , map_caption = Location within Virginia , pushpin_map = Virginia#USA , pushpin_label = Richmond , pushpin_m ...
:
Shooting stars. This electrical 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 ...
Another such outburst, and the oldest known, the shower on March 23.7, 687 BC (proleptic
Julian calendar The Julian calendar, proposed by Roman consul Julius Caesar in 46 BC, was a reform of the Roman calendar. It took effect on , by edict. It was designed with the aid of Greek mathematicians and astronomers such as Sosigenes of Alexandr ...
) was recorded in '' Zuo Zhuan'', which describes the shower as "On the 4th month in the summer in the year of xīn-mǎo (of year 7 of King Zhuang of Lu), at night, (the sky is so bright that some) fixed stars become invisible (because of the meteor shower); at midnight, stars fell like rain." (夏四月辛卯 夜 恆星不見 夜中 星隕如雨) In the
Australian Aboriginal astronomy Australian Aboriginal astronomy is a name given to Aboriginal Australian culture relating to astronomical subjects – such as the Sun and Moon, the stars, planets, and the Milky Way, and their motions on the sky. Traditional Aboriginal cu ...
of the
Boorong The Wergaia or Werrigia people are an Aboriginal Australian group in the Mallee and Wimmera regions of north-Western Victoria, made up of a number of clans. The people were also known as the Maligundidj (in the Wotjobaluk language) which means ...
tribe, the Lyrids represent the scratchings of the
Mallee fowl The malleefowl (''Leipoa ocellata'') is a stocky ground-dwelling Australian bird about the size of a domestic chicken (to which it is distantly related). It is notable for the large nesting mounds constructed by the males and lack of parental ca ...
(represented by
Vega Vega is the brightest star in the northern constellation of Lyra. It has the Bayer designation α Lyrae, which is Latinised to Alpha Lyrae and abbreviated Alpha Lyr or α Lyr. This star is relatively close at only from the Sun, an ...
), coinciding with its nest-building season.


Notes and references


External links


Worldwide viewing times for the 2016 Lyrids meteor shower
(Spacedex Apr 15, 2016)
Lyrids results for 2012

Lyrids in 2012
(
International Meteor Organization The International Meteor Organization (IMO) was formally founded in 1988 from predecessor gatherings over many years. IMO has several hundred members and was created in response to an ever-growing need for international cooperation on amateur and ...
)
Everything you need to know: Lyrid meteor shower
(Earthsky Apr 04, 2013)

(NASA Marshall Space Flight Center)


2009 Meteor Calendar (Gary Kronk)
* NASA Orbital diagram for come
C/1861 G1 (Thatcher)
(source of the Lyrids)
Lyrid Meteor Shower at Constellation Guide
{{Meteor showers Meteor showers April events