Normally a small number of “sporadic” meteors can be seen each hour of a moonless night. Sporadics are likely to be seen in any part of the sky. During a shower, the number of meteors visible may increase considerably. The meteors will appear to originate from a small area of the sky, called the radiant.
The spreading out from the radiant is a perspective effect due to the meteors travelling in parallel lines but as they approach the observer they appear to fan out.
The shower is named after the constellation which contains the radiant. In general, the meteor trails do not start from the radiant, but a few degrees from it.
Lyrid Meteor Shower
In 2021, the likely peak morning for the Lyrids is Thursday morning, April 22. But the mornings from 19 – 23 should be good, too. The moon is waxing – staying out longer after dark each night – so you will want to watch the time of moonset carefully. The Lyrids are active each year from about April 16 to 25.
Because this shower’s radiant point is so far north on the sky’s dome, the star Vega rises only in the hours before dawn, for you. It’ll be lower in the sky for us in the south so we are best to look out before dawn.
It is named Lyrid because the meteors seem to come from the constellation Lyre.
The Lyrid meteor shower has the distinction of being among the oldest of known meteor showers. Records of this shower go back for some 2,700 years. The ancient Chinese are said to have observed the Lyrid meteors falling like rain in the year 687 B.C. That time period in ancient China, by the way, corresponds with what is called the Spring and Autumn Period (about 771 to 476 B.C.), which tradition associates with the Chinese teacher and philosopher Confucius.
Comet Thatcher (C/1861 G1) is the source of the Lyrid meteors. Every year, in late April, our planet Earth crosses the orbital path of this comet which last visited the inner solar system in 1861, and is not expected to return until the year 2276.
Pi-Puppid Meteor Shower
The pi Puppids are a meteor shower associated with the comet 26P/Grigg-Skjellerup. The ?-Puppid meteor shower will be active from 15 April to 28 April, producing its peak rate of meteors around 23 April.
The meteor stream was viewable around April 23 but only in years around the parent comet’s perihelion date, the last being in 2003. However, as the planet Jupiter has now perturbed the comet’s perihelion to beyond Earth’s orbit it is uncertain how strong the shower will be in the future.