The 2020 Lyrid meteor shower occurs 14 – 30 April, with peak activity in the very early hours of 22 April. The shower can be spotted every year due to Earth passing through the dust spread around the orbit of comet C/1861 G1 Thatcher, with Lyrid meteor trails appearing to come from a radiant near to the star Vega (Alpha (α) Lyrae).
A fortunate timing of new Moon on 23 April means conditions for this year’s display are optimal.
What is a meteor shower?
We see a meteor in the sky when a small particle – on average about the same size as a grain of sand – vaporises in Earth’s atmosphere. The path of light across the sky is known as a meteor trail.
Most meteor showers are associated with comets, but some are linked with asteroids. As a comet repeatedly orbits the Sun, it spreads dust around the orbit.
Read more about meteor showers:
Earth passes through these dust streams as it orbits the Sun, causing particles to vaporise in the atmosphere. When this happens, the number of trails we can see increases. We experience peak activity of meteor showers when Earth is passing through the most dense section of the stream.
Meteor trails appear to come from a specific area of the sky, which is known as the ‘radiant’. This slowly moves over the duration of the shower.
The constellation in which peak activity appears to occur is what gives each meteor shower its name. You might have heard of the Perseid meteor shower, for example, which shows peak activity when the radiant is in the constellation Perseus.
A new Moon will provide favourable conditions for observing the 2020 Lyrids meteor shower. Credit: Pete Lawrence
What is the Zenithal Hourly Rate?
Zenithal Hourly Rate (ZHR) is a way of comparing meteor showers and isn’t intended to represent expected visual rates.
It refers to the amount of meteors you might expect to see over the course of an hour during the peak, assuming the radiant is directly overhead and you are observing under a perfectly clear, dark sky and no visual obstructions.
What do I need to do to view a meteor shower?
Locate the radiant (see above) and look away from it rather than directly at it. You should be able to spot meteors flying in the opposite direction.
Comfort is important, so we recommend a garden chair, recliner or sunbed to avoid neck strain caused by standing and looking upwards for long periods.
Wrap up warm, even if temperatures are fairly mild at the session’s start.
Give your eyes at least 20 minutes to adapt to the darkness before you start a watch.
Ideally you would want to find a dark location, free from stray light, but given current circumstances a back garden will have to suffice. Perhaps you could ask neighbours to turn off any outdoor lights etc. to help make conditions as dark as possible.
You could even tell them what you are doing and get them to join in from their garden. See how many you can spot and compare notes the following day.
In pictures: the Perseid meteor shower