Lyrids Meteor Shower 2014
UPDATE: the peak of this year’s Lyrids is expected at 1700 UT on 22 April, so for UK meteorwatchers the best time is pre-dawn on 22 April or after midnight on 23 April. Via @popastro
Starting tonight and peaking next week on 22/23 April 2014 is our spring season’s best meteor shower, the Lyrids. It’s not nearly as dramatic as the Big Three meteor showers – the Perseids in mid-August, the Geminids in mid-December, and the Quadrantids in early January – but dedicated meteorwatchers will catch glimpses of plenty of shooting stars overnight around or after midnight on 21/22 or 22/23 April.
The peak rate (more correctly the Zenith Hourly Rate) of the Lyrids is around 20 meteors per hour, but that’s under ideal conditions: 100% clear skies, zero light pollution, and the radiant (the point at which the meteors appear to emerge from) at the zenith (directly overhead). In the nights leading up to the peak you can still expect to see a few but the ZHR is much lower, around 5 meteors per hour.
So how many Lyrids can we expect to see from the UK next week at the peak? To work this out we’ll have to make some assumptions, and then crunch some numbers.
Let’s assume clear skies at least. Then we’ll assume that the peak will fall either some time between dusk on 21 April and dawn on 22 April or some time between dusk on 22 April and dawn on 23 April (currently the suggestion is that it’ll be pre-dawn on 22 April, but it’s worth watching out on both nights). Finally we’ll assume that the ZHR at the peak will be around 20.
The only limiting factors then are (a) the height of the radiant above the horizon, which changes as Lyra rises in the east, climbing high in the south by dawn; and (b) the light pollution
|Time||Height of Radiant*||Hourly rate if peak occurs at this time|
|2200 21 or 22 April||18°||6|
|2300 21 or 22 April||25°||8|
|0000 21 or 22 April||32°||11|
|0100 22 or 23 April||40°||13|
|0200 22 or 23 April||49°||15|
|0300 22 or 23 April||57°||17|
|0400 22 or 23 April||65°||18**|
|0500 23 April||71°||19**|
* This is based on my observing location in Glasgow, but it’ll only be a few degrees out .
** The last quarter Moon rises around 0330 and so will create enough light pollution to significantly reduce these numbers.
|Location||Limiting Magnitude||Divide above hourly rates by…|
These graphs of previous years show the how the Lyrids activity rate increases and decreases with time centred round a peak on 22 or 23 April: