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Lyrids Meteor Shower 2014

April 16, 2014 3 comments

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.

Meteors

Meteors

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…
Bright Urban 3.5 8
Urban 4 6
Bright Suburban 4.5 4
Suburban 5 3
Rural 6 1.5
Truly Dark 6.5 1

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:

Lyrids Activity 2011

Lyrids Activity 2011

lyr2012overview

Lyrids Activity 2012

lyr2013overview

Lyrids Activity 2013

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Meteor Showers for 2011-2012: Ones to watch

January 4, 2011 8 comments

With the Quadrantids meteor shower that has just past yielding around 100 meteors per hour in near-perfect New Moon conditions, which showers of the next two years will give us as good a display?

Meteor Shower

There are a few regular, dependable showers that can be relied on to put on a good show year after year, given a good Moon phases, so let’s concentrate on those:

Lyrids 2011
The Lyrids peak this year on April 21/22, only three days after the Full Moon, making conditions far from ideal. The ZHR is around 20, but under bright Moon conditions this will be much reduced, so that from the UK you might only see a few Lyrids per hour.

Persieds 2011
The Perseids peak on 12/13 August 2011 coincides exactly with a Full Moon, making this shower pretty much a write-off in 2011.

Orionids 2011
The Orionids peak occurs on 21/22 October 2011 just after the last quarter Moon, with the Moon rising a little after midnight, just as the meteor shower radiant is gaining height. Again, far from ideal.

Leonids 2011
The Leonids peak on 17/18 November occurs during a last quarter Moon, which unfortunately is smack bang in the direction of Leo, and so will obscure many of the Leonids in 2011

Geminids 2011
The Geminids peak on 13/14 December 2011 will likewise be completely obscured by an almost-full Moon in Gemini.

Quadrantids 2012
The Quadrantids peak on 3/4 January 2012 will feature a waxing gibbous Moon which won’t set until 0400.

Lyrids 2012
The Lyrids peak on 21/22 April 2012 is the first major shower peak in 15 months where the Moon is absent, meaning that you should get good views of this shower which has a ZHR of only around 20.

Persieds 2012
The Perseids peak of 12/13 August 2012 will feature a thin waning crescent moon that’s visible in the sky from midnight, obscuring some of the Perseids. Here’s my up-to-date guide to the Perseids 2012.

Orionids 2012
The Orionids peak on 21/22 October 2012 is pretty much Moon-free from around 2330, as the Moon sets.

Leonids 2012
The Leonids peak on 17/18 November 2012 will also be Moon free from early evening, and so presents an opportunity to see a few Leonids.

Geminids 2012
Rounding off this two year run of poor Moon conditions for meteor showers, we end with the Geminids on 13/14 December, coinciding wonderfully with a New Moon on 13 December, meaning conditions will be near perfect.

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