I thought it would be useful to do a quick round up of 2024, now that we’re through the Quadrantids and into the spring quiet period.
In 2024, we made 1,263,868 individual detections from 237 cameras. Just over half of these were matched with other cameras, leading to 109,862 confirmed meteors at an average of 6.5 cameras per meteor. Forty three were classed as fireballs (visual magnitude greater than -4), though none dropped meteorites over land. The longest track was nearly 100km, though the majority of track lengths were between 5 and 10km. Median duration was around 0.5s and the longest was 21s – an earth-grazer that was seen all the way from Croatia to Cardiff.
Unsurprisingly, the Perseids dominated these stats, with around 120,000 detections leading to 8262 matches, with on average nine stations picking up each detection. The next three prominent showers, the Orionids, Quadrantids and Geminids, accounted for around 4000 matches between them. Overall, our cameras detected confirmed meteors from 350 different showers.
Its always interesting to look at the velocity distributions. The geocentric velocity, ie relative to the Earth, ranges from 10 to 75km/s. However the heliocentric velocity, which is the meteoroid’s true velocity around the Sun as it passes the Earth, is more tightly clustered between 25 and 50 km/s. Why is this? Well, the Earth is travelling at around 30km/s in its orbit, so depending on whether a meteor shower hits us head on, or catches up from behind, you have to add or subtract 30km/s from its heliocentric velocity. An object like a comet coming in the Oort cloud would have a heliocentric velocity of around 40 km/s at the Earth’s orbit, hence a combined geocentric velocity of up to 70 km/s, depending on angles. Anything with a geocentric velocity greater than about this is either extrasolar – or more likely bad data !
And what about those unmatched detections? Well, many of them will be single-station detections with no match. Some will be matched, but no viable solution could be found due to factors such as distance, bad angles, calibration errors, etc. Many will be non-meteoric events that sneaked through the filters. It’d be great if someone had time to comb through to see if there are any interesting events.
Finally, how much did this cost? Last year, UKMON’s operating costs were £1,788 of which £255 was for the website and groups.io subscriptions, and the remainder was cloud storage and compute to generate the daily matching and reports. We received donations of £621 (thank you to everyone who donated ) and we received a one-off grant of £3000 from STFC. Further details can be found on the Archive website under About Us / Agendas Minutes and Reports.
So thats a wrap for 2024. This year has started with a bang, with 2500 Quadrantids, 7500 other confirmed matches and a couple of fireballs but there are no major night-time showers now till the Lyrids and Eta Aquariids in late April, and then another lull till the Southern Delta Aquariids and Alpha Capricornids in mid July. Most of the activity from April till July is during daylight, and so you’ll need a radio detector to pick them up. However this lull in shower activity often corresponds with an apparent rise in fireball activity so do keep your cameras on and clear of spiders and vegetation !
There’s more info here, where you can also examine the data by month
https://archive.ukmeteors.co.uk/reports/2024/ALL/index.html
And here’s last years shower statistics report
https://archive.ukmeteors.co.uk/reports/2024/showers/index.html