Meteors enter our atmosphere on a regular basis. On a normal night you can typically see a few sporadic meteors per hour. They were brought back into the news and public spotlight this year due to a meteor crash in Chelyabinsk, Russia on 15th February in which up to 1200 people suffered injuries from flying glass and debris as windows exploded from the shockwave. The toll is believed to be the largest number of people ever injured by space debris.
The early hours of this morning should supposedly see the best viewings of the Eta Aquarids meteor shower. There are 9 major (Class 1) meteor showers each year.
So why am I blogging about this? Well, meteor activity makes for quite an interesting map subject. Meteors can theoretically fall anywhere but meteor strikes do appear to be most common across the USA.
There seems to be some confusion online as to whether the heat map above is of meteor activity (which may include numbers sighted) or as I think it is, meteor strikes, i.e. those recorded after impact with the ground. Carl Franzen (The Verge) seems to clarify this as the latter stating that ‘the map shows recorded points on Earth that have been struck by meteorites since 2,300BC.’ He also clarifies that it doesn’t include data for meteorites that haven’t left any evidence, landed in an ocean, or remain undiscovered.
I originally came across it on a Russian blog post but further research and a blog post by Gary Gale (co-director of HERE Maps by Nokia) led me to the map’s creator – Javier de la Torre, co-founder of CartoDB and Vizzuality.
De la Torre created the map using CartoDB’s mapping software, which relies on the crowdsourced OpenStreetMap for its base layer. The meteorite impact site data – 34,513 individual points of impact in total – came from the Meteoritical Society, an international non-profit scientific collaboration.
Web publication The Verge claims De la Torre created the map for the website of newspaper The Guardian, and that it only took him 30 minutes! However fellow blogger Daria Ilkina suggests that De la Torre may have been inspired by a map using the same data that already appeared on The Guardian’s website.
Either way, it really is a wonderful map but perhaps the confusion between articles on its content and reason for being highlights the need for a title and legend and/or an explanation. The original interactive version is on the CartoDB website. It is clear that the US for whatever reason appears to attract more meteors. Again it is not clear but I think the heat map is also displaying the debris falls, this would explain the lighter coloured, larger ‘perfect circles’.
The next map, of which the origins are unknown, shows the masses of fallen meteorites:
The next map, which is a more ‘zoomed in’ view of De la Torre’s CartoDB-based interactive map, highlights meteor strikes across the UK and North Western Europe:
Meteorwatch have a live meteor map (above) using tweeted sightings over Google Maps imagery. Unfortunately there is little further information.
The American Meteor Society encourages people in the US to notify them of meteor fireballs, a far rarer occurance than regular meteor dust particles. They have kept records of the past eight years of activity and in February produced the fireball sightings map below:
Perhaps it is the astronomer in them, but it seems that for such organisations, plotting such events on a satellite image seems to be the overwhelming trend. Whilst useful it seems a shame the 8 years of data cannot be presented in the form of a proper map. The topic lends itself so well to a good cartographic creation.
Some enthusiasts even try to map the position of the radiants – the position in the sky where the majority of meteors in a shower appear to originate from – for meteor shower watchers. As a cartographer of the land and occasionally the sea, I don’t really have any expertise in the field of sky mapping so I shall refrain from any critiquing!
In the past year or two, there seems to have been a trend in American static web cartography for showing areas of coverage as 3-dimensional almost fluid-like polygons. The next map example is typical of this trend. Love it or hate it the map shows the viewing conditions across America for last month’s Lyrid meteor shower as part of an online weather forecast.
This really is a fascinating subject, all of the data is out there, so perhaps more cartographers can follow Javier’s lead and turn it into beautiful maps.
For those of you having trouble sleeping, meteors can be seen with the naked eye and NASA have the following advice:
‘Lie flat on your back on a blanket, lawn, chair or sleeping bag and look up, taking in as much of the sky as possible. After about 30 minutes in the dark, your eyes will adapt and you will begin to see meteors. Be patient – the show will last until dawn, so you have plenty of time to catch a glimpse.’