Seven witness near Zurich reported a rumbling boom sound shortly after the fireball appeared. A witness outside of Zurich described the boom by saying, "About two minutes after the fireball there was a considerably strong sonic boom.
The February 2015 issue of the IMO Journal is now in print. It will be mailed shortly and subscribers can also immediately access the journal in PDF format. The contents this month:
Front cover photo: Bright meteor on 2013 August 24 at 22h30m UT from Jura mountains, Switzerland. Photo courtesy: Jonas Schenker.
If you see a fireball in the night sky, you can now report it to the IMO through our new fireball form! Translated into more than 25 languages, the form guides you through describing what you saw in a way that provides useful information to astronomers studying meteors. The information you provide can be combined with that of other eye-witnesses to give a good estimate of the trajectory of the fireball, and to help determine if a ground fall occurred.
Assuming no specialist astronomical knowledge or observing experience, the form easily takes you through the process of reporting a fireball sighting in detail. The information gathered from the submitted reports is collected into a public database which can be searched for particular events.
A large team of IMO volunteers has been hard at work translating the fireball form into more than 25 languages, and the IMO is now busy publicising it to local astronomical societies and observing groups around the world. Large fireball events often excite local media; if such an event happens in your region you can help by telling people about the form so that they can report what they saw.
If you would like to contribute a new translation in a language not already covered, or spot a mistake in the text of the form in your native language, please get in touch so that we can fix it, or follow the instructions to translators.
The IMO fireball report can be easily customized and branded for amateur societies, observatories, institutions or other astronomical organizations who receive fireball reports and enquiries from the public (see the Turkish Uzaybimer version for example, you may need to clear your browser cache). For more details, and to set up an account for your organization, please contact firstname.lastname@example.org.
If you would like to test the form without submitting a false event to the database, please use the test version of the form.
Happy fireball spotting!
Never mind the new year fireworks, the start of 2015 happened with an even bigger bang, at least if you happened to be in Romania, Moldova or the Ukraine. The early hours of January 7th saw a massive fireball over the region, culminating in an explosion loud enough to wake people, and causing many to call the emergency services to report the event. In Romania reports of sightings have come in from across the country, putting the time of the explosion at 3:05 EET (01:05 UT), with people hearing the explosion in the counties of Buzau, Vrancea and Covasna.
So far over 50 recordings and eye witness reports have been collected by the IMO, many from surveillance cameras recording sudden brightening of whatever outside area was being monitored. A compilation of videos of the event, as recorded by security cameras, has been posted on youtube. The map below shows the location of the reports received so far, red dots are from surveillance cameras, the blue markers are visual reports from witnesses, and the green dots are reports from those who heard the terminal explosion.
Image by Raul Truta, compiled from online reports.
Red: detections by cameras, blue: visual observations, green: reports of sound heard.
The reports from Romania of the January 7th fireball put the maximum apparent magnitude of -16, brighter than the full Moon (-13). Roughly one in 1,200 meteors is brighter than magnitude -5, while only one on 12,000 meteors reaches magnitude -8 or brighter, so fireball events like this one are rare.
So far, information on the event is sparse. The explosion appears to have occurred at a height of roughly 55 kilometres and, although some fireballs do result in meteorite fragments reaching the ground, it is likely that in this case the meteoroid completely disintegrated.
Whether a fall occurs or not, the details of events like this can only be determined from combining the information from many eyewitness reports. If you see a bright fireball event like this, you can help researchers by reporting what you saw in as much detail as possible. You can find further information on meteors and other related events, and advice on how to observe and report them, visit the observations section of the IMO website.
The December 2014 issue of the IMO Journal is now in print. It will be mailed shortly and subscribers can also immediately access the journal in PDF format. The contents this month:
Front cover photo: Bright fireball on 2014 February 24 at 01h45m UT from Milton, VT, USA. Photo courtesy: Ethan Rogati.
The October 2014 issue of the IMO Journal is now in print. It will be mailed shortly and subscribers can also immediately access the journal in PDF format. The contents this month:
Front cover photo: Bright meteor on 2014 May 29 at 03h33m UT from Observatorio del Teide, Tenerife, Spain. Photo courtesy: Jürgen Rendtel.