The American Meteor Society, Ltd. is a non-profit scientific organization founded in 1911 and established to inform, encourage, and support the research activities of both amateur and professional astronomers who are interested in the fascinating field of Meteor Astronomy. Our affiliates observe, monitor, collect data on, study, and report on meteors, meteor showers, fireballs, and related meteoric phenomena. Please note that the AMS does not deal in meteorites.
Meteor Records
Now - I obtained my records via two different subscriptions, can I use the subscription to get to the records that it pulled back? Or must I requery my collection? What is the best practice for sharing that query between client and server?
I hope I'm not missing something obvious here, but executing the Meteor.subscribe function only for its side-effects seems to be losing a very useful piece of information - namely which subscription a record came from. Presumably the names of publications and subscriptions are chosen to be meaningful - it would be nice if I could get to records associated with that name.
What you seem to want to do is maintain two separate collections of records, where each collection is populated by a different publication. If you read the DDP specification, you'll see that the server tells the client which collection (not publication) each record belongs to, and multiple publications can actually provide different fields to the same record.
Here we'll go through what a meteor shower is, how best to see a meteor and provide key dates as to when the major annual meteor showers take place, so you can determine whether a meteor shower is happening tonight or in the not-too-distant future.
Bright trails are often followed by a glowing column of ionised gas called a meteor train, which fades over time. Persistent trains may last for many seconds, becoming distorted by high altitude atmospheric winds.
Spotting meteors during a shower is a pretty easy task to carry out, requiring nothing more than a pair of eyes and something to record your results with. You could even get family or friends to help you complete a scientific record of what you see.
The quiet lulls in activity that typically occur during meteor-viewing sessions are useful times to learn the constellations. However, avoid looking down at charts for prolonged periods because this may cause you to miss trails.
Get involved in real scientific observing by downloading a meteor reporting form from the British Astronomical Association (britastro.org) you can help with its national survey. On the form:
F Train details and time to fade is to record any special qualities about meteor trains. Time to fade records the number of seconds the train takes to become invisible to the naked eye.
In 1920, a farmer was plowing a field near Grootfontein, Namibia when his plow suddenly screeched to a halt. Curious about what he had run into, he dug in the soil to find a large piece of metal. The large metal mass quickly attracted the attention of scientists and others, who identified it as a meteorite and removed the soil around it.
The farmer had discovered a 66-ton iron meteorite - the largest single meteorite ever found and the largest piece of iron ever found near Earth's surface. It is tabular in shape and about nine feet long, nine feet wide and about three feet thick. It was given the name "Hoba" because it was discovered on a farm named "Hoba West."
Hoba is thought to have fallen to Earth about 80,000 years ago. It is composed of about 84% iron, 16% nickel, and trace amounts of cobalt and other metals. An abundance of iron oxides in the soil around the meteorite suggests that it was much larger than 66 tons when it landed and has suffered significant losses from oxidation.
It is surprising that this meteorite is not surrounded by a crater. Objects of this size should punch through the atmosphere at a very high rate of speed and hit Earth with enough force to blast a significant crater. No crater is present around the site of the meteorite. This suggests that it fell to earth at a lower rate of speed than expected. Some scientists believe that the flat shape of the object may be responsible for its low velocity at impact.
The International Meteor Organization (IMO) was founded in 1988 and has more than 250 members now. IMO was created in response to an ever growing need for international cooperation of meteor amateur work.
Based on data collected by observers of the IMO Video Meteor Network, MeteorFlux 2.1 Realtime Viewer allows you to access the latest ZHR graphs of currently monitored active meteor showers:
On 22 August 1888, according to multiple documents found in the General Directorate of State Archives of the Presidency of the Republic of Turkey, a falling meteorite hit and killed one man and paralysed another in what is now Sulaymaniyah in the Kurdistan Region, Iraq.
This constitutes, according to researchers, the first-ever known proof of death by meteorite strike. And it hints there could be more such records out there, hiding in archives, waiting to be discovered.
Earth is not an unassailable fortress. It's under a constant bombardment of space rocks; it's estimated that millions of meteors per day hit the atmosphere. To be fair, not many of them survive atmospheric entry.
But, according to NASA's fireball database, at least 822 have been big enough to explode in the atmosphere since 1988, raining down meteorite debris. And some scientists believe that up to 17 meteors could hit Earth's surface every day.
You'd therefore think that someone, somewhere would have been hit and killed by a falling chunk of space debris over the years, but historical records have been strangely bereft of reliable reports of this occurring.
Even the massive Chelyabinsk meteorite in 2013, which exploded in the atmosphere and rained down chunks weighing up to 654 kilograms (1,442 pounds), didn't kill anyone; all injuries reported were from the effects of the shockwave, not falling meteorite.
According to a 1951 paper published in Popular Astronomy, the difficulty to provide historical evidence "arises not from any dearth of apparently relevant incidents but chiefly from the lack of material evidence that the missiles involved in the accidents were genuinely meteoric and the impossibility of subjecting to critical questioning either survivors or eyewitnesses of the sensational events described."
So, to the best of our knowledge, death by meteorite is vanishingly rare; the only confirmed victim of a meteorite strike is a woman named Ann Hodges, who was napping on her couch in 1954 when the rock fell through her roof and hit her hip. The rock was retrieved, and confirmed to be extraterrestrial in origin. Hodges survived.
After this event, meteorites fell "like rain" from the sky for a period of about 10 minutes on a small village, resulting in the death of one unnamed man, and the paralytic injury of another. In addition, damage to crops was reported - which is consistent with a fireball shockwave.
It's impossible to know the exact altitude, speed, size and location of the fireball. But, based on the villages where it was seen, the researchers believe the meteorite travelled from the southeast before its pieces impacted on a pyramid-shaped hill in Sulaymaniyah.
"This event is the first report ever that states a meteor impact killed a man [..] with the support of three written manuscripts that report an event in such detail up to our knowledge," the researchers wrote in their paper.
In a visual meteor watch the watcher goes outside on a clear dark night, well away from full Moon, and observes the sky for as long as possible, recording what is seen by either writing it down, or by speaking into an electronic voice recorder.
The bulk of the form is set aside for recording details on each individual meteor seen. Use at least one line per meteor when writing up your observations after the watch. In the field, as little time as possible should be spent taking notes on a meteor, but ensure that all the relevant facts are correctly put down. Portable voice recorders can also be used for this purpose, although they need to be protected so as not to malfunction when in damp, cold, outdoor conditions. The form columns, and hence items to look out for, are as follows.
Accurate visual meteor work requires observations from individuals, but several individuals can observe from one site, each recording their own data only. Conversation in such a group should not be too distracting for the watchers, but can be very useful in helping everyone stay alert.
Casual observations of meteors may be made by chance, perhaps when out checking the sky, or may be carried out by individuals or groups who are outdoors at night, but who are not intending to carry out a formal meteor watch. These data can have some use too, providing they are promptly reported to the Section. This is most important for fireballs, but reports on the run-of-the-mill objects seen during a known time-interval can provide an interesting comparison with those made by observers who have been sky-gazing especially for meteors.
Another type of casual watch is that carried out from indoors, perhaps through a window or a conservatory roof. For meteor enthusiasts stuck indoors through illness or injury, this can provide a welcome boost to morale, providing a night around a major meteor shower maximum is selected. The restricted field of view will naturally hamper observing, but when meteor rates are notably high, such as around January 2-4, August 10-14 or December 12-14, very acceptable meteor numbers can be spotted.
Fireball brightness estimates are never easy, as convenient comparison objects are rarely close by. Above magnitude -5 (Venus), there is only the Moon as a guide, and converting from an area of light (the Moon) to a point (the meteor) brings its own problems, so the brilliance of such meteors is usually more guess than estimate.
This information together with the time it was detected was passed to the UK Fireball Alliance ( ) who have coordinated data from a range of sources such as microphone and video recordings, to determine where the meteor was likely to have made landfall. 2ff7e9595c
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