Meteors with Curved Paths
The movement of each meteor is tracked using its predicted trajectory. The science behind meteor trajectory calculations is rather long, so we will not get into it right now. The important thing about trajectories is that they are supposed to be straight. Indeed, most meteoroids do fall in straight lines. However, there are always some exceptions.
Astronomy differentiates between three types of anomalous meteor paths – curved, kinked, and spiral (wavy). As opposed to straight paths, the three mentioned paths all have unique characteristics, origins, and reasons for such trajectory. Here are the three types of non-linear paths in greater detail.
Curved, Kinked, or Wavy?
Curved meteor paths are the most common manifestation of anomalous meteor paths. The question of curvy paths was only a speculation for many years due to the nature of observation. Namely, in the early stages of astronomical observations, scientists primarily relied on their eyes. Only with the introduction of modern sophisticated technology did we gain more opportunities to observe meteors from a different perspective. And once we put to use the technology, we realized that curved paths were real.
The earliest report of a meteor with a curved path dates from 1885. B.J. Hopkins recorded in Monthly Notices of the Royal Astronomical Society his observation of a meteor that fell in 1879. According to him, the “bright yellow meteor” had a “zigzag path with two bends”. The question of non-linear paths is still open to this day. One of the possible theories is that meteors sometimes have an aerodynamic shape that can produce some kind of a “lift”. Scientists even published works on the topic, trying to solve the mystery of curved paths. One such example is M. Beech’s Non-Linear Meteor Trails work, published in Earth, Moon, and Planets Journal in 1998.
Kinked meteors start like regular meteors, i.e. with linear paths. However, they suddenly develop a kink in their trajectory but soon return to the original path. The reason why this happens is, most probably, water vapor in the atmospheric layers that have different refractive index than that of the surrounding air.
Finally, wavy meteor paths, also known as spiral paths, are similar to curved meteors.
Anomalous paths are just one example of anomalous meteor phenomena. Other phenomena include audible meteors, nebulous meteors, dark and daylight associated meteors, disk and point-source meteors, meteors with multiple trains, and finally, multiple with unusually long duration trains.
Audible meteors are one of the grand mysteries in astronomy. It is widely accepted and believed that most meteors produce sound while traveling through the atmosphere. While regular meteors are still disputed, fireballs are usually the ones to be associated with sounds. Fireballs (meteors with magnitude -4) are typically bigger than regular meteors. Reports after fireball observation often suggest hissing and rattling sound as the object was traveling through air. If you want to read more about audible meteors and fireballs, you can find interesting facts on our audible meteors page.
Nebulous meteors are meteors with fuzzy shapes and multiple bright nuclei. While most meteors that we see have had one central nucleus, nebulous meteors appear like two or more shiny cotton balls during observations. The reason behind this phenomenon is the layered disintegration. Nebulous meteors undergo multiple levels of dissolution, which is not uncommon. However, during fragmentation, most meteors break up and follow different directions. With nebulous meteors, fragments tend to stay together with minimal distances between them.
Dark and Daylight Meteors
Because the history of meteor observation is long, innumerable accounts of meteor observations exist. The nature of the field is sensitive, and before modern technology, scientists relied on amateurs. As a result, many reports were neither precise nor reliable.
While today there are almost no reports about dark meteors, at the beginning of the 20th century some scientists reported seeing dark meteors. If you are wondering what that is, well, it is exactly as we said – a dark meteor is a meteor that doesn’t shine. Thankfully, after several disputes and accounts, it was determined that the presence of a dark meteor is conditioned by the background. The one specific account stated the meteor appearance during an active Moon observation. Considering the brightness of the moon surpasses the brightness of most meteors, the object that was observed appeared to be black in color (instead of bright).
Disk and Point-Source Meteors
Disk and point-source meteors were a topic for many heated discussions in the previous century. However, the Leonid storm of 1966 convinced the astronomical community of their existence once and for all. They happen either because the meteor is heading straight towards the observer, or if most of its path is passed below the naked-eye visibility. It can suddenly light up near the end, and this is the point when the shape becomes visible to the naked eye.
Meteors with more than one tail are exceptionally rare. However, that doesn’t mean that there are no reports of such occurrences. But, despite the mystery surrounding this phenomenon, there are two logical explanations for this. First, the nucleus might split into two parts. This is very common. Due to thermal shock and pressure, the object (meteoroid) might explode and release two or more fragments. However, to produce two different trails, the fragments would have to be at a considerable distance from each other. The other explanation is potentially more plausible. Namely, some meteors release unablated materials into the air (also known as the smoke train) which observers sometimes confuse with light trains.
Long Duration Trains
Meteors last very shortly. For example, the typical duration of a meteor is 0.1 to 0.8 seconds. On the other hand, the trains behind last up to several minutes. Nevertheless, there were instances when long-duration trains were observed and reported. The explanations were hard to come by. Or, at least they were until scientists started looking into chemical compositions of meteoroids that entered the atmosphere. They discovered that different elements found in meteorites not only produce different colors, but their trains also have different duration. The main fact is that asteroidal meteors (that are composed of rocks) have better chances of leaving long and persistent trains.