6th Extinction
The internet has become a better place since Russians started uploading footage from their dashcams.
Originally deployed for protection against the Russian Highway Patrol (GAI) and insurance scams and hit-and-run accidents, Russian dashcam footage has become an internet meme in its own right. The footage ranges from the sublime to the ridiculous: a man blissfully pushes himself from one side of a four-lane highway to the other in a shopping cart; cows emerge placidly from an overturned truck, and an SUV bursts into flames after a particularly damning lightning strike. Of all these poignant moments, none is as striking as the 2013 meteor event that took place over Chelyabinsk, a small city in Siberia. Recorded by hundreds of dashcams, the meteor is the largest object to have passed through our atmosphere since the Tunguska event (also in Russia) in 1908. The footage shows the meteor arcing through the sky and reaching the earth with a spectacular display, predictably the largest reported fireball since Tunguska. The impact was registered by stations designed to detect nuclear blasts and picked up on seismic records over 4000 kilometers away from the impact site, a frozen lake.
According to NASA, the fireball burned thirty times brighter than the sun, causing at least 20 people to suffer from severe sunburns and flash blindness, though most harm to people resulted from shattered glass due to the sonic boom the meteor created.
Closer to home, South Africa experienced a very bright meteor on November 21, 2009. Seen as far north as Zimbabwe and as far east as Swaziland, the meteorite is thought to have landed somewhere in Botswana. The footage we have from Johannesburg traffic cameras shows a flash of light that turned night into day for a fleeting moment. Eyewitnesses saw a fireball of bluish-green light followed by an orange flash, and according to some reports, people ran out of their houses with guns, thinking the country was under attack.
Meteors, more commonly known as ‘shooting stars,’ are fragments of space rock that ignite from the friction caused by their speed as they enter Earth’s atmosphere. They are called meteorites once they hit the ground, though most meteors burn up before impact. Mostly, the shooting stars we see are caused by particles as small as specks of dust, but occasionally, we encounter larger ones.
After unexpected events such as the Chelyabinsk impact, there are calls for better documentation of Near-Earth Objects (NEOs) and some kind of global strategy for dealing with them. What this strategy would be, though, no one knows. There is a United Nations Committee on the Peaceful Uses of Outer Space that meets annually to discuss novel ways to address threatening asteroids, but the general view is that by the time we detect one on a collision course with Earth, it will likely be too late to take action. The fact that we've discovered they pass closer and more frequently than previously thought may be due to more powerful telescopes, but simply spotting them won't necessarily aid our survival should one pose a threat.
Asteroids are responsible for at least one of the five major extinction events, notably the event that killed the dinosaurs and left a 180km-wide crater in Mexico’s Yucatan Peninsula. Known as the K-T extinction event, it is estimated that around three-quarters of life on Earth perished, either directly from the impact or from the ‘impact winter’ that followed, as particles ejected into the atmosphere disrupted the basic life process of photosynthesis. Sunlight would have been obscured for months, forcing surviving animals to subsist on detritus-based food chains. Even after the skies cleared, the additional greenhouse gases in the atmosphere caused an increase in Earth’s temperature, making life exceedingly uncomfortable.
The K-T extinction was global, severe, and swift. At the current rate of human-caused extinction of plant and animal life, we are facing another mass extinction event, often referred to as the ‘sixth extinction.’ To us, this may seem like a gradual decline, nothing comparable to the dramatics of the K-T extinction. However, on a geological scale, the current rate of extinction is indeed global, severe, and swift. The rate of extinction is at a crisis level, estimated to be between 1,000 to 10,000 times higher than the natural extinction rate, and even more rapid for certain species such as amphibians and corals.
Only 850 species have been formally documented as ‘extinct,’ though the actual rate is believed to be higher, with many species critically endangered and numerous others facing imminent demise. On a windy hill on the British Isle of Portland, a monument is being built to commemorate these losses. Its central feature will be a ‘great geological bell,’ tolled each time a species goes extinct. The project is planned by the Mass Extinction Monitoring Observatory and aims to underscore the significance and magnitude of the challenges biodiversity faces.
As industrial production continues to accelerate, it's likely that it won't be a 4.4 billion-year-old asteroid that extinguishes life, but rather ourselves. Thus, the bell at Portland may soon require a full-time bell-ringer. Given that carbon emissions drive much of the global warming process, it seems fitting that on our highways, fleeting moments of flaming meteor beauty are also recorded as well-placed memento mori.
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