Though it may happen only once up to every 100 years, as estimated by the European Space Agency (ESA), the meteor airburst that generated a huge shock wave over the Russian city of Chelyabinsk last week served as an unexpected and explosive reminder of how little control humans have when it comes to our world and our universe.
Although the impact was large on a local level, injuring nearly 1,500 people and causing an estimated $33 million in damages, the impact was, as Discovery News' Ian O'Neill describes it, a cosmic flesh wound. Gone undetected, a larger body would have caused significantly more damage.
Even if there were a larger object headed toward Earth that posed a significant risk to a large number of people, and even if we could detect it, there is nothing tested and proven effective that we could deploy to mitigate that threat.
Threats from space aside, we really don't need to look beyond our planet for other reminders of how easily nature can turn against us, and there's not a whole lot we can do to push back.
Earthquakes can be violent and unpredictable, but at the same time a common reminder to anyone living along a fault line that danger lies below.
Powerful enough to move the entire planet slightly off its axis, as was the case with the 8.9-magnitude quake that triggered a tsunami that devastated Japan, earthquakes can level entire cities in a matter of minutes, as was the case with the infamous 1906 San Francisco temblor, above.
Powerful earthquakes that occur underwater can trigger massive tsunamis, a potentially devastating one-two punch for coastal areas along fault lines.
In 2004, a magnitude 9.1 earthquake that struck in the Indian Ocean caused a tsunami that killed more than 200,000 people in 14 countries, likely the deadliest tsunami in history. The amount of energy that the quake unleashed was the equivalent of more than 23,000 atomic bombs.
In 2010, a volcanic eruption in Iceland ground air traffic around Europe to a halt for weeks, causing the largest shut down of air travel since the outbreak of World War II. No one could pronounce Eyjafjallajökull, but millions of stranded travelers were surely cursing its name.
Despite the inconvenience this volcano caused, frankly the event was far from a worst-case scenario. Given that these events are violent, potentially destructive and difficult to predict, an eruption of this size could have caused more trouble had it occurred elsewhere.
Volcanic eruptions can, like earthquakes, trigger other natural disasters, including tsunamis and landslides.
Seventy percent of the Earth's surface might be covered in water. Given that so much of it isn't potable or suited to agricultural uses, and desalinating ocean water is so prohibitively expensive, drought is an age-old problem that we're still basically powerless to solve.
This year has already been a drought year in the United States, according to Secretary of Agriculture Tom Vilsack. Drought leads to higher prices for food as crops wither and rot.
If we had to pick a pony on the "Is zero a number?" debate, we'd have to go with the side that asserts it is. Just ask anyone who's gone hungry without any food during a famine: having nothing definitely feels like something.
Be it caused by drought, pestilence or some other root cause of crop failure, famine is a disaster in slow motion that can lead to malnutrition, widespread disease and death by starvation.
At its most basic level, putting out a fire seems simple enough: Just add water.
A fire that spreads to the point where a fire extinguisher or a hose has no effect, however, is a different matter all together.
Firefighers battling wildfires last year were kept more than busy. In the first six months of the year alone, half a million acres burned in the United States, according to Discovery News' Tim Wall. By November, that number skyrocketed to over 9 million acres, or equal to the size of Massachusetts and Connecticut combined.
Last year was the third time in history that the United States hit the 9-million-acre mark for wildfires. The last two times it happened were in 2006, when 9.8 million acres burned, and 2007, when 9.3 million acres went up in smoke, according to USA Today.
With global climate change exacerbating the issue, not only in the United States, but also wildfire-prone nations like Australia, wildfires will only get bigger.
Triggered by heavy rains and extreme storms, floods can cause lasting damage unlike few other natural disasters. Not only do floods claim immediate losses in terms of lives and property, but prolonged flooding can encourage the spread of disease, overwhelm crops and trigger further disasters, like mudslides.
It's no surprise then why in the Old Testament, out of all the natural disasters at God's disposal, He chooses floods to wipe out the Earth. The deadliest flood in recorded history, however, occurred in China in 1931, in a series of catastrophes that claimed upwards of 4 million lives, according to some estimates.
Despite the fact that your chances of getting struck by lightning are only slightly better than your chances of winning the lottery, lightning is still a powerful natural force that manages to instill a kind of simultaneous primal fear and curiosity to anyone near it.
Lightning strikes the Earth's surface about 100 times every second, generating up to one billion volts of electricity with each strike.
Sending walls of snow down mountains and hills, avalanches can be deadly and destructive.
During World War I, some 60,000 Italian and Austrian troops died fighting in the Alps as a result of avalanches, according to National Geographic. In fact, 10,000 troops were killed in a single day on Dec. 13, 1916.
Thankfully, avalanches, when not triggered themselves by unpredictable events like earthquakes, can be occasionally predicted and mitigated with controlled blasts in vulnerable areas.
Landslides are the rocky cousin to avalanches and can be just as damaging. Landslides can occur naturally in the wake of a volcanic eruption or an earthquake, for example. But humans can exacerbate the problem, as was suggested in the wake of the 2010 landslide in Gansu province in China, which claimed 1,471 lives with nearly 300 people still missing two and a half years later.
A mudslide might sound like a fun activity you might try if you're a kid at summer camp. To a jaded adult turned barfly, a mudslide is a drink. A mudslide in geological terms is exactly like neither one of those things.
A stream of loose soil, water and anything floating on top, a mudslide is a type of landslide, except mudslides are characterized by faster-moving flows of debris, according to the Centers for Disease Control and Prevention. They can be triggered by heavy precipitation or volcanic eruptions, and cause significant damage.
No matter what you call it -- a hurricane or a typhoon, whether it's in the Atlantic or the Pacific -- these powerful storms can cost lives and reap billions of dollars of damage when they hit vulnerable coastlines.
Although meteorogolists are increasingly adept at predicting these massive cyclones with each passing season, knowing a hurricane's projected path doesn't mean a whole lot if preparations aren't in place to cope with the aftermath after it strikes land.
Hurricane Katrina is undoubtedly the most powerful and costly example of this kind of storm, costing more than $100 billion in damage, killing more than 1,800 people and nearly wiping an entire American city off the map.
Despite their size relative to hurricanes, tornadoes can cause enormous damage and come with little advance warning before they touch down. Although tornado numbers seem to be going up over the decades, that has to do more with the efficiency of reporting these events, as Joshua Wurman, president of the Center for Severe Weather Research, told Discovery News' Robert Lamb.
Furthermore, despite the damage they can and do still cause, the number of fatalities following major tornadoes has gone down in the United States since the middle of the 20th century, owing to better preparedness and emergency management.
Given that most of the United States is at the point of the season when they're tired of the winter weather, a heat wave might sound like a welcome respite from the cold. But of course, if you live in the Northern Hemisphere and forget how devastating a heat wave can be, phone a friend in Australia and ask how they're doing.
Heat waves, increasingly common and severe as a result of the impact of climate change, can be deadly for those not adequately hydrated or sheltered from the weather, and costly for everyone else. Hot, dry conditions can also spark wildfires and drought, turning discomfort into disaster in short order.
Remember a time when cold weather storms didn't have names like "Snowmageddon" and "Snowpocalypse"? Pepperidge Farm remembers.
Snow storms of historic and abnormally intense proportions have grown increasingly common of late. How much these storms can be attributed to climate change is up for debate, but increasingly Americans are convinced that a shifting global climate is underway and responsible for these events, according to a recently released Duke University poll.
Not every potential disaster is large and visibly menacing. A pandemic, be it a virus, bacteria or some other form, would be invisible, far-reaching and potentially deadly.
HIV, smallpox, tuberculosis and influenza are among a handful of diseases that have devastated human populations over the centuries, each responsible for millions of deaths.
Although there's no way to anticipate future diseases, the good news is that we're increasingly getting better at coping with the ones we know about. Smallpox has been eradicated. Tuberculosis can be treated with antibiotics, though new strains of drug-resistant TB do exist. HIV, though a disease still affecting millions, isn't the same lethal agent it was once, thanks to the successful administration of drug combinations, or cocktails, to affected patients.
In one fell swoop, a solar flare could take out our satellite systems and our power grid, bringing our entire modern way of life to a halt.
Solar flares can't be predicted, but there are periods in which the sun is more dormant, the solar minimum, and others when it is more active, the solar maximum, in its 11-year cycle.
If we do ever have to cope with the possibility of a blast of energy equivalent to 100 billion Hiroshima-sized atomic bombs, there's little we can do except hope Earth's magnetic field is protection enough to weather the storm.
The result of a massive star explosion when it goes supernova, gamma-ray bursts are so powerful that they can be detected on the other side of the universe. These explosions release a mind-boggling amount of energy, equivalent to 167.3 megatons of TNT.
Evidence of a gamma-ray burst explosion has been detected from fossil evidence dating to the 8th century. No major bursts have headed our way in modern history.
Like solar flares, gamma-ray bursts could cause extensive damage to our satellites and electrical technology.
If there's one thing in the universe which you could not possibly hope to survive should you encounter it, a black hole should be it.
Yes, the closest black hole discovered to date is some 1,500 light-years away. But remember: Before the Large Hadron Collider fired up and went fully operational in 2009, some scientists and mathematicians expressed concern that the particle collider would cause a black hole that could swallow the globe.
That, of course, hasn't happened -- not yet, anyway.