Apophis was an ancient Egyptian spirit – an evil entity that threatened the sun god Ra during Ra’s travels through the underworld.
Such an entity of death seems to be the perfect name for the asteroid that poses the most serious threat to the earth. This massive asteroid – the 99942 Apophis – measures an astonishing 1,066 feet (325 meters) wide, according to estimates of European Space Agency astronomers in January of 2013.
In fact, it was on January 9th of 2013 that the asteroid – once labeled as the asteroid most likely to strike Earth – made a very close shave. It came within 9 million miles of Earth.
However, subsequent passes in 2029 and 2036 bring the monster asteroid far closer to earth – a surprisingly close 20,000 miles.
Only a month later in February, the Asteroid 2012 DA14 missed earth by only 17,100 miles above the planet.
It was the closest pass of any known asteroid since astronomers started surveying the objects in the 1990s. These near misses have many people wondering not if one of these massive rocks will ever collide with earth, but when.
How Long Are We Safe?
Scientists have downgraded the likelihood of 99942 Apophis striking earth. NASA experts reported humans can “effectively rule out an Earth impact in 2036.” (2)
This is great news to anyone that may be fearful of a disastrous asteroid impact within the next couple of decades, but anyone alive today who’s under 40 years of age will live to see whatever happens well through 2060.
Children of today will see any events that occur straight through to 2100. However, what if astronomers have their calculations slightly wrong – if not for the 2029 pass, then for the 2036 pass?
And if not then, what threats remain over the three or four decades afterwards? How long before the human race runs out of luck – and what will that impact event look like?
The Odds of an Impact
As a general rule, scientists don’t want to generate fear, so mostly what you’ll hear is that the odds are very, very distant of an impact any time in the near future.
At the risk of being labeled as a “scaremonger” by those scientists, I’d like to explore any imminent risks.
The NASA Near Earth Object Program indicates 13 recently observed objects that represent a potential future earth impact event. The 1013 BP73 with 9 potential impact events between 2078-2107, the 99942 Apophis with 19 potential impact events between 2036-2105, and the 2013 BR27 with an impressive 51 potential impact events between 2073-2110. (5)
The good news is that of the Near Earth Asteroids greater than 1km in diameter, none are a threat to the planet earth. The bad news is that astronomers have not necessarily spotted all threats – and there is always the possibility of impact from an “unknown object”.
Furthermore, even smaller objects – such as the meteor that recently exploded in the skies over the Ural Mountains in Russia – can clearly cause a certain degree of damage and destruction, even if not a cataclysmic earth-changing event. The Russian meteor was only 55 feet in diameter. Future objects could be much larger, and will also be undetectable until they strike earth.
What Would Impact Look Like?
In February of 2013, Time Magazine ran through a realistic scenario of a 330-foot (100m) asteroid on a collision course for New York City.
In the scenario, astronomers noticed the object at least eight months away, providing residents with eight months to fully evacuate the city. The 8.3 million people would scramble to permanently vacate the city – in full knowledge that after the event, there would be no city left.
If compared to the estimated 100-meter asteroid that scientists believe exploded over Tunguska River in Central Russia in 1908, the massive blast over New York City would produce an explosion of 30 megatons (1,000 Hiroshima nuclear blasts). (6)
In a New York scenario, the blast with a radius of 14.4 miles would take out most of Queens, Staten Island, the Bronx, Brooklyn and surrounding areas – the areas would be “swallowed whole”.
6.5 miles from the epicenter, only foundations would remain. 11 miles out, homes would be stripped to the frames or completely destroyed.
Scientists work hard to set the public’s mind at ease by listing off statistical odds that make winning the lottery more likely than earth getting hit by an asteroid. However – people do win the lottery. And as Jeffrey Kluger of Time Magazine wrote, “all it takes is one.”
References & Image Credits:
(2) Sydney Observatory
(3) Daily Mail
(4) Discovery News
(5) NASA Near Earth Object Program
(6) Time Magazine
(7) Lights In The Dark via photopin cc
(8) homer4k via photopin cc
(9) alexeya via photopin cc