Private-Sector Space Race: After America Landed Men on the Moon, the Space Race between Russia and the United States Stalled. Now Entrepreneurs Are Enthusiastically Investing in Space Exploration
Scaliger, Charles, The New American
On February 15, at about 9:20 a.m. local time, residents of the city of Chelyabinsk in the southern Ural region of Russia were startled at the appearance of a blazing light in the southeastern sky. At first, the mysterious object appeared to be either a brilliant meteorite or a manmade missile, but as the seconds passed, the fireball grew brighter and brighter, until it outshone the sun. Finally, the object exploded with a flash resembling that of a nuclear bomb, with several less luminous objects continuing across the sky in the explosion's wake. As astonished Russians gazed skyward, filming the thick gray contrail left by the object, Chelyabinsk was slammed by a powerful shock wave--captured by a number of video cameras and cellphones--that blew out the windows in thousands of buildings, raining broken glass on terrified pedestrians. Over 1,500 people were hospitalized, mostly from glass cuts. The roof of a zinc factory collapsed from the concussion. One dramatic video showed a couple of office workers enjoying a morning conference when the shock wave hit, blowing in the window and hurling both of them across the room.
Many Russians in the region were understandably terrified by the event, and assumed at first that their homeland was under missile attack. But within minutes, the truth of what had happened over Chelyabinsk was racing around the world: For the first time in over 100 years, planet Earth had suffered an asteroid strike.
The last time anything like the Chelyabinsk event took place was on June 30, 1908, in the area of the Tunguska River in eastern Siberia. That morning, residents of the then (and still) sparsely inhabited region reported seeing a gigantic light speed across the heavens, followed by an explosion so powerful that people were thrown through the air and huts were damaged or destroyed. Eyewitness accounts from villages as far as 40 or 50 miles from the epicenter reported massive damage from powerful winds and fire. The explosion was so bright that it was seen (and heard) thousands of miles away; across Asia and even as far as Europe, the night skies glowed with an eerie light for several days after the event.
Because of the remoteness of the area and the turmoil of the First World War and the Russian Revolution, not until 1921 did a team of scientists reach the site of the Tunguska event, braving hundreds of miles of trackless taiga and mosquitoes. What they found was shocking. An area covering some 830 square miles had been blasted by some kind of extraordinary explosion that had converted dense boreal forest into a virtual moonscape of charred tree trunks. For many miles in every direction from the epicenter, trees had been blown flat and burned to a crisp. Because the 1921 expedition and many subsequent efforts found no crater, it was concluded that the object--whatever it was--had exploded before hitting the ground.
The exact identity of the Tunguska object remains uncertain, although it was almost certainly either a cometary body or an asteroid measuring more than 300 feet across. The explosion occurred over the Siberian wilderness and--as far as anyone knows--claimed no lives, but it remains an object of enduring interest for astronomers. Given the extent of the devastation, it is clear that, had the event occurred over densely populated Western Europe, southern Asia, or the northeastern seaboard of the United States, thousands or even millions of casualties might have been the result.
Nowadays, concern over the possibility of an asteroid strike on the Earth has been driven not only by the memory of the Tunguska event but also by the growing scientific recognition that such events have taken place many times during Earth's history, sometimes resulting in extinction-level devastation, as with the six-mile-wide space rock that struck near Chixculub in what is now the Yucatan Peninsula and apparently triggered the demise of the dinosaurs. …