The survival of the human race is a serious matter. The United Nations recently drafted a <a href="http://daccess-dds-ny.un.org/doc/UNDOC/GEN/N13/472/83/PDF/N1347283.pdf?OpenElement">resolution</a> that recommends including the creation of an International Asteroid Warning Group to help protect society from Near Earth Objects. The resolution will most likely be adopted. Though a small step for the UN, this could be a large move for humanity. It is laudable and further technical and political measures should be considered.
Early this year, a meteor exploded above Chelyabinsk, Russia <a href="http://www.reuters.com/article/2013/02/15/us-russia-meteorite-idUSBRE91E05Z20130215">injuring 1,000 people</a> due to the resulting shock wave. The warning systems we have in place did not detect the asteroid. Luckily, there were no deaths but these rare events have become a wake up call for professional and amateur astronomers.
The threat posed by Near Earth Objects (NEO) is real. An asteroid detected in 1997, <a href="http://en.wikipedia.org/wiki/(35396)_1997_XF11">1997XF11</a>, will bypass Earth in 2028 but would likely wipe out life on the planet if it collided with Earth’s atmosphere. It is estimated that there are roughly one million asteroids within the Sun’s orbit, <a href="http://neo.jpl.nasa.gov/stats/">10,000</a> of which are being tracked by NASA. Small asteroids collide with the planet regularly. Most burn up in the atmosphere. The few that make it through vary in size, composition, and angle of entrance. Early warning systems are the best approach to prepare for a collision, thus enabling time to deflect the object or evacuate the impact zone. For instance, <a href="http://www.telegraph.co.uk/science/space/10413205/United-Nations-to-lead-efforts-to-defend-Earth-from-asteroids.html">under the new plan</a> the “UN Committee on the Peaceful Uses of Outer Space will monitor detections and help plan a deflection campaign if that is necessary.”
The realization and acceptance by scientists of the inevitability of a collision with Earth is not new. The probability of another asteroid striking Earth is 100%; there is no uncertainty in this calculation. The uncertainty exists in determining <i>when</i> such a significant collision will occur. The product of the probability of collision in any given year and the effect on society of the collision is a calculation fraught with high degrees of uncertainty because it depends on many parameters: diameter, composition, density, velocity, and angle of impact of the asteroid, as well as the timing, population density at the location of impact, and local infrastructure of society.
Despite this difficulty, it is widely accepted in scientific communities today that the risk of doing nothing is unacceptable. The cost-benefit analysis, though noisy, is clearly in favor of protecting human life. It begs the question: Do we ensure the survival of future generations by making investments now? And the more difficult question: If so, how many resources should be devoted to these endeavors?
Today we have advanced technologies to sense, collect, store, analyze, and predict these projectiles on massive scales. For example, RF and laser radar technology, big data analytics, modeling and simulation software, commercial launch capabilities, and autonomous systems have advanced rapidly in recent years. This past June NASA launched a <a href="http://www.nasa.gov/mission_pages/asteroids/initiative/index.html">grand challenge</a> to gather ideas to mitigate the threat of asteroids, including bold ideas such as solar sails and gravity tractors.
Communicating the science of asteroid physics is also critical to enable policy implementation. Hollywood movies like Armageddon might be entertaining, but in the end they do little to educate the public due to the fact that they come from fiction-based Hollywood and are bursting with technology flaws. Rational, vetted analysis based on rigorous scientific research presented in widely understandable language is the only way to make political headway.
The international support to plan for space rock collision is promising. Private space companies, groups such as the Association of Space Explorers, B612 Foundation, The Lifeboat Foundation, international organizations, and government agencies should partner to confront this task together. With greater collaboration, testing, information sharing, and mock impact scenarios in place we can ensure that we are dedicating resources to a worthy cause.
The ability to predict rare events such as an asteroid collision is achievable and our human ingenuity will ensure this. In order for our government to fulfill its responsibility to protect its citizens, more federally sponsored research needs to be conducted on asteroid collision mitigating science and technologies. Surely, it is a worthy endeavor of human activity to protect the human race and ensure its longevity. Given that the world spends roughly <a href="http://books.sipri.org/product_info?c_product_id=458">$1.75 trillion</a> annually defending ourselves against one another, wouldn’t it be wise to spend a few billion a year to defend ourselves from true external, existential, space-based threats.