Potentially Hazardous Asteroids Identified by NASA Scientests

NASA officials have reported the recent results of observations from its Wide-field Infrared Survey Explorer (WISE) which have identified and completed a count of asteroids which could pose a real threat to the Earth.

Like something from the film ‘Armageddon,’ potentially hazardous asteroids (PHA) are part of a large group of asteroids referred to as near-Earth asteroids. What is different about the PHAs is their potential danger to life here on earth due to their closer orbit to Earth. The asteroids considered to be a threat are those with orbits which pass within five million miles and are big enough to still be of substantial size after burning through the Earth’s atmosphere.

According to NASA, “The project sampled 107 PHAs to make predictions about the entire population as a whole. Findings indicate there are roughly 4,700 PHAs, plus or minus 1,500, with diameters larger than 330 feet (about 100 meters). So far, an estimated 20 to 30 percent of these objects have been found.”

“The NEOWISE analysis shows us we’ve made a good start at finding those objects that truly represent an impact hazard to Earth,” said Lindley Johnson, program executive for the Near-Earth Object Observation Program at NASA Headquarters in Washington. “But we’ve many more to find, and it will take a concerted effort during the next couple of decades to find all of them that could do serious damage or be a mission destination in the future.”

The news isn’t all bad however. Firstly, there are currently no asteroids which are currently on any type of collision course with the Earth, or pose an immediate or near term threat to the planet. Also, some of the asteroids on what is termed a lower-inclination orbit would be more likely to encounter Earth and would be easier to reach for potential future robotic or human missions and commercial mining operations.

“NASA’s NEOWISE project, which wasn’t originally planned as part of WISE, has turned out to be a huge bonus,” said Amy Mainzer, NEOWISE principal investigator, at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Everything we can learn about these objects helps us understand their origins and fate. Our team was surprised to find the overabundance of low-inclination PHAs. Because they will tend to make more close approaches to Earth, these targets can provide the best opportunities for the next generation of human and robotic exploration.”