Fifth interagency planetary defense tabletop exercise focused on an asteroid impact scenario projected by NASA’s JPL Center for Near-Earth Object Studies.
A large asteroid hitting Earth is unlikely for the foreseeable future. But because the damage from such an event could be great, NASA conducts hypothetical asteroid impact “tabletop” exercises every two years with experts and decision makers from federal and international agencies to address the many uncertainties of an impact scenario. . The most recent exercise took place last April, with a preliminary report released on June 20.
Making such a scenario realistic and beneficial to all involved is no small task. Scientists from the Center for Near-Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory in Southern California, which specializes in tracking and determining the orbits of asteroids and comets and detecting whether any of them are dangerous to Earth, have played a major role in designing these exercises from scratch 11 years ago.
“These hypothetical scenarios are complex and require significant effort to design, so our goal is to make them useful and challenging for exercise participants and decision makers to improve their processes and procedures to quickly arrive at an action plan addressing the gaps in the defense community’s knowledge,” said Paul Chodas of JPL, director of CNEOS.
This year’s scenario: A hypothetical asteroid has been discovered, perhaps a few hundred yards across, with an estimated 72% chance of hitting Earth in 14 years. Potential impact sites include heavily populated areas in North America, southern Europe and North Africa, but there is still a 28% chance the asteroid will miss Earth. After several months of tracking, the asteroid moves too close to the Sun, making further observations impossible for another seven months. Decision makers need to understand what to do.
The exercise was led by NASA’s Planetary Defense Coordination Office (PDCO), the Federal Emergency Management Agency’s Response Directorate and the State Department’s Office of Space Affairs. Over two days in April, participants gathered at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, which hosted the event, to consider possible national and global responses to the scenario.
“This was a very successful tabletop exercise, with nearly 100 participants from US government agencies and, for the first time, international planetary defense experts,” said APL’s Terik Daly, who coordinated the exercise. “An asteroid impact would have severe national and international consequences, so if this scenario actually occurs, we will need international cooperation.”
In real life, CNEOS calculates the orbit of every known near-Earth object to provide estimates of potential future impact hazards in support of NASA’s planetary defense program. To make this scenario realistic, the CNEOS team simulated all observations in the months leading up to the exercise and used orbit determination calculations to simulate the impact probability.
“At this point in time, the impact was possible but not yet certain, and there was considerable uncertainty in the size of the object and the location of the impact,” said Davide Farnocchia, a navigation engineer at JPL and CNEOS, who led the design of the asteroid. the orbit. “It was interesting to see how this affected the choices of decision-makers and how the international community could respond to a real-world threat 14 years later.”
Preparation, planning and decision-making have been the main focal points of all five exercises that have been conducted over the past 11 years. For example, could a reconnaissance spacecraft be sent to the asteroid to gather additional data on its orbit and better determine its size and mass? Would it also be possible to try to deflect the asteroid so that it misses Earth? The applicability of this method was recently demonstrated by NASA’s Double Asteroid Redirection Test (DART), which impacted the asteroid moon Dimorphos on September 26, 2022, slightly altering its trajectory. Other diversion methods were also considered during the exercises.
But any diversion or detection mission would require many years of preparation, requiring the use of advanced observatories capable of finding dangerous asteroids as quickly as possible. NASA’s Near-Earth Object Observatory, or NEO Surveyor, is one such observatory. Managed by JPL and scheduled for launch in late 2027, the infrared space telescope will detect light and dark asteroids, including those orbiting close to the Sun. In doing so, NEO Surveyor will support PDCO’s objectives to detect any hazardous asteroids as quickly as possible, so that there is more time to launch a diversion mission to potential threats.
To find out the result of the exercise, read NASA’s preliminary summary.
For more information about CNEOS, visit:
https://cneos.jpl.nasa.gov/
Ian J. O’Neill
Jet Propulsion Laboratory, Pasadena, California.
818-354-2649
ian.j.oneill@jpl.nasa.gov
Karen Fox / Charles Blue
NASA headquarters
202-358-1600 / 202-802-5345
karen.c.fox@nasa.gov / charles.e.blue@nasa.gov
2024-095