International coordination on planetary defence: The work of the IAWN and the SMPAG

Space capabilities play a crucial role in ensuring human security. One of the threats coming from space is the possible damage to our assets by an asteroid or comet impact. As demonstrated by the object entering the Earth's atmosphere over Chelyabinsk, Russia, in February 2013, the threat of an asteroid or comet impact is a real and global issue demanding development of an international response. Addressing such a hazard, by first identifying those objects that pose a threat to enable planning a corresponding mitigation campaign, require international coordination. The United Nations Member States, especially those with capabilities to engage in a possible planetary defence mission, already share a number of common activities in this field. This paper outlines the progress made in the implementation of recommendations for an international response to the NEO impact threat, as agreed under the auspices of the United Nations (UN) Committee on the Peaceful Uses of Outer Space (COPUOS) and welcomed by the UN General Assembly in its resolution 68/75 of December 2013. The recommendations provide for a coordinated international response to a possible NEO threat. They aim at ensuring international information-sharing in discovering, monitoring and physically characterizing potentially hazardous NEOs with a view that all countries, in particular developing countries with limited capacity in predicting and mitigating a NEO impact, are aware of potential threats. They emphasize the need for an effective emergency response and disaster management in the event of a discovered NEO impact threat. The International Asteroid Warning Network (IAWN) and the Space Mission Planning Advisory Group (SMPAG), which are the two entities established in 2014 as a result of the UN-endorsed recommendations, are important mechanisms at the global level for strengthening the coordination in the area of planetary defence. The United Nations Office for Outer Space Affairs (UNOOSA) acts as secretariat to SMPAG and works with both IAWN and SMPAG in addressing this global issue. In the event of a credible impact prediction, warnings would be issued by the IAWN, the SMPAG would propose mitigation options and implementation plans for consideration to the Member States. The goal is the global protection of the eco-system, of human beings and their properties on Earth, and of the civilization of humankind from a devastating asteroid impact. The current paper outlines the work of the IAWN and the SMPAG towards a road-map for planetary defence at the global level, including agreements on initial criteria and thresholds for impact threat response actions, consideration of mitigation mission types and technologies and mapping of threat scenarios to mission types as well as developing a plan for action in case a credible threat is discovered. The paper also reflects on how to convey information about the NEO impact warnings and associated impact probabilities to the public and governmental decision-makers as part of the agreed communications guidelines, which are another important pillar in the work of the IAWN.