Frascati, Italy: “When it comes to planetary defense, the most important is to find the Near Earth Objects early and catalogue them and this helps us design a mission if we need to mitigate them,” says Rob Landis, Operation Lead with NASA, during the 4th Planetary Defense Conference that took place on the ESRIN premises in Frascati, Italy, last week (between April 13-17).
This year, the organizers designed a simulation exercise whose purpose is to present a threat in a way that might actually evolve and make people aware of the nature of NEOs. The 250 participants, including scientists, researchers and 3 astronauts from all over the world were presented each day of the conference a new set of data and their response was requested.
The simulation was conceived by JPL NASA (NASA’s Jet Propulsion Laboratory). The application is meant to practice methods to deflect the potential asteroid assumed to hit the Earth on September 3, 2022, according to the scenario, available on the Internet:http://neo.jpl.nasa.gov/pdc15/tour.html . The app is also available on the Internet for the general public: http://neo.jpl.nasa.gov/nda/
“The most important is to complete the NEOs survey. We have to do our homework in order to absolutely understand the threat. NEO CAM and NEO WISE, the telescope spacecraft, give hope to look into the infrared, in waves that we cannot see from here from the ground, because NEOs are very dark but bright in the infrared. If we complete the survey, we need to do it in the infrared off the Earth to track NEOs. NEO WISE is not yet optimized, it was initially meant to be an astro-physics machine but it has been re-purposed and its primary focus is to search for NEOs.”
The Near-Earth Object Camera (NEOCam) was given technology development funding to mature the infrared detectors. NEOCam is meant to operate at the Earth-Sun L1 Lagrange point, allowing a large fraction of near-Earth space to be instantaneously viewable and it is close enough to Earth to support the high data rates necessary to downlink full-frame images, which are needed to extract moving objects. At the end of the NEOCam prime mission, ~75% of the potentially hazardous asteroids >140m will be discovered in 5 years. In total, the mission will increase the number of known NEOs by more than 200,000 new objects.
NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft will survey the sky at 3.4 and 4.6 microns. Operating in a terminator-following orbit, the WISE spacecraft covers the sky twice over the course of a year, with an average of ~10 exposures per region of sky for each of the two visits, so that planetary objects are often observed at several different times, over short and long time-scales, throughout their orbit.
The scientific objectives of the NEOWISE mission are to detect, track, and characterize near-Earth asteroids and comets. More than 10,000 small bodies were observed during the first year of observations, including hundreds of NEOs for which accurate diameters can be determined. Because the survey is in the infrared, NEOWISE detects asteroids based on their thermal emission.
The general public and private commercial companies should understand that “if we have a 400-metER asteroid, it’s a planetary disaster, no longer continental or regional…. People already complain about climate change…. “
Rob Landis’ suggestion is that “Companies should maybe work on infrared detectors. For the NEO WISE and NEO CAM, there were industrial partners to make the infrared sensitive detectors to find NEOs. One of the great things about launching satellites into the lower orbit was that there were no surprises, we had good tools to explore so we knew what was out there…”
Rob Landis stresses that “International cooperation and information sharing on NEOs are major. We have established the IAWN (International Asteroid Warning Network) within the UN, Dorin Dumitru Prunariu, the Romanian astronaut, was the man behind the scene and helped (N.R. Dumitru-Dorin Prunariu is the former chairman of COPUOS – the UN Committee on the Peaceful Use of Outer Space, and is now president of the European branch of the Association of Space Explorers, actively involved in UN committees in Vienna and in ESA structures in Paris). When we find out about a potential, we’ll inform the whole world in all manners very quickly, via social media, via the Internet etc…When observations of NEOs come in, they come into the Minor Planet Centre and if it is an asteroid of interest, the Sentry Program designed by the JPL does a precise determination with two separate methods, one validates and complements the other.”
Since the 2013 Planetary Defense Conference, a lot of progress has been made in finding NEO–and in international cooperation. According to the participants, a lot of missions have been designed due to the cooperation of the UN with a lot of national Space Agencies and many resources from around the world have been involved. The number of NEOs discovered every year has increased gradually, to reach 1,500 in 2014, and probably 2,000 in 2015.