IAA Planetary Defense Conference: Tokyo, Japan May 2017

Applications are now open for the IAA Planetary Defense Conference to be held in Tokyo, Japan on 15th – 19th May 2017

planetary defense conference japan 2017


What is IAA Planetary Defense Conference?

A bi-annual conference that brings together world experts to discuss the threat to Earth posed by asteroids and comets and actions that might be taken to deflect a threatening object.

What are the important Dates?

24 Sep 2016 to 14 Mar 2017
Abstract Submission Date
24 Sep 2016 to 6 Jan 2017
Paper Submission Date
15 Jan 2017 to 6 May 2017

What is special about this year’s conference?

This will be the first conference focused on planetary defense to be held in Asia!


A hypothetical asteroid impact scenario will be presented at the 2017 IAA Planetary Defense Conference (PDC), to be held in Tokyo, Japan. Although this scenario is realistic in many ways, it is completely fictional and does NOT describe an actual potential asteroid impact. The scenario is as follows:

  • An asteroid is discovered on March 6, 2017, at magnitude 21.1, and confirmed the following day. It is assigned the designation “2017 PDC” by the Minor Planet Center. (To reinforce the fact that this is not a real asteroid, we are using three letters in the designation, something that would never be done for an actual asteroid.)
  • Initial calculations indicate that 2017 PDC’s orbit approaches well within 0.05 au to that of the Earth, and it is therefore classified as a Potentially Hazardous Asteroid (PHA). (The unit “au”stands for “astronomical unit”, which is the mean distance of the Earth from the Sun, 149,597,870.7 km, or 92,955,807 miles.) The orbit is eccentric, extending from a distance of 0.88 au from the Sun at its closest point to 3.60 au at its farthest point. The asteroid’s orbital period is 1225 days (3.35 years), and its orbital plane is inclined 6.3 degrees to the orbit of the Earth.
  • The day after 2017 PDC is discovered, JPL’s Sentry impact monitoring system, along with ESA’s similar CLOMON system, both identify several future dates when this asteroid could potentially impact the Earth. The date of the most likely potential impact is July 21, 2027 – over ten years away – but the probability of impact is very low, about 1 chance in 40,000.
  • When first detected, the asteroid is about 0.36 au (54 million kilometers or 33 million miles) from Earth, approaching our planet and getting brighter. It is observed extensively, and as the observational dataset grows, the impact probability for 2027 increases. The asteroid peaks in brightness at magnitude 20.4 on April 7, by which time the impact probability has risen to nearly 0.2 percent.
  • Very little is known about the asteroid’s physical properties. Based on the apparent visual magnitude, its absolute (intrinsic) magnitude is estimated to be about H = 21.9 +/- 0.4. But since its albedo (reflectivity) is unknown, the asteroid’s mean size could be anywhere from 100 meters to over 250 meters.
  • 2017 PDC approaches the Earth for well over a month after discovery, and it reaches its closest point of about 0.13 au in late April. Unfortunately, that is too far to be detected by Goldstone radar, and too far south for Arecibo radar. The asteroid is not expected to pass close to the Earth again, until the potential impact in 2027.
  • Observers track the asteroid almost daily since discovery, and the impact probability for 2027 continues to rise. As of May 15, 2017, the probability of impact has reached about 1%. The rest of the scenario will be played out at the conference.

Where to register?

Register Here Now!


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