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In 2001, a rag-tag group of countries and organizations got together to form a crack NEO Action Team.
Mandated to "Improve the international coordination of activities relatedto near-Earth objects"1,
The A-Team 14 writes papers and has discussions and dreams one day
of some sort of implementation of a Asteroid Mitigation theory.2
1. The Action Team on Near-Earth Objects was established in response to
recommendation 14 of the Third United Nations Conference on the Exploration and
Peaceful Uses of Outer Space (UNISPACE III) and was given the following terms
of reference:
(a) Review the content, structure and organization of ongoing efforts in the
field of near-Earth objects (NEOs);
(b) Identify any gaps in the ongoing work where additional coordination is
required and/or where other countries or organizations could make contributions;
(c) Propose steps for the improvement of international coordination in
collaboration with specialized bodies.
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19 Countries:
– Australia, Brazil, China, Czech Republic, Finland,
Germany, Iran, Japan, Kazakhstan, Lebanon,
Malaysia, Nigeria, Pakistan, Poland, Russian
Federation, Saudi Arabia, Syrian Arab Republic,
United Kingdom, United States of America
9 Organisations:
– Association of Space Explorers (ASE), European
Space Agency (ESA), Committee of Space Research
(COSPAR), International Astronomical Union (IAU),
National Space Society, Space Generation Advisory
Council, European Space Science Committee,
European Science Foundation, SpaceGuard
Foundation
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| Action Team 14 Work Plan
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2009
– Continue annual reporting on NEO activities and inter-sessional
work in preparation for the 2009 theme which will include an
update on NEO missions and draft procedures related to threat
handling at the international level
– Review and update Interim Report
• 2010
– Continue with drafting (or agree) international procedures for
threat handling and review progress with international
cooperation and collaboration on observations
– Review and update Interim Report
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"IX. Near-Earth objects
136. In accordance with General Assembly resolution 63/90, the Scientific and
Technical Subcommittee considered agenda item 11, “Near-Earth objects”, under
the amended multi-year workplan adopted by the Subcommittee at its fortyfifth
session (A/AC.105/911, annex III). Pursuant to the workplan, in 2008,
international organizations, regional bodies and others active in the field of near-
Earth object research were invited to report to the Subcommittee on their activities.
137. The representatives of Austria, Canada, France, Japan, Mexico, Poland,
Romania, the Russian Federation and the United States made statements on the
item.
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138. The Subcommittee heard the following scientific and technical presentations:
(a) “Asteroid-comet impact hazard problem: recent developments in
Russia”, by the representative of the Russian Federation;
(b) “Near-Earth object observation program”, by the representative of the
United States;
(c) “NEOSSat: the near-Earth objects surveillance satellite”, by the
representative of Canada;
(d) “French activities related to Apophis”, by the representative of France;
(e) “The Large Millimeter Telescope”, by the representative of Mexico;
(f) “Dealing with the threat to Earth from asteroids and comets”, by the
observer for IAA;
(g) “Asteroid threats: a call for a global response”, by the observer for the
Association of Space Explorers (ASE);
(h) “Assessment of the proposal, by the Association of Space Explorers
International Panel on Asteroid Threat Mitigation, on the theme ‘Asteroid threats: a
call for a global response’”, by the observer for IAF.
139. The Subcommittee had before it the following documents:
(a) Note by the Secretariat on information on research in the field of near-
Earth objects carried out by Member States, international organizations and other
entities (A/AC.105/926);
(b) Interim report of the Action Team on Near-Earth Objects (2008-2009)
(A/AC.105/C.1/L.298).
140. The Subcommittee noted that near-Earth objects were asteroids and comets
with orbits that could cross the orbit of planet Earth. The Subcommittee also noted
that the interest in asteroids was largely fuelled by their scientific value as remnant
debris from the inner solar system formation process, the potentially devastating
consequences of such objects colliding with Earth and the possession of a wide
range of natural resources.
141. The Subcommittee noted that early detection and precision tracking were the
most effective tools for the management of threats posed by near-Earth objects. In
that regard, the Subcommittee noted with satisfaction that a number of international
teams in various countries were currently searching for, investigating and
cataloguing near-Earth objects and that new partnerships were emerging among
national space agencies and research institutions to enhance those efforts.
142. The Subcommittee noted with satisfaction that a number of institutions were
investigating possibilities for mitigating the threats posed by near-Earth objects. The
Subcommittee also noted that any measures to mitigate such threats would require
coordinated international efforts, as well as increased knowledge of the properties of
near-Earth objects.
143. The Subcommittee noted with satisfaction that the ASE International Panel on
Asteroid Threat Mitigation had prepared a report on the theme “Asteroid threats: a
call for a global response”.
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144. The Subcommittee noted that some member States had implemented or were
planning to implement fly-by and exploration missions to near-Earth objects. The
Subcommittee also noted past and upcoming missions investigating near-Earth
objects, including: the Dawn, the Deep Impact and the Stardust spacecraft of the
United States; the Near Earth Object Surveillance Satellite of Canada; and the
Marco Polo near-Earth object sample return mission of ESA; and the Hayabusa
near-Earth object sample return mission of Japan. The Subcommittee also noted that
a number of international projects and initiatives, such as the Panoramic Survey
Telescope and Rapid Response System (Pan-STARRS), the Large Millimeter
Telescope, the Large Synoptic Survey Telescope and the Pulkovskaya Observatory,
took advantage of potential dual-use facilities to advance detection and
characterization capabilities.
145. The Subcommittee noted the significant progress achieved by the United
States in reaching its target of detecting 90 per cent of all near-Earth objects greater
than one kilometre in diameter. The Subcommittee noted that the United States had
determined that fewer than 150 of the 825 near-Earth objects with a diameter greater
than one kilometre could pose a collision hazard with Earth. The Subcommittee
further noted that the United States was seeking to achieve, by 2020, its target of
detecting, tracking, cataloguing and characterizing 90 per cent of objects with a
diameter greater than 140 metres.
146. The Subcommittee agreed that efforts to detect, track and characterize near-
Earth objects should be continued and expanded at the national and international
levels.
147. Pursuant to paragraph 15 of General Assembly resolution 63/90, the
Subcommittee, at its 709th meeting, on 16 February, reconvened its Working Group
on Near-Earth Objects under the chairmanship of Richard Crowther (United
Kingdom). The Working Group on Near-Earth Objects held four meetings.
148. At its 716th meeting, on 20 February, the Subcommittee endorsed the report of
the Working Group on Near-Earth Objects (see annex III)."
"Annex III
Report of the Working Group on Near-Earth Objects
1. Pursuant to paragraph 15 of General Assembly resolution 63/90, the Scientific
and Technical Subcommittee, at its forty-sixth session, reconvened its Working
Group on Near-Earth Objects. The Working Group held three meetings, from 16 to
18 February 2009, under the leadership of the Chairman, Richard Crowther (United
Kingdom of Great Britain and Northern Ireland), and one meeting on 20 February
2009, under the leadership of the Acting Chairperson, Creena Lavery (United
Kingdom).
2. In accordance with the multi-year workplan under the item on near-Earth
objects (NEOs) (A/AC.105/911, annex III), the Working Group considered:
(a) Reports submitted in response to the annual request for information on
NEO activities and intersessional work;
(b) Review of policies and procedures related to the handling of the NEO
threat at the international level and drafting of international procedures for handling
the NEO threat;
(c) Activities undertaken within the framework of the International Year of
Astronomy 2009 to raise awareness of the NEO threat;
(d) The updated interim report of the Action Team on Near-Earth Objects
(2008-2009) (A/AC.105/C.1/L.298).
3. The Working Group had before it a note by the Secretariat on information on
research in the field of near-Earth objects carried out by Member States,
international organizations and other entities (A/AC.105/926).
4. The Working Group noted with satisfaction the work of the Action Team on
Near-Earth Objects, as reflected in the interim report of the Action Team
(A/AC.105/C.1/L.298).
5. The Working Group noted that the work accomplished on NEOs in the
intersessional period had resulted in important contributions to international
cooperation in that area. The Working Group also noted that international
conferences such as the conference entitled “Planetary Defense Conference:
Protecting Earth from Asteroids”, to be held in Granada, Spain, from 27 to 30 April
2009, and the conference entitled “Asteroid-Comet Hazard 2009”, to be held in
St. Petersburg, Russian Federation, from 21 to 25 September 2009, provided
opportunities to raise awareness among decision makers about the NEO threat and
to promote further cooperation.
6. The Working Group noted that international cooperation and coordination in
improving the Apophis ephemeris was important for obtaining a better
understanding of the threat to Earth posed by the Apophis asteroid. The Working
Group also noted that the period leading up to 2012 presented the best opportunity
to make preparations for carrying out international activities in that regard.
7. The Working Group heard a statement by the observer for the Association of
Space Explorers (ASE) on the work carried out by ASE in furthering the
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intersessional work of the Action Team on Near-Earth Objects under the item, in
accordance with the multi-year workplan of the Working Group.
8. The Working Group agreed that the report of ASE served as a good basis for
advancing the implementation of the workplan of the Working Group to continue
drafting, and seek agreement on, international procedures for handling the NEO
threat. In that context, the Action Team on Near-Earth Objects held four meetings
during the forty-sixth session of the Subcommittee to discuss and review the report
of ASE on the theme “Asteroid threats: a call for a global response”. On the basis of
those discussions, the Action Team prepared a conference room paper entitled
“Draft recommendations for near-Earth objects threat mitigation”
(A/AC.105/C.1/2009/CRP.13), for consideration by the Working Group.
9. The Working Group agreed that the Action Team on Near-Earth Objects should
continue the intersessional work, under the multi-year workplan, to further review
and develop draft recommendations for the international response to the threat of
NEO impacts, for consideration by the Working Group at the forty-seventh session
of the Subcommittee, in 2010. In that context, the Working Group encouraged
member States to participate in the intersessional work on NEO and submit their
contributions to the chairman of the Action Team.
10. At its 4th meeting, on 20 February 2009, the Working Group adopted the
present report."
United Nations General Assembly
Committee on the Peaceful, Uses of Outer Space, Fifty-second session, Vienna, 3-12 June 2009
Report of the Scientific and Technical Subcommittee
on its forty-sixth session, held in Vienna from 9 to
20 February 2009
Source Document
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"E. Mitigation
33. Mitigation in this context is the process of either negating or minimizing the
impact hazard posed to Earth by the sub-class of NEOs called potentially hazardous
objects, through some form of intervention or interaction with the risk body, or by
minimizing its impact on the population through evacuation or a similar response.
34. The European Space Agency (ESA) has supported industrial and academic
research studies on NEOs in the past. Those activities made it possible to identify a
project enabling Europe to make a significant yet realistic contribution to
international efforts to assess the NEO hazard. The result of that analysis was the
Don Quijote NEO technology demonstration mission, currently being defined by
European industrial teams. As a response to the call by the Council of Europe for
ESA to take an active role in the assessment of the NEO impact hazard, several
scientific and technical assessments were conducted. These were immediately
followed by parallel mission feasibility studies, whose outcome was assessed by the
Near-Earth Object Mission Advisory Panel of ESA, an independent panel of
recognized experts on various aspects of the NEO problem, which was set up by
ESA for that purpose. In accordance with the recommendations of the Panel
presented in July 2004, work focused on the Don Quijote mission concept, which
consists of two elements: a SMART-1-class, mini-satellite asteroid orbiter and a
modified upper stage serving as an asteroid impactor. The orbiter, called “Sancho”,
would rendezvous with a small, 500-metre near-Earth asteroid and study it before
the arrival of the impactor, called “Hidalgo”, which would hit it at a very high
relative speed. The Sancho orbiter would observe the impact and its results,
especially the resulting deflection in the asteroid’s trajectory. Suitable launch
opportunities for the first element, the orbiter, will begin in 2011. The impactor
could be launched four or five years later, which would allow for an independent or
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staged development of the two mini-satellites. The choice of the launch vehicle and
the suitable launch windows largely depends on the selection of the target asteroid,
which will be revisited by the Panel in the coming months. The mission has a
modular architecture, two separate small spacecraft and the possibility of an
independent asteroid “surface package”, which would facilitate its implementation
in the context of a cooperative project.
35. ESA recognizes that the efforts of major space agencies are now heading in
similar directions and are reaching the critical mass needed to attain concrete
developments with respect to space missions. Preparatory activities have enabled
ESA to gain a good understanding of the key issues of a realistic NEO technology
demonstration mission and have placed it in a good position to explore a way to
benefit from this convergence of interests or, at least, to establish an opportunity
partnership with another agency with the aim of identifying cost-sharing and/or
programmatic advantages.
36. With respect to observatory missions, the ESA Near-Earth Object Mission
Advisory Panel noted that improvements in the performance of the existing surveys
and, in particular, plans for larger facilities, had led to a dramatic increase over the
past few years in expectations for NEO discovery from the ground. The Panel
concluded that 80-90 per cent completeness for H<20.5 bodies (roughly 300 metres
in size) could be achieved within the next decade without a space observatory. The
Panel therefore recommended that the case for a space-based NEO observatory be
reconsidered in 10-15 years, after the residual hazard from NEOs that are not
accessible by ground-based surveys had been better defined.
37. On the other hand, the ESA Advisory Panel recognized that the current lack of
precise knowledge of the physical characteristics of NEOs would be a critical
limitation, should a potential impactor be identified. It therefore concluded that
rendezvous mission concepts were of significantly higher priority in terms of risk
assessment and mitigation than the observatory mission concepts. The Panel also
pointed out that given the variety of objects already known, it was improbable that
any rendezvous mission would investigate an NEO identical to the next impactor. It
therefore stressed the importance of a precursor mission concept aimed at
determining all the relevant quantities – size, density, internal structure, momentum
transfer, etc. – required to conduct an actual mitigation mission.
38. In February 2007, the Working Group on the Asteroid-Comet Impact Hazard
was established in the Russian Federation. Most governmental, research and
educational organizations in the Russian Federation are involved in the activities of
the Working Group. The Working Group is shortly to present a national programme
on the asteroid-comet impact hazard problem, which will include detection and
remote characterization, orbit determination and cataloguing, consequence
determination and mitigation at both the international and local levels.
39. The Institute of Planetary Research of DLR, in cooperation with the Dresden
University of Technology, is investigating potential techniques for diverting
asteroids and comets and is developing a tool that can determine an optimal
deflection strategy for a given impactor. Various potential techniques for diverting
asteroids and comets from a collision course with the Earth have been investigated
and modelled. In the course of that work, a software package to simulate a possible
impact scenario and to determine an optimal deflection strategy has been developed.
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The formation of craters and associated effects of asteroid or comet impacts on the
Earth, both on continents and on oceans, are currently being analysed in a
theoretical study involving advanced computer modelling and simulations.
40. The Institute of Planetary Research has also proposed the establishment of a
German Spaceguard Centre, which, like its existing counterparts in the
United States (the Jet Propulsion Laboratory) and the United Kingdom (the
NEO Information Centre), should act as a link between research activities and the
general public, convey scientific information in understandable terms to the public
and Government departments, and be prepared to support policymakers in
administering German participation in international activities in relation to the
impact hazard and NEO mitigation plans. This proposal has been considered by the
authorities in DLR and a decision on establishing the Centre is pending.
41. The United Kingdom funds a number of activities related to the mitigation of
the NEO hazard. The objective of the work conducted at the University of Glasgow
is to develop fundamental optimal control theory and apply it to the interception of
hazardous NEOs. The study has been moving along two parallel paths. The first is
the global optimization algorithms for an interplanetary trajectory. The tools that
have been developed are used to generate a number of possible trajectories to
intercept NEOs. Future work will develop more accurate models of the static and
dynamic properties of asteroids in order to study how those properties might
influence or even invalidate certain deviation methods. Assessments of other
deflection methods, such as the gravity tractor and the Yarkovski effect, will
continue.
42. The Action Team noted with interest the recent report of NASA to the
United States Congress, as requested by Congress in its 2005 NASA Authorization
Bill, to analyse possible alternatives that NASA could employ to divert an object on
a probable collision course with Earth. In that study, the NASA team assessed a
number of approaches that could potentially be used to divert an NEO on a
predicted collision course with Earth. The approaches are roughly divided into two
categories: “short impulse” options, where the diversion energy is applied in a near
instantaneous event; and “slow push” options, where the energy is applied over an
extended period of time. Important factors that require consideration in determining
the most effective techniques are: how much lead time the option requires or, in
other words, how much time would be available from detection of an impact threat
until the collision event, commonly referred to as “warning time”; how difficult it
would be to reach the threatening object (which is mostly a function of its orbital
path relative to the Earth’s); physical characterization of the threatening object; and
how much energy resource would be required to apply an effective amount of force
to the threatening object.
43. According to the findings of the NASA study team, the most promising short
impulse techniques were found to be the use of a stand-off nuclear device, in
particular for larger objects and especially when warning times were only a few
years, and the kinetic energy impactor. Both techniques make use of relatively
mature technology, almost all of which has been demonstrated at least in scenarios
similar to interplanetary space missions, and could be packaged into effective
systems placed on interplanetary trajectories with current lift capabilities.
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44. A variety of slow push techniques were presented to and analysed by the
NASA study team. However, almost all of the techniques are technically immature
(some are only preliminary concepts) and would have very limited application with
respect to the NEO threat unless warning times allowed mission durations of many
years or decades of diversion force application. The only viable slow push
techniques for further study were the space tug, which would attach to the
threatening object and change its trajectory with high-efficiency propulsion systems,
and the “gravity tractor”, which has the potential to alter the course of an object
using the gravitational attraction of a spacecraft station keeping in close proximity
to the object. Both techniques could be effective in scenarios that require only small
increments of velocity change (millimetres per second) and that concern relatively
small objects (less than 200 metres in the largest dimension). However, the space
tug would require more detailed characterization of the object, more robust
guidance and control and surface attachment technologies that are not available in
the near term.
45. The Action Team noted that the analysis by NASA of deflection options
covered only relatively large NEOs and did not consider the precision needed during
a deflection to avoid the potential of placing the NEO on a return impact trajectory.
46. The Action Team noted, overall, that in addition to the probability of impact
and time to impact, the other parameters that would influence the response strategy
were the anticipated intersect locus on the surface of the Earth and the vulnerability
of that area to the impact. The different options for deflection and the implications
of a particular deflection strategy – technical readiness, political acceptability, cost
of development and operation, translation of intersect locus – will also have to be
weighed up in relation to the alternatives. The Action Team acknowledged that it
was possible that a specific impact might threaten non-space-faring nations only. It
might be considered more attractive for one capable actor to take the lead in
mounting a particular deflection mission rather than a grouping of entities with
different roles, owing to the complexity of the mission and the political expediency
of protecting sensitive technical information. The Action Team therefore envisaged
a matrix of options setting out agreed responses to a range of impact scenarios and
identifying actors to perform specific roles. In that respect, the Action Team
identified the need for an international technical forum, where a range of probable
impactor scenarios could be determined and a corresponding matrix of mitigation
options to respond to a specific threat could be developed to a level of maturation
that would permit reliable mission timelines to be drawn up with a corresponding
decision timeline for the international community."
United Nations - General Assembly
Committee on the Peaceful
Uses of Outer Space
Scientific and Technical Subcommittee
Forty-fifth session
Vienna, 11-22 February 2008
Item 12 of the provisional agenda*
Near-Earth objects
Source
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