Figure 21 - uploaded by R. B. Adams
Content may be subject to copyright.
Source publication
SEVERAL RECENT NEAR-MISS ENCOUNTERS WITH ASTEROIDS AND COMETS HAVE FOCUSED ATTENTION ON THE THREAT OF A CATASTROPHIC IMPACT WITH THE EARTH. THIS TECHNICAL PUBLICATION REVIEWS THE HISTORICAL IMPACT RECORD AND CURRENT UNDERSTANDING OF THE NUMBER AND LOCATION OF NEAR-EARTH OBJECTS (NEOS) TO ADDRESS THEIR IMPACT PROBABILITY. VARIOUS ONGOING PROJECTS IN...
Similar publications
This Technical Memorandum covers revolutionary ideas for space radiation shielding that would mitigate mission costs while limiting human exposure, as studied in a workshop held at Marshall Space Flight Center at the request of NASA Headquarters. None of the revolutionary new ideas examined for the .rst time in this workshop showed clear promise. T...
This assessment had two Phases. Phase I captured NASA Centers’ current practices for commercial-off-the-shelf (COTS) Electrical, Electronic, and Electromechanical (EEE) parts1 used in spaceflight systems and ground support equipment (available at https://ntrs.nasa.gov/citations/20205011579) [ref. 1]. The Phase II report provides guidance for select...
Ion beam figuring provides a highly deterministic method for the final
precision figuring of optical components with advantages over
conventional methods. The process involves bombarding a component with a
stable beam of accelerated particles that selectively removes material
from the surface. Figure corrections are achieved by rastering the
fixed-...
This paper proposes a matrix-based modeling approach for analyzing spaceflight campaign logistics. A campaign is considered to be a series of coordinated flights delivering cargo at a location or node. A matrix representation of the cargo carried by flights for consumption in different time periods (or missions) is formulated. The matrix adopts spe...
Citations
... Given this history and the potential for large impacts there is the clear need to be able to quickly protect the Earth from an incoming comet or asteroid by altering the intruder's orbit. Ways of doing this depend in part on how far out in time the object is identified, and are surveyed in 2004 NASA [21] and 2010 NRC (NAS) reports [22]. For decades of warning, (which may be the case for most discovered asteroids with three to seven year orbits), one can develop different deflection techniques than for cases with only months of warning. ...
... A 2007 NASA Report to Congress on ''Near-Earth Object Survey and Deflection Analysis of Alternatives'' [28] concluded that a nuclear detonation near to an asteroid or comet is the best way to achieve the required deflection, especially in the case of a large object, and limited response times. In the 2004 NASA report [21], ''nuclear deflection'' (not nuclear fragmentation) is defined as using an intense radiation burst to cause sudden heating of the surface of the object, which ablates off material from the object's surface, resulting in a rocket effect. One would consider using the largest nuclear explosives ever tested (10-50 Megatons), consistent with getting them into deep space, and setting them off within 1 km distance of the target object. ...
The sentence, “It was named C/2013 A1 (at 56 km/s, 0.7 km in diameter, weighing 3 × 108 metric Tons, it had 4 billion megatons of kinetic energy).” should read as.
... A variety of NEO deflection/disruption technologies, including kinetic impactors, gravity tractors, and nuclear explosions, have been investigated by planetary defense researchers during the past two decades [1][2][3][4][5][6][7]. Kinetic impactors and nuclear explosions are the most practically viable technologies for asteroid deflection or disruption, as concluded in the 2010 NRC report [6]. ...
This paper presents an overview of space mission concepts for disrupting or pulverizing hazardous asteroids, especially with warning time shorter than approximately 10 years. An innovative mission concept, referred to as a nuclear hypervelocity asteroid intercept vehicle (HAIV) system, employs both a kinetic-energy impactor and nuclear explosive devices. A new mission concept of exploiting a multiple kinetic-energy impactor vehicle (MKIV) system that doesn’t employ nuclear explosives is proposed in this paper, especially for asteroids smaller than approximately 150 m in diameter. The multiple shock wave interaction effect on disrupting or pulverizing a small asteroid is discussed using hydrodynamic simulation results. A multi-target terminal guidance problem and a planetary defense mission design employing a heavy-lift launch vehicle are also brie y discussed in support of the new non-nuclear MKIV mission concept. The nuclear HAIV and non-nuclear MKIV systems complement to each other to effectively mitigate the various asteroid impact threats with short warning time.
... 3 A wide variety of strategies, including nuclear standoff detonation, mass drivers, kinetic-energy projectiles, and low-thrust deflection via electric propulsion or solar sails, have been proposed to deal with the technically challenging asteroid mitigation problem. 4 In spite of the significant interest in asteroid deflection, and the extensive research by the community, the operation of spacecraft in their vicinity remains a challenging problem. ...
This paper considers the coupled orbit and attitude dynamics of a dumbbell spacecraft around an asteroid. Geometric methods are used to derive the coupled equations of motion, defined on the configuration space of the special Euclidean group, and then a nonlinear controller is designed to enable trajectory tracking of desired landing trajectories. Rather than relying on sliding mode control or optimization based methods, the proposed approach avoids the increased control utilization and computational complexity inherent in other techniques. The nonlinear controller is used to track a desired landing trajectory to the asteroid surface. A monocular imaging sensor is used to provide position and attitude estimates using visual odometry to enable relative state estimates. We demonstrate this control scheme with a landing simulation about asteroid Itokawa.
... Given this history and the potential for large impacts there is the clear need to be able to quickly protect the Earth from an incoming comet or asteroid by altering the intruder's orbit. Ways of doing this depend in part on how far out in time the object is identified, and are surveyed in 2004 NASA [21] and 2010 NRC (NAS) reports [22]. For decades of warning, (which may be the case for most discovered asteroids with three to seven year orbits), one can develop different deflection techniques than for cases with only months of warning. ...
... A 2007 NASA Report to Congress on ''Near-Earth Object Survey and Deflection Analysis of Alternatives'' [28] concluded that a nuclear detonation near to an asteroid or comet is the best way to achieve the required deflection, especially in the case of a large object, and limited response times. In the 2004 NASA report [21], ''nuclear deflection'' (not nuclear fragmentation) is defined as using an intense radiation burst to cause sudden heating of the surface of the object, which ablates off material from the object's surface, resulting in a rocket effect. One would consider using the largest nuclear explosives ever tested (10-50 Megatons), consistent with getting them into deep space, and setting them off within 1 km distance of the target object. ...
We argue that it is essential for the fusion energy program to identify an imagination-capturing critical mission by developing a unique product which could command the marketplace. We lay out the logic that this product is a fusion rocket engine, to enable a rapid response capable of deflecting an incoming comet, to prevent its impact on the planet Earth, in defense of our population, infrastructure, and civilization. As a side benefit, deep space solar system exploration, with greater speed and orders-of-magnitude greater payload mass would also be possible.
... Given this history and the potential for large impacts there is the clear need to be able to quickly protect the Earth from an incoming comet or asteroid by altering the intruder's orbit. Ways of doing this depend in part on how far out in time the object is identified, and are surveyed in 2004 NASA [21] and 2010 NRC (NAS) reports [22]. For decades of warning, (which may be the case for most discovered asteroids with three to seven year orbits), one can develop different deflection techniques than for cases with only months of warning. ...
... A 2007 NASA Report to Congress on ''Near-Earth Object Survey and Deflection Analysis of Alternatives'' [28] concluded that a nuclear detonation near to an asteroid or comet is the best way to achieve the required deflection, especially in the case of a large object, and limited response times. In the 2004 NASA report [21], ''nuclear deflection'' (not nuclear fragmentation) is defined as using an intense radiation burst to cause sudden heating of the surface of the object, which ablates off material from the object's surface, resulting in a rocket effect. One would consider using the largest nuclear explosives ever tested (10-50 Megatons), consistent with getting them into deep space, and setting them off within 1 km distance of the target object. ...
... Given this history and the potential for large impacts there is the clear need to be able to quickly protect the Earth from an incoming comet or asteroid by altering the intruder's orbit. Ways of doing this depend in part on how far out in time the object is identified, and are surveyed in 2004 NASA [21] and 2010 NRC (NAS) reports [22]. For decades of warning, (which may be the case for most discovered asteroids with three to seven year orbits), one can develop different deflection techniques than for cases with only months of warning. ...
... A 2007 NASA Report to Congress on ''Near-Earth Object Survey and Deflection Analysis of Alternatives'' [28] concluded that a nuclear detonation near to an asteroid or comet is the best way to achieve the required deflection, especially in the case of a large object, and limited response times. In the 2004 NASA report [21], ''nuclear deflection'' (not nuclear fragmentation) is defined as using an intense radiation burst to cause sudden heating of the surface of the object, which ablates off material from the object's surface, resulting in a rocket effect. One would consider using the largest nuclear explosives ever tested (10-50 Megatons), consistent with getting them into deep space, and setting them off within 1 km distance of the target object. ...
Abstract: We argue that it is essential for the fusion energy program to identify an imagination-capturing critical mission by developing a unique product which could command the marketplace. We lay out the logic that this product is a fusion rocket engine, to enable a rapid response capable of deflecting an incoming comet, to prevent its impact on the planet Earth, in defense of our population, infrastructure, and civilization. As a side benefit, deep space solar system exploration, with greater speed and orders-of-magnitude greater payload mass would also be possible.
... Long-duration, low-thrust methods include solar ablation [1,2], laser ablation [3], mass driver [4], gravity tractor [5,6], solar sail [7,8], NEO painting [9], enhanced Yarkovsky effect [10], recently the novel long tether and ballast method [11,12], and high specific impulse rocket [13]. The deflection capability of these methods is relatively limited, and they require a long time to achieve a significant deflection. ...
... High-energy impulsive methods include kinetic impact (with or without explosives) [14], nuclear explosion [15], magnetic flux compression [1], and chemical rocket [9]. If the threatening NEO is sufficiently large, these methods may yield no deflection. ...
Using a small near-Earth object (NEO) to impact a larger and potentially threatening NEO has been suggested as an effective method to avert a collision with Earth. This paper develops a procedure for analysis of the technique for specific NEOs. First, an optimization method is used to select a proper small body from the database. Some principles of optimality are achieved with the optimization process. Then, the orbit of the small body is changed to guarantee that it flies toward and impacts the big threatening NEO. Kinetic impact by a spacecraft is chosen as the strategy of deflecting the small body. The efficiency of this method is compared with that of a direct kinetic impact to the big NEO by a spacecraft. Finally, a case study is performed for the deflection of the Apophis NEO, and the efficiency of the method is assessed.
... In the early 1990s, scientists around the world initiated studies to prevent NEOs from striking Earth [1]. However, it is now 2009, and there is no consensus on how to reliably deflect them in a timely manner even though various mitigation approaches have been investigated during the past two decades [1][2][3][4][5][6][7][8]. Consequently, now is the time for initiating a concerted R&D effort for developing practically viable deflection technologies before any NEOs are discovered heading toward Earth. ...
... Assuming that NEOs on a collision course can be detected prior to impact with a mission lead time of at least 10 years, however, the challenge becomes eliminating their threat, either by destroying the asteroid, or by altering its trajectory so that it will miss Earth. A variety of schemes have been already extensively investigated in the past for such a technically challenging, asteroid deflection problem [1][2][3][4][5][6][7][8]. The feasibility of each approach to deflect an incoming hazardous object depends on its size, spin rate, composition, the mission lead time, and many other factors. ...
The John V. Breakwell Memorial Lecture for the As-trodynamics Symposium of the 60th International As-tronautical Congress (IAC) presents a tutorial overview of the astrodynamical problem of deflecting a near-Earth object (NEO) that is on a collision course toward Earth. This lecture focuses on the astrodynamic fundamentals of such a technically challenging, complex engineering problem. Although various deflection technologies have been proposed during the past two decades, there is no consensus on how to reliably deflect them in a timely manner. Consequently, now is the time to develop prac-tically viable technologies that can be used to mitigate threats from NEOs while also advancing space explo-ration.
... Assuming that NEAs on a collision course can be detected before impact with a mission lead time of at least 10 years, however, the challenge becomes eliminating their threat, either by destroying the asteroid or by altering its trajectory so that it will miss Earth. A variety of schemes, including a nuclear standoff detonation, mass drivers, kinetic-energy projectiles, laser beaming, and low-thrust deflection via electric propulsion or solar sails, have been already extensively investigated in the past for such a technically challenging asteroid deflection problem [3][4][5][6][7]. The feasibility of each approach to deflect an incoming hazardous object depends on its size, spin rate, composition, the mission lead time, and many other factors. ...
Multiple gravity tractors in halo orbits and a hovering solar sail gravity tractor are proposed as an option for deflecting a certain class of near-Earth asteroids that may not require high-energy deflection techniques employing nuclear explosions or kinetic impactors. This paper presents the preliminary dynamic modeling and control analysis of such variants of the gravity tractor for examining their practical viability as applied to asteroid Apophis; however, detailed system-level tradeoffs are not treated in this paper. A system of orbiting multiple gravity tractors has many advantages over the hovering gravity tractor. They include its larger total Delta V capability, multispacecraft redundancy, and mission design flexibility with smaller satellites equipped with lower-risk propulsion systems. A solar sail gravity tractor concept exploits the propellantless nature of solar reflectors despite its inherent drawback of requiring a particular hovering position with a 55-deg offset angle from the target asteroid's flight direction.
... The Ares V specifications and performance is also listed in Table 1. 2 n/a n/a 134,483 lbm -2 km 2 /sec 2 n/a 5146 lbm 133,585 lbm 0 km 2 /sec 2 n/a n/a 129,600 lbm 10 km 2 /sec 2 n/a n/a 111,262 lbm The Ares V performance to the various values of C3, are based on a direct ascent trajectory and the complete exhaustion of the EDS propellant. Ares V performance to LEO in the preceding table is based on burning 290,000 lbm of EDS propellant in a sub-orbital burn with 218,519 lbm of propellant remaining. ...
... The authors decided upon two computer applications for modeling the outbound and inbound trajectory legs for the deflection scenarios -Planetary Body Intercept (PBI) and Copernicus. PBI, which only considers impulsive maneuvers, was developed specifically for planetary body maneuvering analysis and was used in the previous study 2 to analyze the inbound planetary body trajectories. PBI reads from an input file the position and velocity vectors of the earth and planetary body at the time of impact, integrates the equations of motion backward in time by a user-specified number of days, and then determines the impulsive delta-v required to make the planetary body miss Earth by a specified distance. ...
