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From page 464... ... 464 ORIGINS, WORLDS, AND LIFE FIGURE 17-6 At present selection rates, NASA is missing out on substantial high-quality science. Shown here are the proportions of selected proposals (above the waterline) Read the entire page →
From page 465... ... RESEARCH AND ANALYSIS 465 The current FY 2023 PSD budget is $3.2 billion, and the currently planned FY 2023 R&A level is $249 million (7.9 percent) , with approximately $185 million of this for openly competed programs (based on a 2 percent/year increase in non-openly competed activities for nondecadal years; see Box 17-2) Read the entire page →
From page 466... ... 466 ORIGINS, WORLDS, AND LIFE pressure on available funds, and a repeating cycle of declining selection rates. In this situation, it is appropriate to consider how we can best shepherd sustainable growth of the community without being unwitting gatekeepers and propagating structural inequities that may contribute to a less diverse workforce. Read the entire page →
From page 467... ... RESEARCH AND ANALYSIS 467 As detailed above, the committee recommends that the R&A annual budget be increased to ≥10 percent of the PSD annual budget by mid-decade, implying that by the decade's end, annual funding for openly competed programs would be >$400 million [>$300 million] in the Recommended [Level] Read the entire page →
From page 468... ... 468 ORIGINS, WORLDS, AND LIFE astrobiology, as well as those more closely related -- including, but not limited to, the quickly growing commercial space sector. Educating planetary science and astrobiology graduate students on career paths outside the traditional academic track (i.e., government, nonprofit, and industry sectors) Read the entire page →
From page 469... ... RESEARCH AND ANALYSIS 469 Another example where NSF and NASA could benefit from closer cooperation is in analogue research through the infrastructure, data, and samples offered by scientific ocean drilling programs (Neal et al. Read the entire page →
From page 471... ... 18 Planetary Defense: Defending Earth Through Applied Planetary Science Planetary defense is an international cooperative enterprise aimed at providing protection to the nations of the world from devastating asteroid and comet impacts. Through the use of the knowledge and tools gained through planetary science and exploration, it is now possible to develop realistic and cost-effective detection and mitigation strategies against these natural disasters. Read the entire page →
From page 472... ... 472 ORIGINS, WORLDS, AND LIFE FIGURE 18-1 The known and extrapolated population of near-Earth asteroids (N) in terms of estimated diameter (D) Read the entire page →
From page 473... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 473 FIGURE 18-2 The chart above shows reported fireball events for which geographic location data are known. Each event's calculated total impact energy is indicated by its relative size and color. Read the entire page →
From page 474... ... 474 ORIGINS, WORLDS, AND LIFE FIGURE 18-3 Near-Earth object discoveries over time, showing the accelerating rate of NEO detection from ground-based search programs. Data current as of February 16, 2023. Read the entire page →
From page 475... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 475 NEOs for any potential impacts via its Sentry impact monitoring system, and monitors potential newly discovered NEOs via its Scout hazard assessment system. NASA and NSF have broad expertise in both the scientific exploration and characterization of NEOs. Read the entire page →
From page 476... ... 476 ORIGINS, WORLDS, AND LIFE The Brown Act survey goals are based on the findings of a 2003 NASA science definition team study (NASA 2003) Read the entire page →
From page 477... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 477 funding for full-scale development in the 2022 President's Budget Request, funding is not yet assured, and the mission is not yet confirmed. Finding: The first priority in planetary defense is early detection, tracking, and characterization of NEOs, whose im pact may cause widespread regional damage. Read the entire page →
From page 478... ... 478 ORIGINS, WORLDS, AND LIFE Mega-Satellite Constellations and NEO Surveys An increasing threat to the ability of ground-based telescopes to detect and characterize NEOs comes from existing and planned mega-constellations of low-Earth-orbiting (LEO) satellites (e.g., Starlink) Read the entire page →
From page 479... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 479 cause it to detonate near/at Earth's surface. The NEO's physical characteristics also have bearing on the effectiveness of various space deflection/mitigation techniques. Read the entire page →
From page 480... ... 480 ORIGINS, WORLDS, AND LIFE type and are visible by many people. Modeling and accurately predicting the visibility range and brightness of these small impacting NEOs will enhance the credibility of the NEO activities and improve the predictions of the magnitude of expected explosions. Read the entire page →
From page 481... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 481 initial orbit determinations of potentially hazardous NEOs (99942) Apophis and 2020 NK1 indicated a significant chance of Earth impact, but radar observations were able to quickly rule out a collision hazard. Read the entire page →
From page 482... ... 482 ORIGINS, WORLDS, AND LIFE and planned telescope programs to improve detection and tracking" of NEOs, as well as to identify "opportunities in existing and new telescope programs to enhance characterization of NEO composition and dynamical and physical properties" (NSTC 2018) Read the entire page →
From page 483... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 483 The extremely precise Apophis flyby prediction provides an unprecedented opportunity for multiple observatories to coordinate simultaneous pre- and post-encounter observations of the NEO from multiple viewing geometries and at wavelengths from optical to radar. Owing to its inherent interest, Apophis is already a target of opportunity for astronomers, with every apparition leading to significant observations focused on determining its orbit, shape, spin state, and thermal and spectral properties. Read the entire page →
From page 484... ... 484 ORIGINS, WORLDS, AND LIFE NEO MODELING, PREDICTION, AND INFORMATION INTEGRATON Goal 2 of the National Near-Earth Object Preparedness Strategy and Action Plan focuses on advancement of modeling and analysis capabilities, including the assessment of impact probabilities, location, consequences, and mitigation options. The initial conditions and attendant uncertainties for these modeling efforts depend heavily on the detection, tracking, and characterization of NEOs (see NEO Detection, Tracking, and Characterization section) Read the entire page →
From page 485... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 485 more collaborative work is needed to understand the sources of these differences and to refine simulation capabilities. The interagency NEO MWG, led by the NASA Ames Research Center, has begun working through representative impact studies. Read the entire page →
From page 486... ... 486 ORIGINS, WORLDS, AND LIFE past decade, owing to advances in high performance computing, improved understanding of NEO initial conditions from spacecraft data, and focused research. Improvements include more realistic modeling of rubble pile structures, variable distributions of macro- and microporosity, improved strength and damage models representing asteroidal material, and simulation of a wider range of three-dimensional NEO shapes. Read the entire page →
From page 487... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 487 Laboratory (EIL) , many planetary defense questions will remain unaddressed. Read the entire page →
From page 488... ... 488 ORIGINS, WORLDS, AND LIFE NEO DEFLECTION AND DISRUPTION MISSIONS One of the overarching strategic goals of the National Near-Earth Object Preparedness Strategy and Action Plan is developing capabilities for NEO impact prevention. Goal 3 of the action plan outlines the activities that NASA will lead to strengthen the U.S. Read the entire page →
From page 489... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 489 of the DART results and apply them to broader mitigation technology efforts to achieve an effective and versatile PD capability. Similarly, the launch of NASA's NEO Surveyor in 2026 will greatly expand our knowledge of the NEO population over the next decade, which will help inform the PD activities that follow. Read the entire page →
From page 490... ... 490 ORIGINS, WORLDS, AND LIFE characterize via ground-based methods, and represent the least understood, but statistically the most likely subset of the NEO population to require mitigation actions. For NEOs with short warning times, rapid characterization may be required in order to implement appropriate mitigation measures. Read the entire page →
From page 491... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 491 FIGURE 18-4 Numerical results from simulating deflection capabilities of various techniques across a variety of asteroid sizes following fifteen different Earth-impacting orbits. Kinetic impact (KI) Read the entire page →
From page 492... ... 492 ORIGINS, WORLDS, AND LIFE parameter space between the kinetic impact and ion beam deflection techniques. Please see the RMA study for additional details (NASA 2021c) Read the entire page →
From page 493... ... PLANETARY DEFENSE: DEFENDING EARTH THROUGH APPLIED PLANETARY SCIENCE 493 Promising Planetary Defense Mission Technologies There are several promising technologies whose pursuit would help attain specific goals of PD characterization and mitigation missions. These technologies can be broadly grouped into several categories and are utilized in mission architectures for flyby/intercept and rendezvous PD concepts. Read the entire page →
From page 494... ... 494 ORIGINS, WORLDS, AND LIFE Finding: Promising new technologies for both characterization and mitigation demonstration missions could be tested on relevant NEOs. Technologies such as those for guidance, navigation, and control (GNC) Read the entire page →

From page 464...

... 464 ORIGINS, WORLDS, AND LIFE FIGURE 17-6 At present selection rates, NASA is missing out on substantial high-quality science. Shown here are the proportions of selected proposals (above the waterline)