NASA recently had to give their latest report on the NEO issue to congress, and the report was, well, not very optimistic.
First, here is the bleak assessment signed by Michael D. Griffin, the NASA Administrator-
This is a complex issue, potentially involving many other U.S. Government agencies and international organizations ... I look forward to working with the Administration and Congress in setting realistic goals for a NEO survey program given the challenging demands already placed on NASA resources… NASA recommends that the [current Spaceguard] program continue as currently planned, and we will also take advantage of opportunities using potential dual-use telescopes and spacecraft—and partner with other agencies as feasible—to attempt to achieve the legislated goal within 15 years. However, due to budget constraints, NASA cannot initiate a new program at this time.
Here's the congressional mandate-
From Section 321 of the NASA Authorization Act of 2005, the objectives of the NEO survey program are to detect, track, catalogue, and characterize the physical characteristics of NEOs equal to or larger than 140 meters in diameter with a perihelion distance of less than 1.3 AU, achieving 90 percent completion within 15 years. NASA is directed to provide a report to Congress that provides: (1) an analysis of possible alternatives that NASA may employ to carry out the survey program of NEOs, including groundbased and spacebased alternatives with technical descriptions; (2) a recommended option; and (3) an analysis of possible alternatives that NASA could employ to divert an object on a likely collision course with Earth.
So the issue here is that the mandate Congress laid out (a weak mandate at that) is not going to be achieved within 15 years due to the current budget restraints.
That means that the International Space Station (the one where the rest of the world was supposed to pitch in to help pay for it) which has several billion dollars worth of NASA's resources tied up is a FAR more important project than achieving the congressional mandate for NEO's. NEO-related projects at NASA have rarely ever reached the tens of millions of dollars of NASA's budget. NASA gets by on $15-20 billion a year. Therefore, one could say, NEO-related projects have never been anywhere near as much of a priority with NASA as the floating port-a-potty that is the International Space Station.
I have nothing against the ISS. It's cool and all- learning how spiders spin webs in zero gravity, the effects of space on the human body, and the other various scientific projects that the fine folks at NASA pour their hearts and sould in to. I have a lot respect for the work that has been done as it is remarkable.
But my point, which I've been pounding on since pretty much day one of this blog, is that NONE of these ISS projects will mean anything if and when we find a potentially threatening asteroid on its way to earth. If this happens it will make every other space related project irrelevant, and most earth bound ones as well. And the numbers don't lie. We WILL get whacked again. It is simply a matter of time.
Back to the report-
A study team, led by NASA's Office of Program Analysis and Evaluation (PA&E), conducted the analysis of alternatives with inputs from several other U.S. government agencies, international organizations, and representatives of private organizations. The team developed a range of possible options from public and private sources and then analyzed their capabilities and levels of performance including development schedules and technical risks.
Key Findings for the Survey Program:
* The goal of the Survey Program should be modified to detect, track, catalogue, and characterize, by the end of 2020, 90 percent of all Potentially Hazardous Objects (PHOs) greater than 140 meters whose orbits pass within 0.05 AU of the Earth's orbit (as opposed to surveying for all NEOs).
* The Agency could achieve the specified goal of surveying for 90 percent of the potentially hazardous NEOs by the end of 2020 by partnering with other government agencies on potential future optical ground-based observatories and building a dedicated NEO survey asset assuming the partners' potential ground assets come online by 2010 and 2014, and a dedicated asset by 2015.
* Together, the two observatories potentially to be developed by other government agencies could complete 83 percent of the survey by 2020 if observing time at these observatories is shared with NASA's NEO Survey Program.
* New space-based infrared systems, combined with shared ground-based assets, could reduce the overall time to reach the 90 percent goal by at least three years. Space systems have additional benefits as well as costs and risks compared to ground-based alternatives.
* Radar systems cannot contribute to the search for potentially hazardous objects, but may be used to rapidly refine tracking and to determine object sizes for a few NEOs of potentially high interest. Existing radar systems are currently oversubscribed by other missions.
* Determining a NEO's mass and orbit is required to determine whether it represents a potential threat and to provide required information for most alternatives to mitigate such a threat. Beyond these parameters, characterization requirements and capabilities are tied directly to the mitigation strategy selected.
Again, most of the key points raised show that with a little more help from Congress budget wise, and maybe a little assistance from the international community, the goals laid out in the congressional mandate are feasable. The problem is that this isn't going to happen.
Then we start to discuss current mitigation theories for dealing with a potential threat, and things get, um, a little less hopeful.
Key Findings for Diverting a Potentially Hazardous Object (PHO):
The study team assessed a series of approaches that could be used to divert a NEO potentially on a collision course with Earth. Nuclear explosives, as well as non-nuclear options, were assessed.
* Nuclear standoff explosions are assessed to be 10-100 times more effective than the non-nuclear alternatives analyzed in this study. Other techniques involving the surface or subsurface use of nuclear explosives may be more efficient, but they run an increased risk of fracturing the target NEO. They also carry higher development and operations risks.
* Non-nuclear kinetic impactors are the most mature approach and could be used in some deflection/mitigation scenarios, especially for NEOs that consist of a single small, solid body.
* "Slow push" mitigation techniques are the most expensive, have the lowest level of technical readiness, and their ability to both travel to and divert a threatening NEO would be limited unless mission durations of many years to decades are possible.
* 30-80 percent of potentially hazardous NEOs are in orbits that are beyond the capability of current or planned launch systems. Therefore, planetary gravity assist swingby trajectories or on-orbit assembly of modular propulsion systems may be needed to augment launch vehicle performance, if these objects need to be deflected.
Read that last part again -"30-80 percent of potentially hazardous NEOs are in orbits that are beyond the capability of current or planned launch systems." The B612 Project/Foundation has designed multiple plans for a gravity assist type project, and it has proposed testing out our abilities with a transponder mission for the upcoming flyby of asteroid 99942 Apophis.
My proposal for dealing with this issue is take half of the measly few million that they spend on NEO projects, and GIVE HALF OF IT TO the B612 Foundation.
Yet another huge government project that proves why government is never the answer to the problem, and perhaps even part of the problem.
Here is the response that Rusty Schweickart sent in response to NASA's report to congress. The main thrust of his analysis is the following-
Because of the “hypothetical scenarios” presented in the NASA Report to Congress the nuclear options are either best suited to the task or absolutely required. This selection of specialized scenarios is not, however, representative of the deflection cases most likely to be encountered. The highest probability impacts will always correlate with the smallest NEOs and, based on the assumption that the world will not choose to “take the hit” of a Tunguska-like object if its potential impact is known ahead of time, this cohort of NEOs is selected in this analysis as the lower limit of the pragmatic threat cohort. 99% of the NEOs in this cohort are more likely to call for deflection than those cases selected in the NASA Congressional Report.
Again, why don't we put them in charge?
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