This area will cover relevant news of the threat to the planet from Near Earth Objects (NEOs) including concepts and designs for mitigation. All opinions are those of the author.

15 March 2007

Day 1: 2007 Plantetary Defense Conference - UPDATED

Introduction and Welcome
Dr. Bill Ailor
The Aerospace Coporation

Conference chairman Dr. Bill Ailor, from The Aerospace Corporation, provided introductory remarks. He stated that there were more sponsors this year than in previous years. The objectives for this conference were stated as follows:

Objectives of conference:
1. Threat posed by asteroid and comets
2. Mitigation approaches
3. Consequences of impacts
4. Human and disaster response dimensions
5. Political, policy, and legal issues
6. Develop a white paper with findings and recommendations

There will be various sessions including: Discovery and Characterization, Deflection Techniques, Deflection Missions and Technology, Impacts and Effects, Preparing the Public, Political and Policy issues, and finally a Panel Discussion. One of the outcomes of this conference is supposed is the creation of a white paper. This white paper will be discussed at the conference and most likely worked on for several months afterwards. There will be a reception at 5pm on 05 March 2007. In addition, there will be a Planetary Society special event at 7pm on 06 March 2007 (also at the Marvin Center).

Dr. Simon P. “Pete” Worden
Director, NASA Ames Research Center

Dr. Worden used to work with United States Senator Brownback (R-Kansas) on space issues. Apparently, the talk he gave at the last planetary defense conference in 2004 was one of his last within the military. There was an issue with his PowerPoint charts (as there seemed to be with many of the presentations, issues with the A/V setup). Worden said that he being “29 years in the Air Force [he] cannot talk without these charts.” Worden talked about the progress since 2004 in terms of the both space exploration and the NEOs. He placed emphasis on the Vision for Space Exploration (VSE), the major event since the last conference. He stated that we are well along on detecting large NEOs. He particularly mentioned Rusty Schweiert and other people’s work in getting public interested in Apophis,. He credited his colleagues with naming Apophis,, apparently his wife watches the television show Stargate in which there is a character with the same name. A big issue to him was where are we [they] are going to find money to do these things,. He stated that they do not yet have money to do much in this area and stated that everything we [they] do in this area needs to be colored [I assume by the implications of the VSE].

In terms of his point of the Vision for Space Exploration (VSE), he stated that the VSE involved a bipartisan support (see NASA Authorization Bill of 2005) that includes all the right words but does not make explicit statements on programs. The VSE includes statements that one of the key roles is to extend human presence through robotic exploration and international and commercial participation. He stated that the community needs to have the ability to take hardware for exploration and format some NEO studies from them.

Worden stated that in Congressional legislation for VSE, there are explicit instructions for NASA to conduct a survey program, with the appropriations bill specifically directing NASA to look at how to survey hazardous objects (I believe these were the 140m to 1km sized objects). Congress has asked NASA for a study to be delivered (the Analysis of Alternatives study, which was close to being delivered to Congress this week and mentioned repeatedly at the conference).

Warden said another major accomplishment since the last conference was that in 2004 Sen. Brownback had a hearing on NEOs. However, when Brownback went to his home district in Kansas and told the folks at the local barbershop about NEOs (and the Tunguska event), they laughed. This story was referred to several times during the conference as evidence of the “giggle” factor when it concerns NEOs. After this experience, Brownback stated that he was not going to talk about NEOs anymore.

Worden said that NASA 2006 Analysis of Alternatives (AoA) study was good and actually showed some charts from the study. Worden stated that if space-based NEO observation is pursued then his center will put forward proposals for such space-based assets. Worden stated that the NASA Administrator has told Congress recently that NASA will not reprogram any money into this area unless given explicit instructions and that this area [NEOs] “does not represent a new funding request or a commitment on the part of NASA.”

Recently, there have press articles about a NASA study that has looked at how to use exploration architecture elements such as the Crew Launch Vehicle (CLV) and Cargo Launch Vehicle (CaLV) for human missions to asteroid. Worden shed more light on this study by saying that many folks within NASA “conspired” to create and execute this study. Thus my interpretation is that this is a side study (one of many NASA normally does) by a small group with NASA and does not represent any mainline NASA Constellation Program office decision.

In regards to this idea of human asteroid missions, Worden stated that vision of the Orion Crew Exploration vehicle (CEV) hanging off asteroid like Itokawa (target of the Japanese Hayabusa mission) is an exciting one. Worden showed charts from this human asteroid mission study (apparently being worked upon by Ed Lu and others, the idea was initially brought to Worden by Lu). Particular charts Worden showed included various Earth-to-orbit (ETO) launch manifests for NEO mission launch concepts (including Ares I, IV, and V). Worden talked about charts that indicated that it would be quite feasible to send a human mission to an asteroid. He stated simple modifications would be needed for the CEV. This would result in minimal weight increases, potentially adding 587 lbs. From quickly scanning the charts it appeared that the mission would include a human crew of two for a 60-90 day mission. They have apparently examined several varieties of potential targets, but still do not today have a good set of targets using the Ares IV and Ares V launch vehicles. One body of interest discussed in the study was 2000 SG344. However, this object will not be available until 2069 for such a human asteroid mission. Thus there appears to be a need to find potential targets. Overall, Worden stated that human missions to asteroid are feasible and will raise general public/international interest, adding impetus to find the objects themselves.

Another piece of the NEO issue addressed by Worden was characterization. However, he addressed it in an unexpected manner (slightly unexpected by me and some in the audience). He stated that NASA Ames is trying to build nano-satellites Earth-to-Orbit (ETO) launch vehicles. Worden stated that satellites weighing 5-10 kg can be built that provide useful capabilities. He stated that such spacecraft could potentially have 1 kg of payload. They could be useful for a wide variety of NEO applications including a variety of in-situ studies for a few millions of dollars. This seemed to be a non-subtle advertisement for NASA Ames and its capabilities.

Worden also stated the obvious about this field, that the key limitation is money. He stated that NEOs are a key potential direction for the VSE. He stated that they are implicit in everything NASA is doing, could be more explicit as time goes on. He stated that the possibilities of affordable nano-satellites are very interesting. Worden concluded his main remarks by stating that there is still some “giggle factor” on this issue but the large number of sponsors of the 2007 conference (as compared to the 2004 conference) shows that this problem is lessening, though it is still somewhat of an issue. Worden stated that people should “hit other NASA people for money, not me.”

In the question and answer (Q&A) session there was discussion of using nano-satellites for Low Earth Orbit (LEO) access. There may be more done with secondary payloads (see the ESPA secondary payload adapter recently launched on the Atlas V orbital express mission). Worden stated that interesting things can be done with smallsats. As an example, he has asked people if they could figure out what they can do for 1 kg of payload in different locations in the solar system (paraphrase: “If I gave you a kilogram in the right location, what can you do?”). There was talk that nanotechnology could also be an enabler.

Worden stated that on that particular day he was going to talk out the Department of Defense. He stated that he loves to spend their money. He told the audience about talking to a colonel about this issue, specifically talking about the K-T impactor 6 5million years ago. The response was that if there was not going to a large probability of an event this year, and that it could be a few million years, they the DoD thinks they can defer this issue until next year. The moral of this story is that the budget horizons of these agencies is very short and that the most likely funding will not be for missions but technology development. He stated the obtaining DoD funding [edited from original post] of the Clementine mission to the moon was an “artful conspiracy.”

Session 1A: Discovery & Characterization
Chair: David Morrison, NASA Ames Research Center

Note: David Morrison currently describes himself as an astrobiologist.

Poster Papers: Several of the poster paper presenters did not show up. Presenters for the Gritsevich, Ivashkin, and Bagrov poster papers did not show up. A paper from Messrs. Cleve and Arentz from Ball Aerospace was the only paper presented during the interactive poster session at the beginning of this session. Like other conferences, this conference has been experimenting with giving traditional poster papers (papers normally not given a speaking slot) 2-3 minutes to present an overview of their work. The upcoming International Astronautical Conference (IAC) will also be having these “interactive” poster sessions. Cleve presented in place of Bob Arentz on “The Impact of Deep Impact.” The short presentation went over the Deep Impact mission (an approximately 400 kg impactor spacecraft). Cleve suggested that kinetic energy deflection is attractive if warning times are less than 30 years.

Current NASA Discovery/Characterization Efforts: The Recommendations of the 2003 SDT report and the Dec. 2005 Congressional request
Donald Yeomans
NASA Jet Propulsion Laboratory

There are 350,000 minor planets. Yeomans went through a history of recent NEO workshops and government reports. This included the 1992 Near-Earth Object Interception Workshop that took place in Washington, D.C. that favored nuclear intercept and recommended a 2.5 m optical telescope for NEOs. In 1995 the “Eugene Shoemaker report” (the 1995 Near Earth Objects Survey Workgroup Report) related that 90% of objects over 1km in diameter should be found, which became the NASA headquarters goal to the House Science Committee. He then related the goals of the current Spacegaurd survey (find 90% of all NEAs larger than 1 km in diameter by the end of 2008). Yeomans said the new NASA report, the Analysis of Alternatives report to Congress, will get a limited release (later on in the conference, he stated that only about 100 copies has been printed for distribution and though that only a summary version of the report would be presented). At this point in the conference, he was not sure if the report was delivered to Congress.

Yeomans stated that Apophis is the poster child for near earth objects. Every 600 years it passes close to the Earth and is expected to hit the Earth every 23,000 years. He stated that Apophis is a 270 m sized [diameter] object discovered in June 2004 and that on April 13, 2029 it will pass 5.06 radaii above Earth’s surface, having a 1/45,000 chance of Earth impact in 2036. He stated Apophis will be a “naked eye” object for people living in western Europe/northern Africa (Apophis will have a magnitude of 3.5, note: the star Sirius shines at magnitude –1.5, Venus is as –4.4, and the full Moon is about –12.5). Apophis will be traveling through the constellation Cancer at 42 degrees per hour.

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