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Brian Weeden, Wednesday, 10-23-13 October 23, 2013

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Brian Weeden, Wednesday, 10-23-13


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Guest:  Brian Weeden.  USAF Space Fence for national security.  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, https://thespaceshow.wordpress.com.  Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See www.onegiantleapfoundation.org/amazon.htm.

We welcomed Brian Weeden back to the program to discuss the issue of the shutting down of the USAF Space Fence.  Our discussion was based on Brian’s August 26, 2013 Space Review article, “Gambling with a Space Fence: An analysis of the decision to shut down the Air Force Space Surveillance Fence” at www.thespacereview.com/article/2357/1.  During the first segment of our 1 hour 29 minute discussion, Brian provided us with a brief history of the Space Fence, what it has been used for, its technical characteristics, and it recent cancellation partially due to sequestration regarding its approximate $15 million annual budget expense.  Brian also explained its capabilities in detecting spy satellites, space debris and other objects and the size of objects which it can detect.  He discussed both continuous wave radar and pulsed radar, pointing out that the fence which dated from the late 1950’s, was uncued.  Richard Easton called in as his father Roger was one of the developers for the space fence in January 1958.  Richard contributed greatly to our discussion.  Brian then talked about the probable replacement for the fence, an S Band fence which would result in higher frequencies enabling the detection of smaller objects, probably with a very high rate pulsed radar. Right now the S Band fence is estimated to cost about $1.8 billion but as you will hear, it may never be built.  As to how our national security has been impacted without the fence operating, Brian said it was difficult to assess so listen carefully to his analysis.  Brian also talked about challenging DOD budget issues, the difference in budget years with DOD as compared to the government as a whole, and again, sequestration.

In our second segment, Brian addressed several of the political issues surrounding the space fence issue.  When asked how long it would take for the S Band system to become operational were it funded, he said around 2018.  Two companies are competing to do it if and when the project is authorized and funded.  We also talked about the U.S. sharing satellite tracking information with all satellite operators including private companies, thus using an international partnership to finance the space fence since it benefits everyone. As you will hear, there appears to be control and sensitivity issues which prevent the air force from going that route. Later I asked Brian about stealth satellites and then he took a listener question about the way space debris was portrayed in the movie Gravity.  We spent some time discussing the impact of a movie like Gravity on the public regarding the space debris issue. As the program was ending, Brian said he was not that optimistic about a replacement fence and brought to our attention the need to upgrade computer systems that process the data.  As you will hear, this is a substantial problem that is not being addressed.

Please post comments/questions on The Space Show blog.  You can reach Brian through me or SWF.


1. lroimages - October 30, 2013

Thanks for the interesting show. Its too bad about losing the fence.

I have wondered about how they track items in space. I have access to space-track.org TLEs and use them with Satellite Toolkit. Although they obviously can track dropped items by ISS or Shuttle astronauts (which are relatively small), for some reason, ice of similar size is not tracked. Ice is shed off rockets, even in orbit, as well as from waste or other sources at ISS. I would have thought ice should be tracked because it can come in at high velocities too and cause damage to another spacecraft. Is ice invisible to tracking or do they just assume it will sublimate?

I am curious about meteorites. For some reason, the space-track.org database ONLY lists items that can be correlated to a launch. Surely there are meteoroids that, if only transiently, orbit the Earth. These seem to be included in the UCTs (uncorrelated targets). We have no visibility into how big these UCTs are or their inclinations or how many there are, or any information about them. It would be nice to have this data. Even small meteoroids would be of interest, since a spacecraft could be designed to collect them.

Does the whole process of the fence implies there are spots in space where no data is collected? Obviously, a suborbital ballistic trajectory over China or Iran does not show up in space-track.org TLEs. A fence implies the object must pass through it on an orbital trajectory. Thus, trajectories like the Chelyabinsk meteor’s would not be picked up. Is this true? In other words, take an object coming from directly above a point in the US at the Moon’s distance (but outside the space fence beam) and approaches to hit the ground (sort of an hyperbolic trajectory). It would miss being tracked, right? We don’t have 100% coverage of the sky over the U.S. up to and even beyond GEO, right?

The Chinese recently launched a vehicle to capture another (
http://gizmodo.com/why-is-china-testing-satellite-hijacking-space-weapons-1440744006). Has anyone confirmed that they even got close to the test capture? Using the basic space-track.org data shows they never got closer than 1.7 km (maybe within picture taking range). Others have claimed (in the freebeacon.com link in the article listed here), using this data, they did capture and release it. I thought the error band on those TLEs was not so large so that there was no way they touched.

Also, any idea why there would be bad TLEs. I have found TLEs associated with a vehicle prior to its launch. I have found a docked ISS and Shuttle with oddly different TLEs. How reliable are these TLEs?

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