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US Official: 2013 Budget Targets Space Capability Resilience
defpro … Shelton said, “invests in programs that enhance the resiliency and effectiveness of our space capabilities, namely missile warning, positioning, navigation and timing, satellite communications, space situational awareness and space launch. |
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2013 Budget Targets Space Capability Resilience
Department of Defense … Shelton said, “invests in programs that enhance the resiliency and effectiveness of our space capabilities, namely missile warning, positioning, navigation and timing, satellite communications, space situational awareness and space launch. |
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2013 Budget Targets Space Capability Resilience
Department of Defense … Shelton said, “invests in programs that enhance the resiliency and effectiveness of our space capabilities, namely missile warning, positioning, navigation and timing, satellite communications, space situational awareness and space launch. |
The development of an effective space surveillance network requires the creation of an comprehensive, accurate and trustworthy catalogue of objects in orbit. This forms the basis for the multitude of services such as conjunction prediction and re-entry warning are expected.
By comprehensive, the system must be able to those objects which may pose a threat to operational satellites. This means that they should be able to detect objects with a minimum diameter to cause a detectable or cumulative deterioration in the performance of a satellite. This minimum diameter is defined by both the kintetic energy contained within a piece of debris (related to the mass and velocity) and the probability that a satellite will be operationally damaged by the impact of such a piece of debris.
As with the diameter of an object, the accuracy that will be achieved is limted by numerous factors, these include the limits of the technology used, the number of sensors within the surveillance network and the observation conditions (at both sensor and target) when detecting a specific piece of debris.
When discussing the degree to which a system can be considered trustworthy, three main factors come into play. These are the degree of false readings created by a sensors, the method used to convert the detections into an orbit and the techniques used to relate individual detected passes to objects which already exist in the database. These are all affected by the way in which the sensor system is designed, the weighting or importance given to specific sensors and the actual technology employed when looking at orbiting debris.
In order to develop a system which provides the needed performance, as well as being economically viable, requires a careful monitoring of the interplay between the multiple factors which determine the final design. This is the purpose of the top-down stream of ESA SSA programme and development. Not an easy task – and there are no absolute answers – but in the area of complex system-of-system design, the Agency has a long history of successful and effective solutions.
When satellite imaging is mentioned, we usually think of satellites taking pictures of the weather, floods or downtown New York. This is one of the primary uses of satellites and one which has brought great benefits to many people. Within space surveillance, satellite imaging refers to taking pictures of satellites on orbit. But why would we want to do that?
One reason is when things don’t go as planned. Satellite operators cannot always see what is happening on the satellite directly, but rely on specific sensors to tell them if something has – or hasn’t – worked. This could be a signal to say that the solar panels have been set correctly. If this signal hasn’t been received, it could mean one of two things. Either the solar panel hasn’t been set correctly or the sensor has malfunctioned. But which one of the two is it? Sometimes this specific situation can be verified because there is no power being generated by the solar panel or the satellite’s attitude moves in such a way that indicates the solar panel is not sticking out of the side of the satellite body. In either case, an independant way to verify this would be useful.
Another reason is during re-entry. The way a space object is oriented can effect large changes in the re-entry profile. It can determine if the satellite will break up high in the atmosphere and these small pieces vapourise without touching the Earth’s surface or if the orientation will cause some drag or lift as it comes through the atmopshere and hence change the impact point. Being able to image an object as it comes close to re-entry and begins to be affected by the atmosphere can really help reduce the uncertainty in both these areas.
A final reason why satellite imaging is important is – as can be guessed – military. Having intelligence regarding the capabilities of satellites in orbit is very useful to military commanders. Using satellite imaging could be a good way to do this.
Of course any specific military requirments are out of the scope of the ESA SSA programme. It can be predicted that the resolution required to perform the first two functions of anomaly resolution and re-entry prediction is much less than that required for the third one.
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Biggest solar shot since 1995 is Earth-bound
Network World Moreover, the number of long-lived, 10 cm and larger debris appears to have been only a few dozen. NASA said only three standard satellite breakups were detected by the US Space Surveillance Network during the year. |
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Fourth Wideband Global SATCOM Satellite Set to Launch
Space Ref (press release) … military satellite communications, defense meteorological satellites, space launch and range systems, satellite control network, space based infrared systems, intercontinental ballistic missile systems and space situational awareness capabilities. |
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UK space surveillance system takes birthday snap of only satellite ever …
Space Daily In celebration of this anniversary, space scientists at UCL are attempting to re-establish contact with Prospero and UK space surveillance company Space Insight has captured a new image of the satellite. This new image was taken just a month after … |
 The Guardian |
Space debris collisions a growing risk, experts warn
The Guardian In a presentation he made to the European space surveillance conference in Madrid in June, Stevens said: "Increased collision activity is likely to result in increased litigation … [and is] likely to be a driver for satellite manufacturers and launch … |
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Astro Trash: A Cage of Our Own Device
Big Think … stake holders such as satellite operators, insurers, military, governmental space agencies, and other groups working on issues such as space situational awareness, space weather, air traffic control and collision avoidance devices and techniques. … |