* The sneak peek of the animated presentation can be viewed here (Its full copy available upon request).
In 2014, the US Missile Defense Agency (MDA), a section of the US Department of Defense (DoD), ambitiously launched its Space-based Kill Assessment (SKA) project in an effort to reinforce the American missile defense capabilities, such as the Ballistic Missile Defense System (BMDS), by 2020. The SKA sensors – an important component of the system to create a more robust communications network for more strategic interception of incoming threats – are expected to be on orbit in 2018, tested and fielded in the consecutive years. It is also noteworthy that these sensors will be piggy-backed on commercial satellites mainly for the cost savings benefits. This reportedly first partnership of the MDA with commercial stakeholders for its space applications evokes the on-going debate over the dual-use objects as a potential aid to space weapons, in addition to the implications of the ‘Military-Industrial Complex’ (MIC) associated with the US military.
While some governments, such as that of the US, insist on the self-defense and security purposes in its march towards outer space for military interests, like the justification of experimenting the US’ SKA sensor network, such military-oriented space policies have critically been assessed because they would eventually result in compromising the peaceful uses of outer space, as stipulated in the Outer Space Treaty (1967), by adding new tensions and sources of conflicts. A dilemma between the national security needs and the benefit of global cooperation never seems to end. Though, given the winds of war still blowing in our world, the current global paradigm calls for individual State’s voluntary dedication to the prevention of armed conflicts.
By and large, outer space is perceived as a field of adventure and unlimited possibilities; e.g., the mine of untouched natural resources and the next destination for civilization. And yet, it has also been serving as an excellent high ground from which to gain a military advantage since the inception of the Space Age, which may well generate some destructive outcomes contrary to such life-giving potentials publicly anticipated from 'space.' Thus, this presentation intends not only to discuss primarily how the US Space Program – as part of its national defense policy – is in conformity with an international effort to ‘harmoniously’ enhance global space security, but more importantly, to emphasize that now may be the time to reflect on the weight of our terrestrial decisions – government and industry alike – extending to the extraterrestrial forum. So, we may hopefully find a way to "bring space down to earth" truly for more sustainable human future, and ultimately, for the greater good of all people.
The combustion of metal suspensions occupies an important place in modern technology, such as propulsion or chemical safety. Metals have even been proposed as a possible carbon-free energy carrier as well as a propellant for in-situ production on the Moon or on Mars. It has been discovered that for a given field of parameters, the heterogeneous flames exhibit an unusual behavior. The flame cease to propagate as continuous fronts and become dominated by discrete effects, leading to low-velocity percolation-like propagation. This phenomenon has been reported in other areas of science such as in self-propagating high-temperature synthesis (SHS), chemical kinetics, or biology; the study of discrete flames in metal suspensions may therefore be crucial in understanding front propagation in many of these systems. Due to particle settling and buoyancy-driven disruptions of the flame, both caused by gravity, a clear parametric study of discrete flames can only be realized in microgravity environments. This lead to the PERWAVES experiment, performed in a microgravity environment aboard the European Space Agency sounding rocket Maxus 9, launched on April 7th, 2017. The tests involved the propagation of flames of iron suspensions dispersed in oxygen/xenon gas. The particle concentration was varied and two different oxygen/xenon proportions, 20%/80% and 40%/60% respectively, were used. It was found that flames propagate at low average speed (~1 cm/s), insensitive to combustion time of individual particles, in agreement with discrete regime predictions.
