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Beech M.,Campion College at the University of Regina
Astrophysics and Space Science | Year: 2011

A brief review of the threat posed to Earth's biosphere via near-by supernova detonations is presented. The expected radiation dosage, cosmic ray flux and expanding blast wave collision effects are considered, and it is argued that a typical supernova must be closer than ~10-pc before any appreciable and potentially harmful atmosphere/biosphere effects are likely to occur. In contrast, the critical distance for Gamma-ray bursts is of order 1-kpc. In spite of the high energy effects potentially involved, the geological record provides no clear-cut evidence for any historic supernova induced mass extinctions and/or strong climate change episodes. This, however, is mostly a reflection of their being numerous possible (terrestrial and astronomical) forcing mechanisms acting upon the biosphere and the difficulty of distinguishing between competing scenarios. Key to resolving this situation, it is suggested, is the development of supernova specific extinction and climate change linked ecological models. Moving to the future, we estimate that over the remaining lifetime of the biosphere (~2 Gyr) the Earth might experience 1 GRB and 20 supernova detonations within their respective harmful threat ranges. There are currently at least 12 potential pre-supernova systems within 1-kpc of the Sun. Of these systems IK Pegasi is the closest Type Ia pre-supernova candidate and Betelgeuse is the closest potential Type II supernova candidate. We review in some detail the past, present and future behavior of these two systems. Developing a detailed evolutionary model we find that IK Pegasi will likely not detonate until some 1.9 billion years hence, and that it affords absolutely no threat to Earth's biosphere. Betelgeuse is the closest, reasonably well understood, pre-supernova candidate to the Sun at the present epoch, and may undergo detonation any time within the next several million years. The stand-off distance of Betelgeuse at the time of its detonation is estimated to fall between 150 and 300-pc-again, affording no possible threat to Earth's biosphere. Temporally, the next most likely, close, potential Type Ic supernova to the Sun is the Wolf-Rayet star within the γ2 Velorum binary system located at least 260-pc away. It is suggested that evidence relating to large-scale astroengineering projects might fruitfully be looked for in those regions located within 10 to 30-pc of any pre-supernova candidate system. © 2011 Springer Science+Business Media B.V.


Beech M.,Campion College at the University of Regina
Observatory | Year: 2011

A brief overview of the α Centauri system is presented and the possibility that planets and a cometary can be formed about α Cen AB is considered. The rotational and flare-activity characteristics of Proxima Centauri is also reviewed. The impact hypothesis is revisited to determine if the flare activity associated with Proxima will be explained or modulated through planetesimal accretion. The use of Oort Cloud characteristics as an analogue reveals that the impact rate on Proxima is low to account for its overall flare activity. It is also revealed that the Proxima needs to reside just 15000 AU from α Cen AB, while the possibility of such an arrangement coming about purely by chance are about I in 57000.


Beech M.,Campion College at the University of Regina
Astronomy and Geophysics | Year: 2012

Martin Beech looks at the history of scientific interest in our nearest star system, ± Centauri, and the recent surge in research that has resulted in the discovery of our nearest exoplanet. © 2012 Royal Astronomical Society.


Beech M.,Campion College at the University of Regina
Monthly Notices of the Royal Astronomical Society | Year: 2010

We investigate the heating of micrometeorites and dust particles, as they decelerate in the Earth's upper atmosphere, when finite-size correction effects to the Stefan-Boltzmann surface reradiation law apply. For particles smaller than about 25 μm across, it is found that the finite-size corrections result in significantly lower maximum temperatures being realized. Indeed, the finite-size correction to the Stefan-Boltzmann law acts in the opposite sense to that of a reduced radiative efficiency which tends to increase the temperature of small meteoroids. It is also found that the accumulated thermal processing during atmospheric deceleration is greatly reduced when finite-size correction effects become important and this may have important consequences for the loss of volatile elements, as well as any petrographic alterations that a dust particle may experience. © 2009 The Author. Journal compilation © 2009 RAS.


Beech M.,Campion College at the University of Regina | Coulson I.M.,University of Regina
Monthly Notices of the Royal Astronomical Society | Year: 2010

An analysis of the circumstances leading to the placement of the large iron meteorite, unofficially named Block Island, on Mars is presented. We investigate the possibility that Block Island fell during the late Noachian period on Mars when its atmosphere was much denser (and hence much more massive) than at the present time. Indeed, we find that in order to produce a non-crater-forming, non-fragmenting meteorite with the characteristics of Block Island, the surface pressure of the Martian atmosphere must have been at least one to two orders of magnitude larger than it is at the present epoch. © 2010 The Authors. Journal compilation © 2010 RAS.


Arbuthnott K.D.,Campion College at the University of Regina
Analyses of Social Issues and Public Policy | Year: 2010

Changing human behavior to support environmental sustainability will often require delaying gratification of consumptive goals. This article reviews findings from the delay of gratification and temporal discounting literatures, examining the implications of these results for environmental behavior-change goals and programs. Evidence indicates that the ability to delay gratification is strongly influenced by the salience and difficulty of immediate versus delayed goals, so context management is vital to facilitate long-term environmental goals. The influence of belief on long-term goal attainment and goal framing also suggests a role for targeting individual beliefs and skills in education programs. © 2010 The Society for the Psychological Study of Social Issues.


Arbuthnott K.D.,Campion College at the University of Regina
Analyses of Social Issues and Public Policy | Year: 2012

Markowitz and Bowerman's (2011) observation that a large majority of Oregon citizens support reduced consumption is heartening, and is a good basis for their suggestion that public policy be directed at the issue of consumption. However, evidence of weak correlations between self-reported intentions and observed behaviors indicates that reducing actual consumption will be effortful, despite favorable attitudes. Two particular barriers to the transition from attitude to action, habits, and psychological needs are discussed, and it is suggested that evidence of association between well-being and reduced consumption could provide more specific direction for public actions. © 2011 The Society for the Psychological Study of Social Issues.


Beech M.,Campion College at the University of Regina
Earth, Moon and Planets | Year: 2014

The origin of the Rio Cuarto crater field, Argentina has been widely debated since the early 1990s when it was first brought to public attention. In a binary on–off sense, however, the craters are either of a terrestrial origin or they formed via a large asteroid impact. While there are distinct arguments in favour of the former option being the correct interpretation, it is the latter possibility that is principally investigated here, and five distinct impact formation models are described. Of the impact scenarios it is found that the most workable model, although based upon a set of fine-tuned initial conditions, is that in which a large, 100–150-m initial diameter asteroid, entered Earth’s atmosphere on a shallow angle path that resulted in temporary capture. In this specific situation a multiple-thousand kilometer long flight path enables the asteroid to survive atmospheric passage, without suffering significant fragmentation, and to impact the ground as a largely coherent mass. Although the odds against such an impact occurring are extremely small, the crater field may nonetheless be interpreted as having potentially formed via a very low-angle, smaller than 5° to the horizon, impact with a ground contact speed of order 5 km/s. Under this scenario, as originally suggested by Schultz and Lianza (Nature 355:234, 1992), the largest of the craters (crater A) in the Rio Cuarto structure was produced in the initial ground impact, and the additional, smaller craters are interpreted as being formed through the down-range transport of decapitated impactor material and crater A ejecta. © 2014, Springer Science+Business Media Dordrecht.


Beech M.,Campion College at the University of Regina
Astrophysics and Space Science | Year: 2011

Possible orbits for the motion of Proxima Centauri about α-Centauri A/B are derived according to standard Newtonian conditions and under the Modified Newtonian Dynamics (MOND) paradigm. Likely orbits are derived under the assumption that Proxima is coeval with α-Centauri A/B, located at, or very close to apastron, and that its radial velocity will ultimately be determined as being of order -22.15 km/s-bringing it closer to the observed radial velocity value for α-Centauri A/B. It is found under standard Newtonian conditions that Proxima might occupy an orbit described according to a semi-major axis and eccentricity of (a,e) = (8,500, 0.78)-resulting in an orbital period of some 53,500 years. If Proxima's motion is constrained to move entirely under weak-field MOND conditions then a provisional orbit having (a,e)=(12,527, 0.2) is obtained. In principle, we argue, by obtaining an ultra-precise value for the radial velocity of Proxima a distinction between the standard Newtonian gravity and the MOND orbital approximations can be made. © 2011 Springer Science+Business Media B.V.


Beech M.,Campion College at the University of Regina
Earth, Moon and Planets | Year: 2014

Simultaneous, also called electrophonic sounds were widely reported by eye-witnesses to the Chelyabinsk fireball. The available data indicate that such sounds were heard at ranges to at least ~100 km from the fireball’s atmospheric path. We estimate that the fireball may have generated of order 625 W of energy in the form of very low frequency radiation, and we find some tentative evidence to indicate that the acoustic conversion efficiency at a 100 km range was of order 0.1 %. Numerical simulations of the atmospheric flight path indicate that electrophonic sounds should have commenced some 5 s after the fireball first became luminous and would have lasted for some 7.5 s prior to the moment of catastrophic break-up. © 2014, Springer Science+Business Media Dordrecht.

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