The effects of stellar winds on the magnetospheres and potential habitability of exoplanets

Context: The principle definition of habitability for exoplanets is whether they can sustain liquid water on their surfaces, i.e. that they orbit within the habitable zone. However, the planet's magnetosphere should also be considered, since without it, an exoplanet's atmosphere may be eroded away by stellar winds. Aims: The aim of this paper is to investigate magnetospheric protection of a planet from the effects of stellar winds from solar-mass stars. Methods: We study hypothetical Earth-like exoplanets orbiting in the host star's habitable zone for a sample of 124 solar-mass stars. These are targets that have been observed by the Bcool collaboration. Using two wind models, we calculate the magnetospheric extent of each exoplanet. These wind models are computationally inexpensive and allow the community to quickly estimate the magnetospheric size of magnetised Earth-analogues orbiting cool stars. Results: Most of the simulated planets in our sample can maintain a magnetosphere of ~5 Earth radii or larger. This suggests that magnetised Earth analogues in the habitable zones of solar analogues are able to protect their atmospheres and is in contrast to planets around young active M dwarfs. In general, we find that Earth-analogues around solar-type stars, of age 1.5 Gyr or older, can maintain at least a Paleoarchean Earth sized magnetosphere. Our results indicate that planets around 0.6 - 0.8 solar-mass stars on the low activity side of the Vaughan-Preston gap are the optimum observing targets for habitable Earth analogues.Comment: 8 pages, 3 figures, accepted to Astronomy and Astrophysic

Language of Lullabies: The Russification and De-Russification of the Baltic States

This article argues that the laws for promotion of the national languages are a legitimate means for the Baltic states to establish their cultural independence from Russia and the former Soviet Union

Balance-of-Powers Arguments and the Structural Constitution

Balance-of-powers arguments are ubiquitous in judicial opinions and academic articles that address separation-of-powers disputes over the president\u27s removal authority, power to disregard statutes, authority to conduct foreign wars, and much else. However, the concept of the balance of powers has never received a satisfactory theoretical treatment. This Essay examines possible theories of the balance of powers and rejects them all as unworkable and normatively questionable. Judges and scholars should abandon the balance-of-powers metaphor and instead address directly whether bureaucratic innovation is likely to improve policy outcomes

Climate Change Meets the Law of the Horse

The climate change policy debate has only recently turned its full attention to adaptation - how to address the impacts of climate change we have already begun to experience and that will likely increase over time. Legal scholars have in turn begun to explore how the many different fields of law will and should respond. During this nascent period, one overarching question has gone unexamined: how will the legal system as a whole organize around climate change adaptation? Will a new distinct field of climate change adaptation law and policy emerge, or will legal institutions simply work away at the problem through unrelated, duly self-contained fields, as in the famous Law of the Horse? This Article is the first to examine that question comprehensively, to move beyond thinking about the law and climate change adaptation to consider the law of climate change adaptation. Part I of the Article lays out our methodological premises and approach. Using a model we call Stationarity Assessment, Part I explores how legal fields are structured and sustained based on assumptions about the variability of natural, social, and economic conditions, and how disruptions to that regime of variability can lead to the emergence of new fields of law and policy. Case studies of environmental law and environmental justice demonstrate the model’s predictive power for the formation of new distinct legal regimes. Part II applies the Stationarity Assessment model to the topic of climate change adaptation, using a case study of a hypothetical coastal region and the potential for climate change impacts to disrupt relevant legal doctrines and institutions. We find that most fields of law appear capable of adapting effectively to climate change. In other words, without some active intervention, we expect the law and policy of climate change adaptation to follow the path of the Law of the Horse - a collection of fields independently adapting to climate change - rather than organically coalescing into a new distinct field. Part III explores why, notwithstanding this conclusion, it may still be desirable to seek a different trajectory. Focusing on the likelihood of systemic adaptation decisions with perverse, harmful results, we identify the potential benefits offered by intervening to shape a new and distinct field of climate change adaptation law and policy. Part IV then identifies the contours of such a field, exploring the distinct purposes of reducing vulnerability, ensuring resiliency, and safeguarding equity. These features provide the normative policy components for a law of climate change adaptation that would be more than just a Law of the Horse. This new field would not replace or supplant any existing field, however, as environmental law did with regard to nuisance law, and it would not be dominated by substantive doctrine. Rather, like the field of environmental justice, this new legal regime would serve as a holistic overlay across other fields to ensure more efficient, effective, and just climate change adaptation solutions

Theology in Public Reason and Legal Discourse: A Case for the Preferential Option for the Poor

There is a strange disconnect between the formal understanding of the separation of religion from government in the United States and the almost ubiquitous use of religious language in political discourse, not to mention the web of complicated religious motivations that sit on or just below the surface of policy debates. This paper presents an argument for the relevance of the principle of the preferential option for the poor from Catholic social thought in public reason and legal discourse in order to explore the possible advantages of making the veil between religion and the secular state more permeable. As a case study, it proposes dialogue between Catholicism and complementary secular thought, including standpoint theory, outsider methodology, and law and economics to explore possibilities for more effectively ensuring justice for the poor and marginalized