The hot Jupiter period-mass distribution as a signature of in situ formation

More than two decades after the widespread detection of Jovian-class planets on short-period orbits around other stars, their dynamical origins remain imperfectly understood. In the traditional narrative, these highly irradiated giant planets, like Jupiter and Saturn, are envisioned to have formed at large stello-centric distances and to have subsequently undergone large-scale orbital decay. Conversely, more recent models propose that a large fraction of hot Jupiters could have formed via rapid gas accretion in their current orbital neighborhood. In this study, we examine the period-mass distribution of close-in giant planets, and demonstrate that the inner boundary of this population conforms to the expectations of the in-situ formation scenario. Specifically, we show that if conglomeration unfolds close to the disk's inner edge, the semi-major axis - mass relation of the emergent planets should follow a power law $a \propto M^{-2/7}$ - a trend clearly reflected in the data. We further discuss corrections to this relationship due to tidal decay of planetary orbits. Although our findings do not discount orbital migration as an active physical process, they suggest that the characteristic range of orbital migration experienced by giant planets is limited.Comment: 5 pages, 1 figure, accepted in ApJ

Solar Obliquity Induced by Planet Nine

The six-degree obliquity of the sun suggests that either an asymmetry was present in the solar system's formation environment, or an external torque has misaligned the angular momentum vectors of the sun and the planets. However, the exact origin of this obliquity remains an open question. Batygin & Brown (2016) have recently shown that the physical alignment of distant Kuiper Belt orbits can be explained by a 5-20 Earth-mass planet on a distant, eccentric, and inclined orbit, with an approximate perihelion distance of ~250 AU. Using an analytic model for secular interactions between Planet Nine and the remaining giant planets, here we show that a planet with similar parameters can naturally generate the observed obliquity as well as the specific pole position of the sun's spin axis, from a nearly aligned initial state. Thus, Planet Nine offers a testable explanation for the otherwise mysterious spin-orbit misalignment of the solar system.Comment: 8 pages, 4 figures, manuscript #: AAS01477, submitted on June 24, 201

Feasibility of a resonance-based Planet Nine search

It has been proposed that mean motion resonances (MMRs) between Planet Nine and distant objects of the scattered disk might inform the semimajor axis and instantaneous position of Planet Nine. Within the context of this hypothesis, the specific distribution of occupied MMRs largely determines the available constraints. Here we characterize the behavior of scattered Kuiper Belt objects arising in the presence of an eccentric Planet Nine ($e_9 \in 0.1$, $0.7$), focusing on relative sizes of populations occupying particular commensurabilities. Highlighting the challenge of predicting the exact MMR of a given object, we find that the majority of resonant test particles have period ratios with Planet Nine other than those of the form $P_9/P=N/1$, $N/2$ $(N \in \mathbb{Z}^+)$. Taking into account the updated prior distribution of MMRs outlined in this work, we find that the close spacing of high-order resonances, as well as chaotic transport, preclude resonance-based Planet Nine constraints from current observational data.Comment: 6 pages, 7 figure

Software quality assurance plan for GCS

The software quality assurance (SQA) function for the Guidance and Control Software (GCS) project which is part of a software error studies research program is described. The SQA plan outlines all of the procedures, controls, and audits to be carried out by the SQA organization to ensure adherence to the policies, procedures, and standards for the GCS project

Constructing A Well-Being: Exploring Knowledge Construction In Dbt Skills Training Using Art And Activity Theory

Through Arts-based Research, constructed within the theoretical basis of the Activity System, participants engaged with dialectical behavior therapy (DBT) program content to develop a cohesive and meaningful project. Participants are conceptualized as reliable experts in their own experience, and as active agents of knowledge construction. Participants generate profound and relevant insights into their experiences – insights that can enhance DBT practice, expand research methodology, and build conceptual connections across theories. The Arts-based Activity System offers a theoretically-backed methodology that can disrupt the harmful parallels between the development of the disorders DBT is intended to treat and the dominant research paradigm into DBT. In this paradigm shift, participants are regarded as empowered to construct their wellness by leveraging the tools and settings of DBT, rather than as passive objects of research and recipients of care. Additionally, this study constructs an argument for the use of Arts-Based Activity Theory as a research methodology to investigate social knowledge construction in communities whose knowledge construction may be otherwise be unavailable to researchers. Finally, this study builds a conceptual connection between the Reflective Practitioner Theory and Activity Theory by contextualizing participant reflections as parts of an Activity System

Allowance trading activity and state regulatory rulings : evidence from the U.S. Acid Rain Program

The U.S. Acid Rain Program is one of the first, and by far the most extensive, applications of a market based approach to pollution control. From the beginning, there has been concern whether utilities would participate in allowance trading, and whether regulatory activity at the state level would further complicate utilities' decision to trade allowances. This paper finds that public utility commission regulation has encouraged allowance trading activity in states with regulatory rulings, but that allowance trading activity has not been limited to states issuing regulations. Until there is evidence suggesting that significant additional cost savings could have been obtained if additional allowance trading activity had occurred in states without regulations or that utilities in states with regulations are still not taking advantage of all cost saving trading opportunities, this analysis suggests that there is little reason to believe that allowance trading activity is impeded by public utility commission regulations

Allowance trading activity and state regulatory rulings : evidence from the U.S. Acid Rain Program

The U.S. Acid Rain Program is one of the first, and by far the most extensive, applications of a market based approach to pollution control. From the beginning, there has been concern whether utilities would participate in allowance trading, and whether regulatory activity at the state level would further complicate utilities' decision to trade allowances. This paper finds that public utility commission regulation has encouraged allowance trading activity in states with regulatory rulings, but that allowance trading activity has not been limited to states issuing regulations. Until there is evidence suggesting that significant additional cost savings could have been obtained if additional allowance trading activity had occurred in states without regulations or that utilities in states with regulations are still not taking advantage of all cost saving trading opportunities, this analysis suggests that there is little reason to believe that allowance trading activity is impeded by public utility commission regulations.Supported by a grant from the National Acidic Precipitation Assessment Program (NAPAP) and by a National Science Foundation Graduate Research Fellowship