Wine and Cheese Spring 2026: Difference between revisions
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'''Astronomy on the Hill: Federal Funding and Dark & Quiet Skies Policy'''<br> | '''Astronomy on the Hill: Federal Funding and Dark & Quiet Skies Policy'''<br> | ||
The landscape of federal science policy has shifted dramatically over the past year. As the FY2026 federal funding cycle concludes, this talk will provide a brief overview of the current fiscal situation for the astronomical sciences, as well as an outlook for FY2027 and beyond. We will then examine the Dark & Quiet Skies initiative, a global effort to preserve the night sky from light pollution and radio frequency interference from satellites. We will review recent regulatory developments in the space environment and highlight how the astronomical community works with commercial space operators and the federal government to ensure a sustainable orbital environment. The talk concludes with a discussion of how scientists at all career stages can engage with policymakers to ensure astronomy and science remains a priority on Capitol Hill. | The landscape of federal science policy has shifted dramatically over the past year. As the FY2026 federal funding cycle concludes, this talk will provide a brief overview of the current fiscal situation for the astronomical sciences, as well as an outlook for FY2027 and beyond. We will then examine the Dark & Quiet Skies initiative, a global effort to preserve the night sky from light pollution and radio frequency interference from satellites. We will review recent regulatory developments in the space environment and highlight how the astronomical community works with commercial space operators and the federal government to ensure a sustainable orbital environment. The talk concludes with a discussion of how scientists at all career stages can engage with policymakers to ensure astronomy and science remains a priority on Capitol Hill. | ||
=09 February= | |||
==Chris Nagele (JHU)== | |||
'''Radiation Transfer Simulations of Black Hole Spectra'''<br> | |||
Spectra from accreting black holes are one of our most powerful tools for understanding these enigmatic objects. These spectra, however, are not well understood. For example, stellar mass black holes and supermassive black holes exhibit different spectral properties, with the stellar mass black holes changing between different spectral states (hard and soft states) while the supermassive black holes have more uniform spectral slopes. We run radiation transfer post-processing of general relativistic magnetohydrodynamical simulations of black hole accretion, in order to generate spectral predictions. We use two radiation transfer codes, Pandurata and PTransX, to solve for thermal balance and ionization balance in different parts of the simulation. Our spectra are remarkably similar to observed trends, with a clear hard/soft dependence on accretion rate at M = 10 Msun and uniformly flat spectra in the supermassive regime. We also compute high resolution spectra in order to simulate emission lines coming from the accretion disk near the black hole. Our spectra contain Fe Kalpha lines with equivalent widths (50-200 eV) and line shapes consistent with observations. We find, however, that the breadth of these lines is due to several factors, and not simply to extreme relativistic motions near the black hole, as is almost always assumed. We discuss how physical quantities from our simulations can be incorporated into models which perform black hole parameter inference, thereby breaking some of the degeneracy associated with these models. | |||
==Stephen Schmidt (JHU)== | |||
'''Hot Jupiters are Inflated Primarily by Shallow Heating'''<br> | |||
The unexpectedly large radii of transiting hot Jupiters have led to many proposals for the physical mechanisms responsible for heating their interiors. While it has been shown that hot Jupiters reinflate as their host stars brighten due to heating deep in planetary interiors, young hot Jupiters also exhibit signs of delayed cooling possibly related to heating closer to their surfaces. To investigate this tension, we enhance our previously published hot Jupiter thermal evolution model by adding a parameter that allows for both deep heating and delayed cooling. We fit our thermal evolution models to a homogeneous, physically self-consistent catalog of accurate and precise hot Jupiter system properties in a hierarchical Bayesian framework. We find that hot Jupiters' interior cooling rates are reduced on average by 95%--98% compared to simpler anomalous heating models. The most plausible explanation for this inference is substantial shallow heating just below their radiative--convective boundaries that enables reinflation with much less deep heating. Shallow heating by Ohmic dissipation and/or temperature advection are therefore important components of accurate models of hot Jupiter atmospheres, especially in circulation models. If hot Jupiters are inflated primarily by shallow heating as we propose, then we predict that their observed phase curve offsets should increase with temperature in the range T_eq <~ 1500 K, peak in the range 1500 K <~ T_eq <~ 1800 K, and decrease in the range T_eq >~ 1800 K. | |||
=016 February= | |||
==TBD== | |||
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=23 February= | |||
==TBD== | |||
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=02 March= | |||
==TBD== | |||
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=09 March= | |||
==TBD== | |||
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=23 March= | |||
==TBD== | |||
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=30 March= | |||
==TBD== | |||
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=06 April= | |||
==TBD== | |||
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=13 April= | |||
==TBD== | |||
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=20 April= | |||
==TBD== | |||
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=27 April= | |||
==TBD== | |||
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=04 May= | |||
==TBD== | |||
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Revision as of 17:49, 3 February 2026
This page records the schedule, titles and abstracts of the JHU/STScI CAS Astrophysics Wine & Cheese Series in Spring 2026.
Wine and Cheese sessions with one speaker will have a 50 minute talk with 10 minutes for questions. Sessions with two speakers will have two 25 minute talks, each with 5 minutes for questions.
Back to W&C Schedule
26 January
Colin Hamill (AAS)
Astronomy on the Hill: Federal Funding and Dark & Quiet Skies Policy
The landscape of federal science policy has shifted dramatically over the past year. As the FY2026 federal funding cycle concludes, this talk will provide a brief overview of the current fiscal situation for the astronomical sciences, as well as an outlook for FY2027 and beyond. We will then examine the Dark & Quiet Skies initiative, a global effort to preserve the night sky from light pollution and radio frequency interference from satellites. We will review recent regulatory developments in the space environment and highlight how the astronomical community works with commercial space operators and the federal government to ensure a sustainable orbital environment. The talk concludes with a discussion of how scientists at all career stages can engage with policymakers to ensure astronomy and science remains a priority on Capitol Hill.
09 February
Chris Nagele (JHU)
Radiation Transfer Simulations of Black Hole Spectra
Spectra from accreting black holes are one of our most powerful tools for understanding these enigmatic objects. These spectra, however, are not well understood. For example, stellar mass black holes and supermassive black holes exhibit different spectral properties, with the stellar mass black holes changing between different spectral states (hard and soft states) while the supermassive black holes have more uniform spectral slopes. We run radiation transfer post-processing of general relativistic magnetohydrodynamical simulations of black hole accretion, in order to generate spectral predictions. We use two radiation transfer codes, Pandurata and PTransX, to solve for thermal balance and ionization balance in different parts of the simulation. Our spectra are remarkably similar to observed trends, with a clear hard/soft dependence on accretion rate at M = 10 Msun and uniformly flat spectra in the supermassive regime. We also compute high resolution spectra in order to simulate emission lines coming from the accretion disk near the black hole. Our spectra contain Fe Kalpha lines with equivalent widths (50-200 eV) and line shapes consistent with observations. We find, however, that the breadth of these lines is due to several factors, and not simply to extreme relativistic motions near the black hole, as is almost always assumed. We discuss how physical quantities from our simulations can be incorporated into models which perform black hole parameter inference, thereby breaking some of the degeneracy associated with these models.
Stephen Schmidt (JHU)
Hot Jupiters are Inflated Primarily by Shallow Heating
The unexpectedly large radii of transiting hot Jupiters have led to many proposals for the physical mechanisms responsible for heating their interiors. While it has been shown that hot Jupiters reinflate as their host stars brighten due to heating deep in planetary interiors, young hot Jupiters also exhibit signs of delayed cooling possibly related to heating closer to their surfaces. To investigate this tension, we enhance our previously published hot Jupiter thermal evolution model by adding a parameter that allows for both deep heating and delayed cooling. We fit our thermal evolution models to a homogeneous, physically self-consistent catalog of accurate and precise hot Jupiter system properties in a hierarchical Bayesian framework. We find that hot Jupiters' interior cooling rates are reduced on average by 95%--98% compared to simpler anomalous heating models. The most plausible explanation for this inference is substantial shallow heating just below their radiative--convective boundaries that enables reinflation with much less deep heating. Shallow heating by Ohmic dissipation and/or temperature advection are therefore important components of accurate models of hot Jupiter atmospheres, especially in circulation models. If hot Jupiters are inflated primarily by shallow heating as we propose, then we predict that their observed phase curve offsets should increase with temperature in the range T_eq <~ 1500 K, peak in the range 1500 K <~ T_eq <~ 1800 K, and decrease in the range T_eq >~ 1800 K.
016 February
TBD
Title
Abstract
23 February
TBD
Title
Abstract
02 March
TBD
Title
Abstract
09 March
TBD
Title
Abstract
23 March
TBD
Title
Abstract
30 March
TBD
Title
Abstract
06 April
TBD
Title
Abstract
13 April
TBD
Title
Abstract
20 April
TBD
Title
Abstract
27 April
TBD
Title
Abstract
04 May
TBD
Title
Abstract
