College of Arts and Sciences

The Universe, Magnified: The Power of Gravitational Lensing
Keren Sharon (Michigan)
When did the Universe form its first galaxies? What do galaxies look like at the epoch when the Universe formed most of its stars? Some of the answers to those questions (and others) await a new generation of large ground and space based telescopes. In the meanwhile, strong gravitational lensing has become a useful tool to boost the power of present day telescopes, enabling detailed studies of galaxies that are otherwise either too dim or have too small of an angular size on the sky. 

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Ocean Worlds: from Familiar to Exotic and Extreme Planets
Dimitar Sasselov (Harvard)
Water is a common molecule in the the galaxy and an abundant bulk component of planets – like Neptune, far from their stars. Liquid water – a precious solvent,  might be significantly more rare. Exoplanet exploration is both motivated by the search for surface liquid water and is helping us understand the wide diversity of ocean worlds. Such understanding is necessary if we are to succeed in the search for planetary conditions that could lead to the emergence of life.

(Note special day and time)

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Our Goals for Lunar Science and Exploration
Brett Denevi (JHU/APL)

NASA has recently announced plans to refocus its attention on the Moon as a cornerstone for Solar System science and exploration. However, similar announcements were made in the not-so-distant past, only to be cancelled before they could come to fruition. What have we learned along the way? And what can we learn from new orbital and landed missions to the Moon? I will present recent highlights in lunar science, the highest priority lunar science goals as determined by the National Research Council, and some of the ways we will seek to answer those questions.

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The Universe’s Most Extreme Star-Forming Galaxies in the Most Extreme Environments
Caitlin Casey (Texas)

Dusty star-forming galaxies host the most intense stellar nurseries in the Universe. Their unusual characteristics (star formation rates of 200-2000 Msun/yr, compared to the Milky Way’s 1 Msun/yr) pose a unique challenge for cosmological simulations of how galaxies form and evolve, particularly in the first few billion years after the Big Bang. Although rare today, these unusual galaxies were factors of 1000 times more prevalent 10 billion years ago, contributing significantly to the buildup of the Universe’s stars during catastrophic galaxy-galaxy collisions that ignited shortlived but extremely powerful bursts of star formation.

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Data Science: The what, why, and how of my transition from Science to Tech
Cameron McBride (Rubicon Project)

Data science continues to explode as a field as the industrial need for scientific rigor grows. It can be referred to by many names: machine learning, artificial intelligence, statistics, science, or sometimes even software engineering. I trained to be an academic scientist, and did research in extragalactic astronomy and cosmology across four major research institutions and as part of an international collaboration. Over the past three years, I have worked for two startups and a larger corporation solving challenging problems across two fields.

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Title: The hunt for cosmic monsters: understanding galaxies in the confused FIR sky
Jillian Scudder (Oberlin)

Observing galaxies in the Far-Infrared (FIR) gives us a unique window into the star formation rates of very high redshift, dusty galaxies. These galaxies are generally thought to be forming stars at a prodigious rate, heating their dust within their host galaxy, which then radiates in the FIR. However, observing this luminous dust is difficult, even with a space-based telescope such as the Herschel Space Observatory, as the resolution of the images returned is quite poor. It is often assumed that a bright source in the FIR belongs to a single,

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Simulating Galaxy Formation: IllustrisTNG and beyond
Mark Vogelsberger (MIT)

In my talk I will describe recent efforts to model the large-scale distribution of galaxies with cosmological hydrodynamics simulations. I will focus on the Illustris simulation, and our new simulation campaign, the IllustrisTNG project. After demonstrating the success of these simulations in terms of reproducing an enormous amount of observational data, I will also talk about directions for further improvements over the next couple of years.

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hWAET: a ground-based telescope for exoplanet direct imaging
Ben Monreal (CWRU Physics)

In the literature on telescope conceptual design, there is a divide which at first glance seems unusual: space telescope design is a free-for-all while ground based concepts are very conservative. As an instrument-builder, although most of my work is on neutrinos and dark matter I am also wading into the understudied edges of ground-based telescope design. In this talk, I will introduce WAET, a new (but still fairly conservative) construction concept for large ground-based optical/IR telescopes. WAET is intended to use conventional components and prescriptions to get to huge apertures at extremely low cost.

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Stars Re-Shaping Galaxies
Phil Hopkins (Caltech)

The most fundamental unsolved problems in galaxy formation revolve around “feedback” from massive stars and black holes. I’ll present new results from the FIRE simulations which combine new numerical methods and physics in an attempt to realistically model the diverse physics of the interstellar medium, star formation, and feedback from stellar radiation pressure, supernovae, stellar winds, and photo-ionization. These mechanisms lead to ‘self-regulated’ galaxy and star formation, in which global correlations such as the Schmidt-Kennicutt law and the global inefficiency of star formation — the stellar mass function —

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The Puzzle of Boyajian’s Star
Jason Wright (PSU)

I have been at the center of efforts to understand KIC 8462852, a strange star found during the Kepler mission. It exhibits deep, irregular “dips” or dimming events lasting days, up to 22% in depth, and appears to be dimming secularly on decadal timescales. As ever-more-contrived natural explanations are proposed and explored by my team and others, we continue to put together monitoring and target-of-opportunity programs to catch it “in the act” of dipping and determine the nature of the dips. I will discuss the families of possible solutions for this star,

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NOAO Today and Tomorrow
David Silva (Director, NOAO)

The National Optical Astronomy Observatory (NOAO) is the U.S. national center for ground-based optical-infrared (OIR) astronomy. It is a Federally Funded Research and Development Center (FFRDC) sponsored by the National Science Foundation (NSF) and managed by the Association of Universities for Research in Astronomy (AURA). The NOAO mission is to enable discovery for the research community-at-large through open access to world-class facilities, capabilities, services, and data products. At NSF request, AURA is developing a plan to create the National Center for OIR Astronomy (NCOA) by restructuring the Gemini Observatory,

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Twinkle, twinkle, little galaxy
Annika Peter (OSU)

The littlest galaxies have the potential to tell us the most about the nature of dark matter and about star formation in extreme environments. In this talk, I describe what they are telling us already, what the open questions are, and my approach to answering them. I will highlight new opportunities with the next generation of astronomical surveys.

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Opening New Frontiers in the Study of Star Formation with the Next Generation of Radio Telescopes
Amanda Kepley (NRAO)
Much of what we know about the molecular gas that fuels star formation comes from observations in the Milky Way and other similar nearby galaxies. This sample only probes a relatively narrow range of galaxy properties and thus does not provide an effective test of how galaxy properties like mass, metallicity, and star formation rate affect star formation. With the advent of new instruments like Atacama Large Millimeter/submillimeter Array (ALMA), the Green Bank Telescope (GBT), and the Jansky Very Large Array (JVLA),

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