Intro Talk ISM@ST Joshua E. G. Peek Associate Astronomer with Tenure Data Science Mission Office Project Scientist Barbara A. Mikulski Archive for Space Telescopes Principal Investigator Associate Research Scientist — Johns Hopkins University 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Murray, Peek et al 2018 Optically Thick H I Does Not Dominate Dark Gas in the Local ISM 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps 20 0 20 229 225 14 19 23 229 225 14 19 23 500 00 +500 +500 00 500 50 100 Tb [K] annel Map 0.5 w v sharp Mask 0.2 I857 acked I857 vlsr [km/s] Thin channels in HI represent real structures , not caustics Clark, Peek, and Miville-Deschenes et al 2019 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Peek and Clark 2019 Thin channels in HI represent cold structures seen in sodium 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps hNLS HI i/1019 ' 20 hNLS HI i/1019 ' 30 hNLS HI i/1019 ' 40 N=8306 hNLS HI i/1019 = 15.2 hNSS HI i/1019 = 0.0 N=14413 17.1 0.2 N=1825 19.3 1.3 N=376 20.2 2.3 N=109 20.6 3.4 N=2145 27.7 0.0 N=8856 28.7 0.4 N=3395 30.0 1.4 N=1306 30.6 2.4 N=443 31.2 3.3 N=386 39.8 0.0 N=2551 40.7 0.5 N=1709 41.4 1.4 N=839 42.1 2.4 N=432 42.3 3.4 Peek and Clark 2019 Thin Channels in HI represent cold structures seen in sodium 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Background galaxies can be used to trace dust at very high precision Peek & Graves 2010 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps We can even detect variation in Rv across the surface of the disk Schlafly, Peek et al. 2017 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Clark, Peek, Putman 2014 Linear features in HI trace the magnetic field, and can be used for the CMB 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Clark, Collins, Peek, Putman 2015 Linear features in HI trace the magnetic field, and can be used for the CMB 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Mapping the velocity field of the Milky Way allows us to trace formation Tchernyshyov & Peek 2017, Tchernyshyov, Peek, & Zasowski 2018 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps High Velocity Clouds are an indicator of the circumgalactic medium Putman, Peek, and Joung 2012 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps We can learn things about them by looking at absorption lines Peek+ 2016 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Si IV absorption from the ISM does not seem to be aware of the disk Zheng, Peek et al. 2019 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Z [kpc] −200 −100 0 100 200 0.0 0.5 1.0 −200 −100 0 100 200 0.0 0.5 1.0 −200 −100 0 100 200 0.0 0.5 1.0 vLSR [km s-1] vLSR [km s-1] Normalized Flux Quasar Star C IV 1548 C IV 1548 Quasar - Star CIV towards BHBs near quasars help us study the MW CGM Peek ,C26 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps But maybe they are at low latitude? FOGGIE 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps We found there’s lots of dust in the CGM, especially small galaxies Peek, Menard, & Corrales 2016 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps figure from John Wu We all want to image the CGM, but two points are better than one 

sub-Alfvénic sub-Alfvénic Fixed Fourier Power Fixed Fourier Power super-Alfvénic super-Alfvénic The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Deep Nets can help us find where the information lies in images Peek & Burkhart 2019 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Peek & Burkhart 2019 Deep Nets can help us find where the information lies in images 

The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps The Universe at Low Density The Circumgalactic Medium 21-cm Observations Morphology Velocity Fields Dust Standard Crayons Galactic Accretion Magnetized Fibers Kinetic Tomography The Dusty CGM Deep Learning High Velocity Clouds ISM Phases Next Generation Reddening Maps Deep Nets can help us find new images Peek et al 2017, Jones, Peek in prep 202X