Figure 1:  Binary disk merger simulations are useful in understanding merging disk galaxies observed in the sky. In general, they lack the realism and complexity of the cosmological assembly of old massive earl...

Figure 2:  Recent cosmological zoom simulations with strong stellar feedback of galaxies with spiral-like morphologies. The pictures show mock images of the stellar light. (a) SPH (GASOLINE) simulation of ) inc...

Figure 3:  The effect of stellar feedback on the star-formation histories of simulated disk galaxies. Stronger feedback results in the suppression of early star formation, relatively flat star-formation histori...

Figure 4:  Comparison of galaxy stellar mass functions from recent large-scale cosmological simulations of representative volumes of the Universe. The simulations include stellar and AGN feedback with the excep...

Figure 5:  Momentum generated in radiative supernova remnants for various ambient densities normalized by a fiducial initial momentum of km s−1 for an explosion energy of 1051 erg and two solar masses ejecta. ...

Figure 6:  (a–c) Snapshots of the vertical gas column–density distribution and (d–f) midplane temperatures for three simulations of stratified galactic disk ( pc−2) shaped by SNe exploding at a constant rate (d...

Figure 1:  (a) Top-down view of the Galaxy, with the Galactic Center at (0,0) and the Sun marked by an arrow. The grayscale shows an estimate for the distribution of free electrons (). Known magnetars are shown...

Figure 2:  (a) Several X-ray pulse profiles of magnetars in the 1–10-keV band. Courtesy of R.F. Archibald. (b) Examples of single bursts from soft gamma repeaters 1806−20 and 1900+14 shown with 7-ms time resolu...

Figure 3:  (a) Flux evolution during and after the outburst of 1E 2259+586. Note the initial rapid decrease in flux on the first day, when the vast majority of associated short bursts were detected, followed by...

Figure 4:  (a) The 2004 giant flare from SGR 1806−20. (Bottom) 20–100-keV time history with 0.5-s resolution from the RHESSI satellite, showing the initial spike (which saturated the detector) at 26 s. The inse...

Figure 5:  (a) Broadband phase-averaged X-ray spectrum from combined Swift/XRT (green) and NuSTAR observations of 1E 2259+586. Adapted from ) with permission. The best-fit model of an absorbed blackbody plus tw...

Figure 6:  Phase-resolved spectroscopy of SGR 0418+5729. The spectral flux is shown in the energy versus phase plane for XMM-Newton/EPIC data. The image was obtained by binning the EPIC source counts into 100 p...

Figure 7:  Formation of the current sheet in an over-twisted magnetosphere. Reconnection begins at trec (panel d). Color shows toroidal current density; lines are the poloidal magnetic field lines. One field li...

Figure 8:  (a) A magnetic loop in the j-bundle. Relativistic particles are assumed to be injected near the star (black sphere), and a large e± multiplicity develops in the adiabatic zone B>1013 G (blue shading...

Figure 1:  Mass-radius curves of planets with radii below 4 Earth radii and masses below 30 Earth masses. Planets are color-coded by the stellar flux they receive (compared with Earth). Hypothetical temperature...

Figure 2:  Estimate of Earth's annual and global mean energy balance, and sketch of the modern carbonate-silicate cycle. Data from Trenbeth et al. () and .

Figure 3:  The oxygen cycle on Earth.

Figure 4:  Boundaries of the HZ for our Sun throughout its evolution: (a) post- MS, (b) MS, and (c) pre-MS. The orbital distances corresponding to the boundaries of the HZ evolve due to the star's changing lumi...

Figure 5:  Detected exoplanets orbiting in the empirical habitable zone of their host stars (solid red and blue lines), as well as a three-dimensional model inner habitable zone limit (dashed line). (a) Transit...

Figure 6:  Schematics of relative orbital light curves for planets and planets with unresolved moons in a circular orbit with and without an atmosphere in (a) reflected light and (b) thermal emission, assuming ...

Figure 7:  Absolute flux comparison of Jupiter, Venus, Earth, and Mars in our Solar System as well as a hot extrasolar giant planet shown here as blackbodies for the (a) Sun and (b) M0 host star at a distance o...

Figure 8:  Spectra of Earth, Venus, and Mars at a resolution (λ/Δλ) of approximately 100 in the (a) visible to near-infrared bands (the reflected flux of Mars has been multiplied by 10 to appear) and (b) therma...

Figure 9:  (a) Visible, (b) near-infrared reflectivity, and (c) infrared emission spectra of Earth (model shown in red). Data (black) are from earthshine measurements and space measurements, respectively.

Figure 10:  (a) Ultraviolet, (b) visible, (c) near-infrared, and (d) infrared transmission spectra of a transiting Earth analog orbiting the Sun (black line). In the visible to infrared spectrum (b,c), refractio...

Figure 11:  Changes in Earth's atmospheric composition through geological times influence its spectrum: (a) visible to NIR, and (b) IR spectral features on an Earth-like planet show considerable changes. Emergen...

Figure 12:  Stellar and model surface UV flux for (a) Sun–Earth for three geological epochs show how the UV environment changed throughout Earth's history from a prebiotic Earth (3.9 Ga) to a low-oxygen environm...

Figure 13:  (a) Effective heights: Earth (black) compared with a super-Earth with three times Earth's gravity (green) around the Sun. (b) Comparison of atmospheric transmission of an Earth-analog planet around t...

Figure 14:  Atmospheric features in the (a) visible and (b) infrared for Earth-like planets orbiting different host stars.

Figure 1:  Citation history for the ) paper for three different subject areas.

Figure 2:  Percentage of articles in ArXiv astro-ph abstracts containing the terms (a) Bayesian and (b) MCMC. Computed using the code arxiv.py; courtesy of Dustin Lang.

Figure 3:  Fitting a straight line to data with outliers. The outliers are shown as red points. The dashed line is the best-fit line when an outlier model is not used. The solid line is the best-fit line with a...

Figure 4:  Prior for the slope of a straight line. (a) A prior uniform in slope a, and straight lines with constant interval Δa. (b) A prior uniform in angle θ=tan−1(a) that is symmetric with respect to rotatio...

Figure 5:  MCMC chains for different widths of the proposal distribution. The variable x is sampled from a Gaussian distribution N(0.0, 1.0) using MCMC with different proposal distributions. The proposal distri...

Figure 6:  Analysis of group mean using a hierarchical Bayesian model. The dashed line is the global mean from all data points. The blue dots are group means computed from the data points in the group. The gree...

Figure 7:  Comparison of two methods to handle nuisance parameters. Here the nuisance parameter is the true coordinate that is related to the observed coordinate via a given uncertainty. In the DA algorithm, th...

Figure 8:  (a) Radial velocity as a function of time for a star in a binary system. The parameters of the binary system are listed on the top. The green line is the best-fit solution obtained using an MCMC simu...

Figure 9:  The APOGEE spectra of four stars (gray line) along with the best model spectra generated by The Cannon algorithm (cyan line) along with scatter around the fit. Each row shows the spectra of a single ...

Figure 10:  (a) The power density of four stars observed with Kepler showing solar-like oscillations along with a best-fit model (solid black). The hump is the approximate Gaussian-like envelope that modulates t...

Figure 11:  A 3D map of interstellar dust reddening in the Milky Way based on Pan-STARRS 1 and 2MASS photometry. Shown are the mean differential reddening in different heliocentric distance ranges. The map is ad...

Figure 12:  (a) Radial velocity dispersion as a function of radius for halo stars in the Milky Way. (b) Posterior distribution of virial mass and the concentration parameter of the Milky Way's dark matter halo. ...

Figure 1:  The all-sky map of polarized thermal dust emission observed at 353 GHz by Planck showing the orientation of B⊥ as the flow pattern. The colors represent polarized intensity, with the maximum intensit...

Figure 2:  All-sky maps of (a) synchrotron emission and (b) the polarization emission at 1,400 MHz, and of the synchrotron emission (c) at 23 GHz with E-vectors observed by WMAP and (d) at 30 GHz observed by Pl...

Figure 3:  (a) The rotation measure excess toward the Hii region Sh 2-27. Adapted from ) by permission of the AAS. (b) The zero-level restored polarization map (in color) of the Hii region W1 at λ6 cm showing d...

Figure 4:  Magnetic field orientations in the (a) Pipe and (b) Musca molecular clouds inferred from the polarized thermal dust emission by Planck images (same color scheme as ) and starlight polarization (black...

Figure 5:  Composite spatial magnetic-energy spectrum in the Galaxy. The top-left thick line was obtained by ) for magnetic fields in the Galactic disk. The thin solid and dashed/dotted lines at k≳10 indicate t...

Figure 6:  After filtering out anomalous RMs, the RM distribution of extragalactic radio sources in panel a shows a striking antisymmetric feature in the inner Galactic quadrants (i.e., |l|<90°) with respect to...

Figure 7:  (a) RM amplitudes of pulsars in the mid-latitude regions of the inner Galaxy are compared with the averaged RM sky (i.e., GRM, plotted around 30 kpc with a shift of the scaled values of Galactic long...

Figure 8:  RM distribution of pulsars and background radio sources of |b|<8° in Galactic coordinates. The central part shows pulsars projected onto the Galactic disk with distances derived by using the electron...

Figure 9:  (a) A schematic map of radio filaments and threads near the Galactic Center observed at λ20 cm indicates the poloidal magnetic fields mostly running perpendicular to the Galactic plane. Adapted from ...

Figure 10:  Orientations of organized magnetic fields in galactic disks always follow spiral arms, as seen in (a) NGC 2997 with B-vectors (i.e., E-vectors rotated by 90°) from the polarization map observed with ...

Figure 11:  Orientations of organized magnetic fields in (a) a bar galaxy, (b) a dwarf irregular galaxy, and (c) a ring galaxy. The resolution is given by the HPBW, as marked in a corner of every plot. (a) NGC 1...

Figure 12:  As a tracer of magnetic fields, diffuse sources of radio synchrotron emission observed from galaxy clusters are shown as (a) radio halos, e.g., A2163, with the radio total intensity contours overlaid...

Figure 13:  Intracluster magnetic fields are revealed by (a) the RM excess of radio sources behind galaxy clusters with data from ) and ), (b) observed RM patches (e.g., a source inside A2142), and (c) the dispe...

Figure 14:  Real dispersion of RRM distributions (WRRM0, after taking out the contribution of RRM uncertainties σRRM) is shown as a function of redshift for RMs from literature (filled red circles) and from the ...

Figure 1:  A diagram of the CGM. The galaxy's red central bulge and blue gaseous disk are fed by filamentary accretion from the IGM (blue). Outflows emerge from the disk in pink and orange, whereas gas that was...

Figure 2:  Four important problems in galaxy evolution viewed with respect to M⋆. (a) The gas depletion timescale for star-forming galaxies at z∼0, with Mgas from ) and from ); the shading denotes ±0.15 dex s...

Figure 3:  These simulated views (from EAGLE; adapted from and ) of the CGM are more sophisticated but possibly just as uncertain as . The three columns render a single galaxy with M⋆=2.5×1010 M⊙ at z=0 in den...

Figure 4:  A range of ion equivalent–width (rest-frame) measurements for a compilation of published surveys; refer to Supplemental Figure 3 for alternate versions showing column densities, where available. We p...

Figure 5:  A selection of absorption-line data and Voigt profile fits from the COS-Halos survey (), showing a range of metal ions and Hi on a common velocity scale with the galaxy at v=0 km s−1 on the x-axis.

Figure 6:  Metal absorption lines (ions) of the CGM from neutral to Oviii having 19 <λrest<6000 Å shown on a phase (T-nH) diagram within Rvir of the z=0 EAGLE simulation shown in . The points are colored accord...

Figure 7:  A synthesis of CGM mass density results for cold gas (pink, ), cool gas (purple, ), warm gas traced by Ovi (green; , ), X-ray-emitting gas (yellow, NGC1961; ), and dust (brown, ). An NFW profile scal...

Figure 8:  (a) An accounting of CGM baryon budgets for all physical phases. The solid bars show the minimum values, whereas the hatched regions show the maximal values. The other three panels show simulated bar...

Figure 9:  (a) A metals census of the CGM around star-forming z∼0 galaxies following ), including a sub-L* budget from ). As in , stars are red, ISM gas is blue, ISM dust is orange, the cool CGM is purple, the ...

Figure 10:  Two views of CGM metallicity. (a) Two LLS distributions from ) and ). This comparison clearly shows evolution in the LLS metallicities over time. (b) Trends in Mgii and Civ line densities per unit re...

Figure 11:  Three views of the CGM and quenching. (a) A trend in Lyα equivalent width over three decades in stellar mass from COS-Halos () and COS-Dwarfs (). As shown by ), the presence of Hi around red, passive...

Figure 1:  Leon Mestel and Ken Freeman, Canberra.

Figure 2:  Olin Eggen, Donald Lynden-Bell, and Allan Sandage, Cambridge 1986. Photo credit: Prof. Gerry Gilmore.

Figure 3:  Gérard and Antoinette de Vaucouleurs, Paris 1962.

Figure 1:  Point-source X-ray luminosity functions for star-forming (blue) and elliptical (red) galaxies with data for star-forming galaxies from ) and ). Abbreviation: SFR, star-formation rate.

Figure 2:  A comparison of different ultraluminous X-ray source and Galactic black hole X-ray binary spectra. Ultraluminous (UL) spectra are distinctly two-component, with a soft excess and a hard component tha...

Figure 3:  High-frequency QPO frequency (second harmonic) versus black hole mass. The systems in order of increasing mass are for GRO J1655−40, XTE J1550−564, and GRS 1915+105. The dashed line is a linear regre...

Figure 4:  X-ray to optical flux ratio of ULXs with unique point-like counterparts found in Hubble Space Telescope images from ). The ULX flux ratios are similar to those of active LMXBs suggesting that the opt...

Figure 5:  Hubble Space Telescope image of Heii λ4686-line emission surrounding Holmberg II X-1 from ). The ultraluminous X-ray source position is marked with a green cross. The arrow points north and has a len...

Figure 6:  Emission line widths of Heii and Hα in the spectra of ultraluminous X-ray source optical counterparts. From left to right, the points are for Holmberg II X-1, NGC 4559 X-7, NGC 5408 X-1, Holmberg IX ...

Figure 7:  A diagram of a supercritical accretion flow. The accretion disk (red) becomes geometrically thick at Rsph, and within this radius a massive, optically thick outflow is blown from the top of the disk ...

Figure 8:  Bolometric disk luminosity versus the disk inner temperature for the BHB, LMC X-3 (data from ), and the two intermediate-mass black hole candidates, M82 X-1 (data from ) and ESO 243-49 HLX-1 (data fr...

Figure 1:  A not-to-scale diagram of the environment of the Galactic MBH in the center of the Milky Way (). Stars are denoted by the small circles, color-coded by spectral type; binaries are denoted by two star...

Figure 2:  The effects of strong mass segregation on the density distribution of a simplified population with MS stars and remnants (WDs, , and stellar BHs) around a Milky Way–like nucleus with (). (a) The num...

Figure 3:  The relaxation timescales in the Milky Way's nucleus near the 4×106- MBH, shown against the typical ages of various stellar populations there, assuming a relaxed stellar cusp (). The NR time TNR (blu...

Figure 4:  (a) A schematic of loss-cone dynamics in (a, j) phase space. At the scattering rates in loga=−logE and are comparable, but once , the scattering along is much faster (Section 3.1.1). Close to the ...

Figure 5:  Snapshots of stellar tracks from a Monte Carlo integration of the equation describing orbital evolution around an MBH under the combined effects of NR, RR, and GW emission (). The snapshots (differe...

Figure 6:  Plunge and EMRI rates per galaxy in steady state, as a function of , assuming a simplified single mass population composed of 10- stars (stellar BHs), scaled to the Galactic Center by the relation w...