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For most of my educational and professional life, I pursued a fairly standard trajectory. A bachelor's degree in physics and astronomy, a master's in optical physics, and a Ph.D. in astronomy prepared me for a postdoctoral fellowship and subsequent work as a scientist at NASA's Goddard Space Flight

Over the past 15 years, professional astronomers, their societies, and associated funding agencies have collaborated to improve astronomy teaching and learning at the introductory undergraduate lev...

M94 (NGC 4736) is investigated using images from the Ultraviolet Imaging Telescope (FUV-band), Hubble Space Telescope (NUV-band), Kitt Peak 0.9-m telescope (H-alpha, R, and I bands), and Palomar 5-m telescope (B-band), along with spectra from the International Ultraviolet Explorer and Lick 1-m telescopes. The wide-field UIT image shows FUV emission from (a) an elongated nucleus, (b) a diffuse inner disk, where H-alpha is observed in absorption, (c) a bright inner ring of H II regions at the perimeter of the inner disk (R = 48 arcsec. = 1.1 kpc), and (d) two 500-pc size knots of hot stars exterior to the ring on diametrically opposite sides of the nucleus (R= 130 arcsec. = 2.9 kpc). The HST/FOC image resolves the NUV emission from the nuclear region into a bright core and a faint 20 arcsec. long ``mini-bar'' at a position angle of 30 deg. Optical and IUE spectroscopy of the nucleus and diffuse inner disk indicates an approximately 10^7 or 10^8 yr-old stellar population from low-level starbirth activity blended with some LINER activity. Analysis of the H-alpha, FUV, NUV, B, R, and I-band emission along with other observed tracers of stars and gas in M94 indicates that most of the star formation is being orchestrated via ring-bar dynamics involving the nuclear mini-bar, inner ring, oval disk, and outer ring. The inner starburst ring and bi-symmetric knots at intermediate radius, in particular, argue for bar-mediated resonances as the primary drivers of evolution in M94 at the present epoch. Similar processes may be governing the evolution of the ``core-dominated'' galaxies that have been observed at high redshift. The gravitationally-lensed ``Pretzel Galaxy'' (0024+1654) at a redshift of approximately 1.5 provides an important precedent in this regard., revised figure 1 (corrected coordinate labels on declination axis); 19 pages of text + 19 figures (jpg files); accepted for publication in AJ

We present the first far-ultraviolet (FUV; λ ~ 1500 A) image of the nearby peculiar SAB(r)bc galaxy NGC 3310. The small 15'' (945 pc) diameter circumnuclear starburst ring is the most luminous structure, producing 30% of the total observed FUV luminosity. Diffuse emission from the inner disk (20'' < R < 40'') contributes another ~20% of the observed FUV flux. A linear feature (the "arrow") appears to be a star-forming tidal feature. A diffuse arc observed at optical wavelengths (the "bow") is not visible in the FUV and is probably a tidally induced shell composed of older stars. Mean star formation rates range from 0.031 M☉ yr-1 kpc-2 in the arrow to 2.1 M☉ yr-1 kpc-2 at the brightest FUV source. The striking similarity between the R1/4 law behavior of the FUV and B-band surface brightness profiles, combined with the very blue colors of NGC 3310, strongly argues that the present morphology is the result of a global starburst triggered by a merger with a dwarf companion.

We have undertaken an imaging survey of 34 nearby galaxies in far-ultraviolet (FUV, ~1500A) and optical (UBVRI) passbands to characterize galaxy morphology as a function of wavelength. This sample, which includes a range of classical Hubble types from elliptical to irregular with emphasis on spirals at low inclination angle, provides a valuable database for comparison with images of high-z galaxies whose FUV light is redshifted into the optical and near- infrared bands. Ultraviolet data are from the UIT Astro-2 mission. We present images and surface brightness profiles for each galaxy, and we discuss the wavelength-dependence of morphology for different Hubble types in the context of understanding high-z objects. In general, the dominance of young stars in the FUV produces the patchy appearance of a morphological type later than that inferred from optical images. Prominent rings and circumnuclear star formation regions are clearly evident in FUV images of spirals, while bulges, bars, and old, red stellar disks are faint to invisible at these short wavelengths. However, the magnitude of the change in apparent morphology ranges from dramatic in early--type spirals with prominent optical bulges to slight in late-type spirals and irregulars, in which young stars dominate both the UV and optical emission. Starburst galaxies with centrally concentrated, symmetric bursts display an apparent ``E/S0'' structure in the FUV, while starbursts associated with rings or mergers produce a peculiar morphology. We briefly discuss the inadequacy of the optically-defined Hubble sequence to describe FUV galaxy images and estimate morphological k-corrections, and we suggest some directions for future research with this dataset., Accepted for publication in the ApJS. 15 pages, 17 JPEG figures, 10 GIF figures. Paper and full resolution figures available at http://nedwww.ipac.caltech.edu/level5/Kuchinski/frames.html

Far ultraviolet FUV imagery of the edge-on, Sc/SBd galaxy, NGC 4631 reveals very strong FUV emission, resulting from active star formation, uniformly distributed along the galactic mid- plane. Multi-band imagery, HI and HII position-velocity curves and extinction considerations all imply that the emission is from the outer edges of the visible galaxy. The overall FUV morphology of this edge-on disk system is remarkably similar to those of the so-called "chain galaxies" evident at high redshift, thus suggesting a similar interpretation for at least some of those distant objects. FUV, U, B and V magnitudes, measured for 48 star forming regions, along with corresponding H-alpha and H-beta measurements are used to construct diagnostic color-color diagrams. Although there are significant exceptions, most of the star forming regions are less massive and older than 30 Doradus. Comparison with the expectations from two star formation models yields ages of 2.7 to 10 Myr for the instantaneous burst (IB) model and star formation cut-off ages of 0 to 9 Myr for the continuous star formation (CSF) model. Interpreted in terms of the IB model the photometry implies a total created mass in the 48 star forming regions of 25 million solar-masses. When viewed as resulting from constant star formation the photometry implies a star formation rate of 0.33 solar-masses/yr. These results are compared to those derived from FIR and radio observations. Corrections for FUV emission reprocessed by interstellar grains are estimated., Comment: 29 pages including 6 encapsulated Postscript figures; accepted for publication in ApJ; changed table format

What is the general morphology of the diffuse interstellar medium? Is it mostly uniform or clumpy? Are the clumps mostly in the form of spheroidal clouds, sinuous filaments, extended sheets, or discrete shells? And do the clumps or the voids better define the overall structure? By addressing these morphological questions, one can better constrain the dynamical processes that are most responsible for shaping; and energizing the ISM.

When viewed from above the Earth’s atmosphere, the nighttime ultraviolet sky background is profoundly dark. Recent measurements indicate that the diffuse UV sky background is up to 100 times (5 magnitudes) fainter than the equivalent visible background as measured from the ground. Much of this difference can be attributed to the Sun’s lower emissivity at UV wavelengths, leading to reduced irradiation of and scattering by the interplanetary dust. Because the resulting Zodiacal light is so much weaker in the UV, a comprehensive characterization of the UV sky can yield important information on the more distant Galactic and extragalactic backgrounds and, ultimately, on their material origins (see Brosch, this volume, p. 57).

The Ultraviolet Imaging Telescope (UIT) has returned the first significant sample of ultraviolet imagery of galaxies combining a large field-of-view and spatial resolution comparable to ground-based observatories. During the Astro Spacelab missions, UIT obtained spatially-resolved far-UV (λλ 1500 A) imagery of ∼35 disk galaxies. We have utilized the FUV light profiles and morphology to characterize the high-mass stellar populations in these systems. A variety of radial light profiles are found, including two systems, NGC 4214 and NGC 3310, which exhibit R1/4 profiles produced by their Population I stellar components.

These Proceedings culminate an exciting year of brainstorming, collaborating, and communicating. Our primary aim for the “UV Universe” conference was to bring together researchers of the local and remote universe with the hope that the two cultures would gain new insights on the evolution of galaxies and the intergalactic medium (IGM) through cosmic time. The UV theme came from the fact that recent deep views of extremely distant galaxies are revealing restframe UV emission that has been redshifted into the visible spectrum. By comparing the UV properties of local galaxies and the IGM with the restframe UV properties of their high-redshift counterparts, we hoped to address whether or not there is compelling evidence for significant evolution of galaxies over the last 10–15 billion years. Fortunately, the conference itself evolved over a much shorter timescale. The following are some recollections along the way.

The Ultraviolet Imaging Telescope (UIT) was flown as part of the Astro observatory on the Space Shuttle Columbia in December 1990 and again on the Space Shuttle Endeavor in March 1995. Ultraviolet (1200-3300 Angstroms) images of a variety of astronomical objects, with a 40 arcmin field of view and a resolution of about 3 arcsec, were recorded on photographic film. The data recorded during the first flight are available to the astronomical community through the National Space Science Data Center (NSSDC); the data recorded during the second flight will soon be available as well. This paper discusses in detail the design, operation, data reduction, and calibration of UIT, providing the user of the data with information for understanding and using the data. It also provides guidelines for analyzing other astronomical imagery made with image intensifiers and photographic film., Comment: 44 pages, LaTeX, AAS preprint style and EPSF macros, accepted by PASP

Recent rest-frame ultraviolet imaging of galaxies at apparently high redshift have revealed a population of very blue galaxies with aspect ratios approaching 30 which have been interpreted to be chains of star formation regions in the initial stages of galaxy formation [1]. We compare these optical observations with rest-frame far-ultraviolet observations of nearby edge-on galaxies with a view to illustrating their noteworthy similarities. For the comparison we use far ultraviolet (FUV) images of NGC 253 (SAB(s)c), NGC 891 (SA (s)b), NGC 3034 (M82)(I0), NGC 4248 (I0), UGC 6697 (Im), and NGC 4631 (SB(s)d) which were recorded by the Ultraviolet Imaging Telescope. We focus primarily on NGC 4631, 7.5 Mpc distant, which in the FUV exhibits a linear beaded structure, an axial ratio of ∼24 and a (λλ 1520 A)-U color of −0.70. At z≈1.9 (λλ 1520 A)-U would approximate (B–I) and would appear to be very blue. NGC 4248 and UGC 6697 are additional examples of edge-on galaxies which give the appearance of “chain galaxie...

During the Astro-1 Spacelab missions, the Ultraviolet Imaging Telescope (UIT) obtained spatially-resolved far (λ∼1500 A) and mid-UV (λ∼2500 A) imagery of ∼25 nearby galaxies. The sample spans the Hubble sequence including ellipticals, disk systems and irregular galaxies. These images have a resolution of ∼3 ′′ , a limiting surface brightness, μ 1500 ≈25 mags arcsec −2 , and cover the full angular extent of each system, many of which have angular diameters exceeding 5 ′ . The UIT data permit determination of both global FUV properties with improved photometric precision, and detailed investigation of galaxian morphology at intermediate (spiral arms, nuclear rings), and small (star-forming complexes) scales. We are constructing datasets which combine the UV imagery obtained by UIT with associated optical (UBVRI,Hα) and near-IR (JHK) images of comparable depth and spatial resolution obtained at ground-based telescopes. Our primary goal is to provide a morphological Atlas of Galaxies extending from the far-ultraviolet (λ∼1500 A) to near-infrared (λ∼2.2μ) wavelengths. The Astro-1/UIT Atlas contains registered and flux-calibrated images at FUV, NUV, R and Hα bandpasses for galaxies which are spatially resolved, surface brightness profiles, and integrated magnitudes (or upper limits) for the entire sample.

Deep high-resolution imaging of galaxies at high-redshift has revealed a remarkable diversity of emission structures in the restframe ultraviolet. To better understand these remote and primeval realms, it is important to compare them with UV-emitting counterparts in the local universe. As part of two Spacelab/Astro missions, the Ultraviolet Imaging Telescope (UIT) has obtained wide-field (40-arcmin), well-resolved (3 arcsec) images of ∼50 nearby galaxies in the vacuum ultraviolet. Followup groundbased imaging at UBVRI and Hα bands has been completed for most of the well-resolved galaxies. Analysis of a small subset of these galaxies has revealed strong variations in the emission morphologies as a function of restframe wavelength. In the present study, we compare the UV morphologies of barred and unbarred spiral galaxies as a function of Hubble type and absolute luminosity. Radial extents are measured relative to their visible counterparts, and characteristic UV emission structures are identified (e.g. rin...

We present new evidence for tidal interactions having occurred in the disk of M101 in the last 10^8 - 10^9 years. Recent imaging of the far-ultraviolet emission from M101 by the Shuttle-borne Ultraviolet Imaging Telescope (UIT) reveals with unprecedented clarity a disk-wide pattern of multiple linear arm segments (``crooked arms''). The deep FUV image also shows a faint outer spiral arm with a (``curly tail'') feature that appears to loop around the supergiant HII region NGC 5471 - linking this outlying starburst with the rest of the galaxy. These FUV-bright features most likely trace hot O & B-type stars along with scattered light from associated nebular dust. Counterparts of the outermost ``crooked arms'' are evident in maps at visible wavelengths and in the 21-cm line of HI. The inner-disk FUV arms are most closely associated with H$��$ knots and the outer (downstream) sides of CO arms. Comparisons of the ``crooked arm'' and ``curly tail'' morphologies with dynamical simulations yield the greatest similitude, when the non- axisymmetric forcing comes from a combination of ``external interactions'' with one or more companion galaxies and ``internal perturbations'' from massive objects orbiting within the disk. We speculate that NGC 5471 represents one of these ``massive disturbers'' within the disk, whose formation followed from a tidal interaction between M101 and a smaller galaxy., Paper format (latex); length of paper (8); 4 gif figure files; uses aas2pp4.sty AASTeX macro file; to be published in Part I of the Astrophysical Journal

Mosaics at 60 μm and 100 μm have been constructed of the 60°×60° area covering the Galactic center, bulge, molecular ring, and nearby clouds of emitting dust. We examine the relationship between various tracers of the interstellar medium and the fine‐scale structure that is evident in these mosaics. We pay special attention to the nearby Ophiucus cloud complex, a spectacular showcase for interactions between hot stars and dense interstellar matter. Here, the CO emission correlates well with much of the warm dust emission, whereas the Hα and FIR emission appear mostly uncorrelated. The warmest FIR colors are associated with the positions of young hot stars. Closer to the Galactic plane, the FIR fine structure is more likely tracing enhancements of warm dust in the more distant molecular ring and central bulge.

Much of this meeting has been concerned with the teaching of introductory astronomy to children, teenagers, and young adults. Introductory astronomy for working and retired adults has been given short shrift, however. Because the mature population is significant in number and in its influence on governmental support for astronomy, I thought that some mention should be made. My own experience concerns the educational programs that are available to mature students in the United States.Most working adults are restricted by their jobs to taking classes in the evening. Most large universities in the United States provide such classes. These are often administered by organizations that are completely autonomous from the “host” school. A typical arrangement is for the school to provide classroom space, access to audio-visual equipment (sometimes), and university credit for those who register for credit. The “adult education,” “continuing education,” or “university extension” organization handles the rest. It obtains the necessary faculty to teach the courses, advertises the classes, and administers the registration and grading. For the “credit” courses in astronomy, the most common teachers are graduate students and postdoctoral fellows looking for some extra cash and teaching experience. There is no real impetus for regular faculty members to teach these classes. This is an unfortunate circumstance that could be remedied by some private, state, or federal funding of endowed “chairs” in adult education.

Red H-alpha and R-band CCD images of the M82 galaxy were obtained and compared with corresponding NIR S III forbidden-line and I-band images and with a smaller Br-gamma infrared-array image of the central 500 pc. Results furnish evidence of circumnuclear pileup in M82, probably toroidal in form, which is dynamically linked to the central (bilobal) starburst and which is now collimating the subsequent eruptions and emergent radiation.

Estimates are presented of the distances to the nearest CO-emitting material along 31,500 lines of sight in the northern Milky Way on the basis of an analysis of the Massachusetts-Stony Brook survey of CO emission in the first Galactic quadrant. For Galactic latitudes between -1.0 and +1.0 deg and longitudes between 8 and 53 deg, significant CO emission (greater than 1.2 K) and associated optical obscuration (greater than 1.2 mag) is found within 2 kpc of the sun in 21,149 of the lines of sight. Much of this local emission is associated with the Aquila Rift system of dark clouds. Another 8,179 lines of sight are obscured at distances between 2 and 10 kpc. The remaining 2,172 lines of sight are completely free of significant CO emission. These cloud-free positions can be used as 'offs' for radio or IR spectroscopy of molecular sources in the Galactic plane, as 'ons' for studies of the diffuse intercloud medium itself, and as possible 'windows', through which distant disk and bulge stars might be optically observable.

Results of a deep near-infrared imaging survey of low-luminosity cold IRAS sources in the Taurus dark cloud are discussed. The images involved identify the compact sources energizing the IRAS sources, identify infrared nebulosity around numbers of the invisible sources, and reveal the large-scale (about 1000 to 10,000 AU) morphology of this nebulosity. Some of the invisible sources show a clear bipolar or monopolar morphology suggesting a close relation of the nebulosity with a bipolar mass outflow. It is concluded that the nebulosity is likely due to scattering of radiation from the central source by the dust associated with the mass outflow extending to the poles of a circumstellar dust disk.

H-alpha, R, and I band CCD images of the posteruptive irregular galaxy NGC 1569 are presented. The discovery of two archlike structures of diffuse H-alpha emission located more than 1 kpc beyond the star-forming bar is reported. These features are used to estimate an age for the near-nuclear starburst that created them along with other filamentary and armlike structures previously seen in H-alpha photographs. The gravitational and kinematic energies associated with the H-alpha arcs are estimated to be orders of magnitude higher than can be provided by a single supernova explosion. Coherent outbursts involving thousands of supernovae each could explain the diffuse H-alpha features without exceeding the starbirth rate inferred from the total H-alpha luminosity of the galaxy. 46 refs.

H-alpha (6563 A) and near-infrared forbidden S III line (9532 A) data are presented for the Sc galaxy NGC 253. Anomalous enhancements in the forbidden S III/H-alpha emission ratio throughout the inner disk may indicate the presence of concealed H II regions. Visual extinctions range from 3-7 mag. The results suggest that within the inner 7 kpc of the disk roughly 95 percent of the ionized gas is obscured from view at H-alpha, and that on large scales the massive star formation depends linearly on the available molecular gas. NGC 253 differs from other Sc-type galaxies by the stronger concentration of star-forming activity toward the nucleus, the richer presence of massive star formation, and the higher overall star-forming efficiency. 50 references.