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January 1997

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Volume 14, Number 1

SPACE TE LESCOPE SCIENCE INSTITUTE
Highlights of this issue:

Newsletter
Astronomy with HST

· AURA science and functional awards to Leitherer and Hanisch -- pages 1 and 23 · Cycle 7 to be extended
-- page 5

· Cycle 7 approved program listing -- pages 7-13

Climbing the Starburst Distance Ladder
C. Leitherer
Massive stars are an important and sometimes dominant energy source for a galaxy. Their high luminosity, both in light and mechanical energy, makes them detectable up to cosmological distances. Stars ~100 times more massive than the Sun are one million times more luminous. Except for stars of transient brightness, like novae and supernovae, hot, massive stars are the most luminous stellar objects in the universe. Massive stars are, however, extremely rare: The number of stars formed per unit mass interval is roughly proportional to the -2.35 power of mass. We expect to find very few massive stars compared to, say, solar-type stars. This is consistent with observations in our solar neighborhood: the closest really massive star is the O4 supergiant (~50 solar mass) Puppis at a distance of about 500 pc; large volumes need to be sampled to observe significant numbers of massive stars. Our Galaxy does not qualify as a starburst, which is a term denoting powerful star formation events in galaxies. Even the most luminous starforming regions in our Galaxy are tiny on a cosmic scale. They are not dominated by the properties of an entire population but by individual stars. Therefore stochastic effects prevail. Extinction represents a severe problem when a reliable census of the Galactic high-mass star-formation history is atempted, especially since massive stars belong to the extreme Population I, with correspondingly small vertical scale heights. Moreover, the proximity of Galactic regions -- although advantageous for detailed studies of individual stars -- makes it difficult to obtain integrated properties, such as total emission-line fluxes of the ionized gas. Nevertheless, observations in the Galaxy allow us to study individual massive stars in great detail -- an important consideration before venturing out to distant populations. The Carina region (= NGC 3372) hosts one of the more spectacular highmass star formation regions in the Galaxy. Its proximity of about 2 kpc permits detailed studies of the stellar content. Several O3 stars have been found in Trumpler 14/16. They are the earliest and most massive species in the MK classification scheme. HD 93128, HD 93129A, HD 93205, and HDE 303308 have masses around 100 solar masses. The enigmatic object Carinae is located in this region as

Figure 1. Composite B, V, I WFPC2 (PC) image of NGC 1741 obtained by P. Conti, in collaboration with the author and W. Vacca. Field size is 35 arcsec. North is up and east to the left. well. Car is a luminous blue variable (LBV), a short evolutionary phase when a substantial fraction of stellar mass is shed and ejected into the ISM.

Editor's Note: Each year AURA makes two awards to the staff of STScI, one for scientific achievement, and one for functional performance. This year's science award went to Dr. Claus Leitherer, who provided the accompanying article on his work. The functional award was to Dr. Robert Hanisch, and his article appears later in this Newsletter.

30 Doradus: the Rosetta Stone
High-mass star-formation regions in the Local Group of galaxies are excellent laboratories to study starbursts: their proximity (with respect to galaxies in the Hubble flow) permits detailed studies of individual
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ST ScI Newsletter

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Director's Perspective

Director's Perspective

T

he Cycle 7 TAC has now met and given its recommendations on the programs it reviewed that should be carried out on HST after the new instruments are installed. Notification letters to the PIs of all submitted proposals giving the TAC/panels recommendations should be received by early January. Not surprisingly, a number of Cycle 7 programs will make use of the long-slit and UV capabilities of STIS and the IR

capabilities of NICMOS to make observations that were not possible before, and which are certain to produce interesting research in a number of areas. The TAC, chaired this cycle by Dr. Mike Shull of the Univ. of Colorado, considered a number of large programs for implementation given that all of the previous Key Projects will soon have been completed, and it recommended time for one of them. To be carried out under the supervision of G. Gilmore of IOA, Cambridge, this program will obtain images of clusters in the Large Magellanic Cloud to construct color-magnitude diagrams of the systems. According to the new policy governing large programs recommended by the Institute Advisory Committee, the TACs of all succeeding cycles may recommend the allocation of time for up to as many as three large programs (>100 orbits) each cycle. Launch of the second HST servicing mission, STS-82, is soon upon us. Preparations have been proceeding nominally, and both instruments are ready for installation in the telescope. Concerted efforts have already been underway for some time among the HST Project, the Institute, and the NICMOS and STIS instrument teams to prepare for bringing the new instruments on- line and commencing with their in-flight calibration. As was done after the first servicing mission an Early Release Observations program will be carried out, coordinated by Dr. A. Saha, which should give early demonstration of the capabilities of the new instruments. Thus some scientific results from the refurbished HST should be forthcoming a few months after the mission. Institute staff are working with Goddard scientists and others to plan the next phase of studies for the Next Generation Space Telescope, the follow-up mission to HST recommended by AURA's "HST and Beyond" Committee. We have also decided to sponsor, jointly with GSFC, a conference devoted to the scientific program for a mission having the characteristics defined in the mission studies recently completed. Initial plans are to hold the meeting at Goddard in early April 1997; details will be available by the time of the Toronto AAS meeting in January. We hope for broad community participation to build appreciation for the promise of this mission.

Bob Williams, Mike Hauser

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January 199 7

Starburst Distance

from page 1

stars, yet their distance (with respect to Milky Way clusters) makes it possible to obtain integrated properties as well. Although more luminous than Galactic regions, they are still underluminous in comparison with the starburst prototypes below. Numerous studies of the Rosetta Stone 30 Dor (with its ionizing cluster NGC 2070, whose massive center is R136) exist. Crowding becomes severe for stellar spectroscopy in the central R136 region. HST allows spatially resolved aperture spectroscopy of individual stars. Ultraviolet spectra of several hot, luminous stars suggest temperatures above 40 000 K, luminosities around 106 LSun, and masses above 50 MSun. The wind properties are particularly outstanding. Strong P Cygni profiles of C IV, N V, and He II indicate high mass loss at rates of 10-5 MSun per year and above. These wind lines are strong enough to be detectable in even the most distant starburst galaxies, as will be discussed below. The interstellar environment in 30 Dor differs from that of smaller Galactic H II regions. Galactic regions, such as Trumpler 14/16 are not massive enough to form significant numbers of massive stars having strong stellar winds at the same evolutionary epoch, whereas in 30 Dor the collective effort of winds and supernovae is capable of initiating and maintaining large interstellar bubbles and supershells. The shell masses range from a few hundred to several thousand solar masses. The mechanical energy requirements are around 1051 erg. Supernovae, and possibly stellar winds, are the likely sources of energy. If 30 Dor were observed at 10 Mpc, only HST could perform spatially resolved imaging and spectroscopy of R136, which would subtend an angle of only 0.05 arcsec.

Figure 2. Ultraviolet spectral region of NGC 1741. Left: Observed spectrum taken with the GHRS. Right: Synthetic spectrum computed for a 5 Myr old instantaneous starburst following a Salpeter IMF. The main diagnostic lines of Si IV and C IV agree.

Starburst galaxies
Detailed spectroscopic studies of large numbers of individual stars are no longer feasible beyond a few Mpc:
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ST ScI Newsletter Science Institute ·HST Space Telescope · Astronomy with Newslette r

Starburst Distance

from page 3

even the visually brightest star in Trumpler 14, HD 93129A, would appear at 1 Mpc as a V=18.6 star (assuming no extinction). The closest examples of the so-called starburst galaxy class are found in this distance range. Starburst galaxies form large numbers of massive stars that have a global effect on the galaxy, both in terms of their radiant and their mechanical energy output. What would 30 Dor and the LMC look like if they were a factor of 1000 farther away? Figure 1 gives the answer. NGC 1741 is a luminous irregular at a distance of 50 Mpc, highly reminiscent of the LMC when seen on wide-angle photographs. It has two luminous H II regions at the NW end of the bar. The bar population is largely unresolved. NGC 1741 contains about 103 highly evolved Wolf-Rayet stars -- more WR stars than known individually in all galaxies of the Local Group combined.

Individual stars (or even clusters) can no longer be investigated at distances of ~50 Mpc and beyond. Stellar and nebular properties are derived from the integrated light. A GHRS spectrum of the starburst region containing the WR population is shown in Figure 2 (left). The most conspicuous stellar lines are C IV, Si IV, N V, and He II. These lines have broad absorptions and/or emissions due to their origin in stellar winds from hot stars and permit a study of the hotstar population. A theoretical spectrum is also shown in this figure (right). It was calculated with a population of massive stars following a Salpeter IMF for masses above ~15 MSun (lower mass stars may also be present), and extending up to ~100 MSun; about 104 O-type stars are inferred from the ultraviolet luminosity.

Star formation at the edge of the universe
We conclude with a brief look at the most distant star-forming galaxies known. They are the endpoint of our cosmic voyage, which began in the Carina star forming region. Few

starburst galaxies have been studied in detail at large redshifts. Detecting galaxies in their initial star-formation stage (often called primeval or protogalaxies) has been a major goal in observational cosmology during the past years. This goal has eluded almost everybody until very recently, when several groups independently announced the detection of promising candidate galaxies forming stars at high redshift. In all cases the presence of ultraviolet stellar-wind lines, such as those seen in Figure 2, was taken as evidence for massive stars. The Hubble Deep Field (HDF) is an HST program to image an indistinguished field at high Galactic latitude in four passbands as deeply possible. The image shows a plethora of distant field galaxies, many of them having complex and disturbed morphologies. Spectroscopy of these star-forming candidates is required for analysis, an effort reaching the limits of our current observational capabilities. Possibly these observations will find the first generation of massive stars ever formed in the universe.

HST Recent Release: A Survey of Quasar Host Galaxies
Quasars reside in a variety of galaxies, from normal to highly disturbed. When seen through ground-based telescopes, these compact, enigmatic light sources resemble stars, yet they are billions of light-years away and several hundred billion times brighter than normal stars. The following Hubble Space Telescope images show examples of different home sites of all quasars. But all the sites must provide the fuel to power these unique light beacons. Astronomers believe that a quasar turns on when a massive black hole at the nucleus of a galaxy feeds on gas and stars. As the matter falls into the black hole, intense radiation is emitted. Eventually, the black hole will stop emitting radiation once it consumes all nearby matter. Then it needs debris from a collision of galaxies or another process to provide more fuel.

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January 199 7

HST Programs and Observations

Duration of Cycle 7
R. Williams and P. Stanley
Most HST proposal/observing cycles have been approximately one year long. In fact, the community has expressed a desire for the Institute to try to fix established dates during the calendar year for the receipt of proposals, and we have adhered to this for the past two cycles. This becomes impractical in cycles for which there are servicing missions because of the fact that each servicing mission requires a 4-month period, called Servicing Mission Observatory Verification (SMOV), when the telescope and its new instruments and components must be brought on-line, thoroughly checked out, and initially calibrated. Maintaining the one year length of a cycle would therefore require that the science program of the cycle last only 8 months. A shortened science period for Cycle 7 would have required submission of proposals for Cycle 8 before much experience had been acquired with the new instruments STIS and NICMOS. We considered a shortened science program for Cycle 7 but the quality of proposals received and the oversubscription rate were so high that we felt it compelling to have Cycle 7 consist of a full year of science observations. With the nominal 4-month period devoted to SMOV following the SM2 launch, this leads to a slip in our schedule for Cycle 8. Cycle 7 science observations should commence in July, 1997, as we complete the schedule of Cycle 6 programs. The Call for Proposals for Cycle 8 is now scheduled to be issued in October, 1997, with a proposal receipt date in early February, 1998. We realize that the calendar used for Cycles 6 and 7 may have been more convenient for the writing and submission of proposals, but we have tried to establish new calendar dates for the proposal process in Cycle 8 that will also not be too inconvenient. Cycle 8 observing will run from November, 1998, to November, 1999.

Panel and TAC Members for Cycle 7
Telescope Allocation Committee
Mike Shull, Chair

TAC At-Large Members
TAC AT-Large Members Art Davidsen - JHU Anne Kinney - STScI Bohdan Paczynski - Princeton Anneila Sargent - Caltech Don York - U. Chicago

PANELS
AGN 1

The following individuals served on the Cycle 7 Time Assignment Committee. We thank them for their help in the difficult job of selecting the HST science program.

Bradley Peterson - Ohio State (Panel Chair) Buell Jannuzi - NOAO/KPNO Grzegorz Madejski - GSFC Simon Morris - Dominion Astro. Obs. John Mulchaey - Carnegie Obs. Marcia Rieke - U.Arizona/Steward Thomas Soifer - Keck Observatory Clive Tadhunter - U. of Sheffield, UK Mark Whittle - U.Virginia

AGN 2
Rachel Webster - U. of Melbourne, Australia (Panel Chair) Michael Eracleous - U. of CA, Berkeley Gary Ferland - U. of Kentucky Mauro Giavalisco - Carnegie Obs. Frederick Hamann - U. of CA George Rieke - U. Arizona Steward Obs Joseph Shields - U. of Ohio Stefan Wagner - Heidelberg, MPA, Germany Donald Schneider - Penn State Beverley Wills - U. of Texas

Binary Stars
Jonathan Grindlay - Harvard Obs (Panel Chair) Paul Hertz - Naval Research Lab Janusz Kaluzny - Warsaw Anthony Moffat - U. of Montreal Mirek Plavec - U. of CA Paula Szkody - U. of Washington Marten van Kerkwijk - Caltech Janet Wood - Keele University

Clusters
Richard Mushotzky - GSFC (Panel Chair) Thomas Broadhurst - UC, Berkeley Jack Burns - NMSU Hans Hippelein - MPIA Tod Lauer - KPNO/NOAO Gerard Luppino - University of Hawaii Ann Zabludoff - Carnegie Obs.
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ST ScI Newsletter SciencePrograms andNObservations Space Telescope · HST Institute · ewslette r

PANELS

from page 5

Cosmology
George Efstathiou - U. of Oxford-Astrophysics (Panel Chair) Arif Babul - NYU Lennox Cowie - U. of Hawaii Andrew Hamilton - U. of Colorado Saul Perlmutter - LBL Robert Schommer - CTIO Peter Schneider - MPI Joe Silk - U. of CA, Berkeley Gary Wegner - Dartmouth College

Edward Fitzpatrick - Princeton Thomas Henning - ESA (Jena, Germany) Elizabeth Lada - U. of Florida Manuel Peimbert - UNAM

Quasar Absorption Line
Craig Hogan - U. of Washington (Panel Chair) Stefano Cristiani - ESA Observatory Dipadova James Lowenthal - Lick Obs Michael Rauch - Caltech Gregory Shields - U. Texas Lisa Storrie-Lombardi - Carnegie Observatory Art Wolfe - U. of CA, San Diego

Cool Stars
Andrea Dupree - SAO (Panel Chair) Howard Bond - STScI David Gray - U. of Western Ontario Philip Ianna - U. Virginia Ruth Peterson - Lick Observatory Catherine Pilachowski - KPNO/NOAO Neill Reid - Caltech Klaus Strassmeier - Vienna U., Austria Nicholas Suntzeff - CTIO

Stellar Ejecta
Robert Fesen - Dartmouth College (Panel Chair) Dave Arnett - U. of Arizona, Steward Observatory Bruce Balick - U. of Washington William Blair - JHU Claes Fransson - ESA, Stockholm Obs Bruce Hrivnak - Valparaiso U. Margaret Meixner - U. of Illinois John Raymond - Cfa Steve Shore - IN U.

Galaxies 1
Rob Kennicutt - U. of Arizona, Steward Obs. (Panel Chair) Jay Frogel - OSU Jeff Kenney - Yale David Merritt - Rutgers Colin Norman - JHU/STScI Renzo Sancisi - Kapteyn Astronomical Ins Francois Schweizer - Carnegie/DTM Jacqueline van Gorkom - Columbia Dennis Zaritsky - UCSC

Stellar Populations
Gerard Gilmore - Inst of Astr. (Panel Chair) Bruce Carney - U. of North Carolina Eileen Friel - National Science Foundation Douglas Geisler - NOAO/KPNO Deidre Hunter - Lowell Obs Chris Sneden - U. Texas at Austin Donald Terndrup - Ohio State Monica Tosi - ESA, Bologna Obs Bruce Twarog - U. of Kansas

Galaxies 2
Rosie Wyse - JHU (Panel Chair) Stephane Charlot - IAP William Keel - U. Alabama Carmelle Robert - U. Laval Barbara Ryden - OSU John Salzer - Wesleyan David Sanders - U. Hawaii David Van Buren - Caltech

Solar System
Philip Nicholson - Cornell University (Panel Chair) Gordon Bjoraker - GSFC Wendy Calvin - USGS Flagstaff Anita Cochran - U. of Texas Jean Claude Gerard - U. of Liege Al Harris - JPL Hal Weaver - JHU Robert West - JPL

Hot Stars
Rolf-Peter Kudritzki - U. of Munich-I for A&A (Panel Chair) Bruce Bohannan - KPNO/NOAO Martin Cohen - U. of CA, Berkeley John Drilling - Louisiana St Mario Livio - STScI Wolf-Rainer Hamann - U. of Potsdam Gloria Koenigsberger - UNAM Rex Saffer - Villanova

Young Stars and Circumstellar Material
Charles Lada - SAO (Panel Chair) Fred Adams - U. of Michigan Mary Barsony - UC Riverside Chas Beichman - IPAC Ian Gatley - NOAO Bill Herbst - Wesleyan University Anne-Marie LaGrange - Grenoble Observatory Erick Young - U. of Arizona

Instellar Medium
Carl Heiles - U. of CA, Berkeley (Panel Chair) Donald Cox - U. WI-Madison

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AGN 1
Archival Study of Nuclear Morphology in Interactive Galaxies Testing the Supermassive Black Hole Paradigm in Nearby Radio-Quiet AGNs Spectra to Constrain the Dynamics of Clouds in the Narrow-Line Region of NGC 1068 Continuous Ultraviolet Monitoring of NGC 3516 The connection between the obscuring torus and masing disk in H_2O Megamasers Snapshot survey of the B2 sample of radio galaxies An Archival Study of Nearby, Low-Luminosity Active Galactic Nuclei Measuring Black Hole Masses in Broad-Lined AGNs Kinematics of the HAlpha Nuclear Disk in M81: A Search for a MBH in the Nearest LINER Intrinsic UV and X-ray Absorption in QSOs High Resolution IR Imaging Survey (IRIS) of the Centers of the Nearest Active Galaxies The Relation Between Quasar Luminosity and Host Galaxy Mass The Fueling of Active Nuclei: A NICMOS Snapshot Survey of Seyfert and Normal Galaxies The Nature of Nuclear Activity in Nearby Galaxies A New Technique for Photometry of Low Luminosity AGNs Using HST Reference Images Infrared imaging and polarimetry observations of the obscured nucleus of Centaurus A The nature of the compact infrared core sources in powerful FRII radio galaxies STIS Spectroscopy of Markarian 78 Kinematics of the Helical Jets in the Seyfert Galaxy ESO428-G14 The Molecular Torus and Ionized Gas in the Circinus Galaxy

Approved Observing Programs for Cycle 7

Borne Bower Cecil Edelson Falcke Fanti Filippenko Filippenko Ford Hamann Malkan McLeod Mulchaey Rix Romanishin Schreier Tadhunter Whittle Wilson Wilson

Hughes STX National Optical Astronomy Observatories University of North Carolina at Chapel Hill University of Iowa Astronomy Department, University of Maryland Universita di Bologna University of California, Berkeley University of California, Berkeley Johns Hopkins University Center for Astrophysics & Space Science University of California Smithsonian Astrophysical Observatory The Observatories of the Carnegie Institution of Washington Steward Observatory University of Oklahoma Space Telescope Science Institute University of Sheffield University of Virginia Astronomy Department University of Maryland

Continued

AGN 2

2 Secular Changes in the Jet of M87 High Redshift Reflection Nebulae The Stellar Content of Powerful Radio Galaxies: A NICMOS Survey of 0.8 < z < 1.8 3CR Sources Kinematics of Gaseous Disks in the Nuclei of Liners with Compact Flat Spectrum Radio Sources The cosmological evolution of quasar host galaxies FeII Emission in Quasars Testing the Nature of Type 2 LINERs Using UV Spectroscopy The Unusual Absorption Line System of PG 2302+029 -- Ejected or Intervening? Chemical Abundances in QSO Broad Absorption Line Regions A Search for Broad Absorption Lines in Narrow-Line Seyfert 1 Galaxies NICMOS Imaging Survey of Distant Radio Galaxies: Ellipticals at z > 2 ? NICMOS Observations of PKS1413+135 Quasar Candidates in the Hubble Deep Field Witnessing the Birth of Radio Galaxies: WFPC & NICMOS Observations of CSOs Polarization mapping of the infrared emission from the jet in M87 Microarcsecond Imaging of a Gravitationally Lensed QSO: 2237+0305 HST WFPC2 Observations of MilliJansky Radio Sources from the FIRST Survey

Biretta Chambers Dey Dressel Dunlop Ferland Ho Jannuzi Junkkarinen Leighly McCarthy McHardy Osmer Stocke Thomson Webster White

Space Telescope Science Institute Institute for Astronomy Kitt Peak National Observatory RJH Scientific, Inc. University of Edinburgh University of Kentucky Center for Astrophysics National Optical Astronomy Observatories University of California, San Diego Columbia University The Carnegie Observatories University of Southampton The Ohio State University University of Colorado, Boulder University of Hertfordshire University of Melbourne Space Telescope Science Institute

Binary Stars
The nature of the bright Supersoft X-ray Source RX J 0019+21 WFPC2 Observations of Astrophysically Important Visual Binaries High-Speed UV Spectroscopy of the Ultracompact Binary 4U 1626--67/KZ TrA Narrow band imaging of jets and bipolar outflows from symbiotic stars High resolution UV spectroscopy of the extra-ordinary central star of Abell 35 The Dense Core of M30

Beuermann Bond Chakrabarty Corradi Drew Edmonds

Universitaets-Sternwarte Goettingen Space Telescope Science Institute Massachusetts Institute of Technology Instituto de Astrofisica de Canarias Astrophysics Group, Imperial College Space Telescope Science Institute

January 1997

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ST ScI Newsletter
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HST Programs and Observations

Espey Grindlay Harrison Kaper Knigge Margon Margon McClintock Rousseau Sams Schmidt Shara Shara Still Teeseling Vrtilek

The Johns Hopkins University Harvard University New Mexico State University European Southern Observatory Space Telescope Science Institute University of Washington University of Washington Smithsonian Astrophysical Observatory Universitaets-Sternwarte Goettingen Max Planck Insitute fuer Astrophysics Steward Observatory, University of Arizona Space Telescope Science Institute Space Telescope Science Institute University of St. Andrews Universitaets-Sternwarte Goettingen Smithsonian Astrophysical Observatory

Improved Emission Line Diagnostics of Symbiotic Stars Deep Survey for CVs and Compact Binaries in the Collapsed Core Cluster NGC6397 The Distances to Dwarf Novae, and the Calibration of the Technique of Infrared Spectroscopic Parallax Raman scattering and X-ray ionization in LMC X-4, Cyg X-1, and LMC X-1 Demystifying the SW Sex stars The Nature of Two New Optical Counterparts of Globular Cluster X-ray Sources Intense Galactic X-ray Sources in Crowded Fields Black Hole A0620-00 and Advection-Dominated Accretion UV Cyclotron Spectroscopy of the High-Field Polar UZ Fornacis Jet Polarization and Emission lines in the Galactic Microquasar GRS1915+105 Probing the 230 MG Accreting Magnetic White Dwarf in AR Ursae Majoris Recovery and Characterization of Old Novae in the Globular Clusters M80 and M14 An Archival Search for Erupting Dwarf Novae in Globular Clusters High resolution imaging of magnetically-propelled ejecta from the cataclysmic variable AE Aqr van Ultraviolet spectroscopy of the supersoft X-ray source RX J0439.8-6809 High Resolution Ultraviolet Spectroscopy of Hercules X-1/HZ Herculis

Approved Observing Programs for Cycle 7

Clusters of Galaxies

Continued

Blandford Broadhurst Dalcanton Donahue Fabian Ferguson Franx Fruchter Keel Mackie Owen Ratnatunga Rosati Saunders Squires

Caltech Astronomy Dept The Observatories of the Carnegie Institution of Washington Space Telescope Science Institute Institute of Astronomy, University of Cambridge Space Telescope Science Institute Kapteyn Institute Space Telescope Science Institute University of Alabama Smithsonian Institution Astrophysical Observatory NRAO Carnegie Mellon University Johns Hopkins University Mullard Radio Astronomy Observatory Center for Particle Astrophysics

Galaxy Masses from Cluster Arcs Modeling Cluster Mass Distributions Elliptical Galaxy Evolution at High Redshift: IR Imaging of 100 Distant Clusters Warm Molecular Hydrogen in Cluster Cooling Flow Nebulae The central mass profile in the lowest redshift cluster lenses Intergalactic Stars in the Virgo Cluster Fundamental Plane, Morphology-Density Relation, and Lensing in the z=0.83 Cluster MS1054--03 The Luminosity Function and Evolution of Rich Clusters to z ~ 1.0 The Age and Content of a (Proto)Galaxy Cluster at z=2.39 Structural Properties of Brightest Cluster Galaxies in the HST Archive The Impact of Cluster Substructure on Galaxies: A Case Study in Abell 2125 Quantitative Morphology of Cluster Galaxies : Evolutionary Trends Probing Low Density Cluster Environments at Moderate-to-High Redshifts The most powerful gravitational lens Dark Matter Distribution in A2218 from Gravitational Lensing

Cosmology
Improved Hubble Constant from the 0957+561 Gravitational Lens Spheroidal Galaxy Evolution The Nature of Faint, Blue, I-K>4 Galaxies: Age or Dust? A study of the gravitational lensing potential in MG 0414+0534 Deep UV Imaging of the Hubble Deep Field IR Surface Brightness Fluctuations of Fornax Cluster Galaxies High-resolution IR and optical imaging of the fields around a large sample of z > 4.5 quasars The Nature of Galaxies in the HDF from HST Structural and Keck Kinematical Measurements NICMOS observations of JVAS/CLASS gravitational lenses Determination of the Extragalactic Distance Scale Spatial Structures and Masses of Faint Field Galaxies Survey of Gravitational Lenses as Cosmological Tools Calibration of the Cepheid P-L Relation with Observations of the Maser-Host Galaxy NGC 4258 NICMOS Extragalactic Parallel Grism Survey The Nature of Red Outlier Galaxies: Age vs Dust

Bernstein Broadhurst Davis Falco Ferguson Graham Hu Illingworth Jackson Kennicutt Koo Lehar Maoz McCarthy Moustakas

University of Michigan University of California, Berkeley University of California Smithsonian Astrophysical Observatory Space Telescope Science Institute University of California, Berkeley University of Hawaii, Institute for Astronomy Lick Observatory, University of California, Santa Cruz Jodrell Bank, University of Manchester Steward Observatory Lick Observatory, University of California, Santa Cruz Smithsonian Astrophysical Observatory University of California, Berkeley The Carnegie Observatories University of California


Moller Perlmutter Readhead Sandage Schmidt Shara Smail Tanvir Tonry Tsvetanov Turner Windhorst Yahil Zepf

Space Telescope Science Institute Lawrence Berkeley Laboratory California Institute of Technology Observatories of the Carnegie Institution of Washington Mount Stromlo and Siding Spring Observatories Space Telescope Science Institue Durham University Institute of Astronomy Institute for Astronomy Johns Hopkins University Princeton University Observatory Arizona State University, Dept. of Physics & Astronomy University at Stony Brook University of California, Berkeley

STIS images of 48 damped LyAlpha galaxies Cosmological Parameters Omega and Lambda from High-Redshift Type Ia Supernovae NICMOS observations of the gravitational lens 1608+656 Calibration of Nearby Type Ia Supernovae as Standard Candles: The Next Three-Year Step The Hubble Diagram for Distant Supernovae: Measuring Cosmic Deceleration and Global Curvature The nature of the extragalactic UV background An Unbiased Redshift Survey of Ultra-Faint Galaxies The distance to M96 from H-band Cepheid observations The SBF Hubble Diagram The Surface Brightness Fluctuations and Globular Cluster Populations of Virgo Ellipticals Gravitational Lensing Enhanced NICMOS Imagery of a Young, Rapidly Evolving Faint Blue Galaxy NICMOS imaging of MuJy radio sources with R>= 29: The birth of AGN in pregalactic objects at z>=6-10? Image Reconstruction and Photometry of the Hubble Deep Field Determining Peculiar Motions by Observing Cepheids at 3,000 km/s

Approved Observing Programs for Cycle 7

Cool Stars

Continued

Basri Bennett Boehm-Vitense Bookbinder Brown Clayton Dupree Edvardsson Evans Franz Golimowski Henry Jordan Leinert Linsky Lopez Parsons Peterson Peterson Peterson Reid

University of California University of Colorado Astronomy Department, University of Washington Smithsonian Astrophysical Observatory California Institute of Technology Louisiana State University Smithsonian Astrophysical Observatory Uppsala Astronomical Observatory Smithsonian Astrophysical Observatory Lowell Observatory Johns Hopkins University Space Telescope Science Institute University of Oxford, Department of Physics (Theoretical Physics Max-Planck-Institut fuer Astronomie JILA Observatoire de la Cote d'Azur Computer Sciences Corporation Astrophysical Advances Astrophysical Advances Astrophysical Advances California Institute of Technology

Ultraviolet Line Eclipses by Extra-Solar Planets The 1997/98 Eclipse of VV Cephei Chromospheres and transition layers in Hyades and Pleiades F stars Eclipse Mapping of the Touchstone Binary System YY Gem A Search for Zodiacal Dust around Bright Nearby Stars Dust Formation Around R Coronae