| 2004A-PA-03B-0089 | Bowen, Tripp, Heckman, York | G II QSO Absorption Systems: Galaxy Halos or Metal Enriched IGM? |
| 2004A-PA-03B-0370 | Kulkarni, York, Lauroesch, Khare, Crotts, Nakamura | The Evolution of Metals and Dust in Damped Lyman-Alpha Quasar Absorbers |
| 2004A-PA-04A-0299 | Forrest, Hoffman, Furlan, Watson, Uchida | Mid-Infrared Observations of Protostellar and Protoplanetary Disks in Taurus |
| 2004A-SAO-1 | Szentgyorgyi, Caldwell, Furesz, G. Williams | Continued Commissioning of the Hectochelle |
| 2004A-SAO-2 | Fabricant, Caldwell, McLeod | Bringing Hectospec to Full Performance |
| 2004A-SAO-3 | McLeod, Conroy | MegaCam Engineering |
| 2004A-SAO-4 | Noyes, Szentgyorgyi, Latham, Nisenson, Korzennik, G. Williams | Engineering Test of Hectochelle Precise Radial Velocity Capabilities |
| 2004A-SAO-5 | Geller, Fabricant, Kurtz, Freedman, Dell'Antonio, Wittman, Wilson | Mapping the Matter Distribution in the Universe |
| 2004A-SAO-7 | Kirshner, Matheson, Challis, Hicken | Late-Time Supernova Light Curves |
| 2004A-SAO-8 | Spahr, Holman, Osip | Physical Characterization of Small Solar System Objects |
| 2004A-SAO-9 | Holman, Grav | The Size Distribution of Kuiper Belt Bodies |
| 2004A-SAO-10 | Hartmann, Stauffer, Szentgyorgyi | The Pleiades: from Testing to Science |
| 2004A-SAO-11 | Vikhlinin, Quintana, Hornstrup, Burenin | 400 Square Degrees Distant Cluster Survey |
| 2004A-SAO-12 | Murray, Jones, Forman, Green, Kenter, Vikhlinin, Fazio, Pahre, Huchra, Ashby, Falco, Caldwell, Kochanek, Eisenstein, Fan, Impey, Papovich, M. Rieke, Dey, Jannuzi, Najita, Shields, McNamara, Eisenhardt | The AGN and Galaxy Evolution Survey (AGES) |
| 2004A-SAO-14 | Hartmann, Stauffer, Rebull, Szentgyorgyi | NGC 2264: Kinematics and Membership of a Key Young Cluster |
| 2004A-SAO-15 | van den Berg, Verbunt, Tagliaferri, Belloni, Homan | Looking for Compact Accreting Binaries among the Chandra Sources of the Old Open Cluster M67 |
| 2004A-SAO-18 | Hartmann, Calvet, Briceqo, Stauffer, Rebull, Szentgyorgyi | The Orion Nebula Region: Cluster in Formation |
| 2004A-SAO-19 | Metcalfe, Liebert, K. Williams, Munn, Harris, Dahn, von Hippel, Winget | Improved Luminosity Function of Cool White Dwarfs from the SDSS |
| 2004A-SAO-20 | Green, Marble, Eriksen | Verifying a Unique Lens Candidate: A Radio Loud BALQSO at z = 1.71 |
| 2004A-SAO-23 | Marsden, Sykes, Lebofsky, Hinz, Close, Hoffmann, Kenworthy, Brusa, Miller | Thermal AO Mapping of the Surface of Ceres |
| 2004A-SAO-29 | Wang, Willner, Smith, Ashby, Surace<./td> | Near Infrared Imaging of Star Forming Interacting Galaxies |
| 2004A-SAO-30 | Latham, Torres, Szentgyorgyi, Morse, T. Brown | Kepler Target Selection |
| 2004A-SAO-31 | Mallen-Ornelas, Kewley, Ellison | Are QSO Absorption Line Systems Good Indicators of Cosmic Metal Abundance? |
| 2004A-SAO-32 | Latham, Torres, Mathieu | Open Cluster Studies |
| 2004A-UAO-L25 | Fan, Strauss, Jiang | A Survey of Luminous Quasars at z ~ 6 in the Northern Galactic Cap |
| 2004A-UAO-L55 | Bechtold, Jannuzi, Morris | The IGM and the Distribution of Galaxies at z ~ 1 |
| 2004A-UAO-L58 | Eisenstein, Cool, Fan, Impey, Papovich, M. Rieke, Zaritsky, Zehavi | A Spectroscopic Survey of the NOAO Deep/Wide Bootes Field |
| 2004A-UAO-S16 | Liebert, Eisenstein | A Search for Ultra-Low Mass White Dwarfs |
| 2004A-UAO-S18 | Skillman, Hewett, Irwin | Chemical Abundances in the Newly Discovered Nearby PN Hewett-1 |
| 2004A-UAO-S19 | Skillman | Physical Conditions in I Zw 18 |
| 2004A-UAO-S23 | Fan, Strauss, Vestergaard | Spectroscopy of New z ~ 5 Quasars: Evolution of the High-Redshift Quasar Population |
| 2004A-UAO-S28 | Fan, Eisenstein, McCarthy | Exploratory AO Imaging of Quasars with Natural Guide Stars |
| 2004A-UAO-S29 | Impey, Prescott | Quasars in the COSMOS/HST Treasury Field |
| 2004A-UAO-S31 | K. Williams, Bolte | The White Dwarf Cooling Sequence in Old Open Clusters |
| 2004A-UAO-S32 | Olszewski, Mateo, Walker | A New Era of Mapping Dark Matter in Dwarf Spheroidal Galaxies |
| 2004A-UAO-S34 | Oppenheimer, Bieging, Close, Hinz, Kenworthy, Hoffmann, Lloyd-Hart | Mid-IR AO Imaging of Proto-Planetary Nebulae |
| 2004A-UAO-S37 | McCarthy | ARIES Engineering |
| 2004A-UAO-S49 | Wagner, Starrfield, Bond | Probing the Circumstellar Environment of the Luminous Variable Star V838 Mon |
| 2004A-UAO-S51 | Biller, Close, Bieging, Hinz, Hoffmann, Miller, Brusa, Lloyd-Hart, Kenworthy | High Strehl, Mid-IR AO Imaging of AGB and Post-AGB Stars with Molecular Reservoirs: Direct Imaging of the Disks around the Red Rectangle, BM Gem, RV Boo, X Her |
| 2004A-UAO-S52 | Biller, Close, McCarthy, Nielsen, Miller, Brusa, Hinz, Lloyd-Hart, Mamajek, Kenworthy | Direct Detection of Young Extrasolar Planets with Simultaneous Differential Imaging and the MMT AO System |
| 2004A-UAO-S56 | Cui, Bechtold, Fan | The Influence of Quasars and Galaxies on the Intergalactic Medium |
| 2004A-UAO-S59 | Liu, Hinz, Hoffmann, Silverstone | An Exozodiacal Dust Survey with Nulling Interferometry |
| 2004A-UAO-S65 | Potter, Brusa, Close, Fisher, Hinz, Kenworthy, Lloyd-Hart, McCarthy, Miller | Dynamical Mass Determination of the Binary Brown Dwarf System HD130948bc through Astrometry with the MMT/AO System |
| 2004A-UAO-S73 | Egami, G. Rieke, Papovich, Rigby, Dole | Deep Near-IR Imaging of the SIRTF Lensing Cluster Survey Sample |
| 2004A-UAO-S74 | Thuan, Izotov | Cosmological Studies with Blue Compact Dwarf Galaxies |
| 2004A-UAO-S75 | Papovich, Dickinson, Barton, Giavalisco | Spectroscopy of Candidate Lensed Lyman Break Galaxies |
| 2004A-UAO-S77 | Hinz, Miller, Brusa, Lloyd-Hart, Close Kenworthy | Refinement and Characterization of the MMT AO System |
