Hubble Cycle 18 Proposal Selection

Claus Leitherer,, & Daniel Apai,


When the Cycle 18 Call for Proposals was released on December 9, 2009, Cycle 17 was well underway, and the newly installed—as well as the prior-generation—instruments on Hubble had been calibrated and characterized after Servicing Mission 4. Unlike the situation during the previous Call for Proposals, astronomers could prepare their proposals and estimate resources knowing the instruments were in place and had already been checked out. The Advanced Camera for Surveys (ACS), Cosmic Origins Spectrograph (COS), Fine Guidance Sensor (FGS), Space Telescope Imaging Spectrograph (STIS), and Wide Field Camera 3 (WFC3) were all close to nominal operation and were available for Hubble observing proposals in Cycle 18. The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) was available for proposers as well. However, when the Call for Proposals was issued, the NICMOS cooling system had not yet been restarted, and NICMOS was inactive. The decision on when the cooling system would be restarted had not yet been made. Nevertheless, the proposers were advised to assume NICMOS would be available during Cycle 18.

The Phase I deadline for Cycle 18 was February 26, 2010. While some proposals were received well in advance of the deadline, most proposals arrived on the very last day, with an ever-increasing number piling up during the final minutes before 8 p.m. Eastern time. As many astronomers living on the East Coast may remember, that particular day was one of many when snowstorms hit the area and caused a snow emergency. The Institute was actually operating under liberal leave on February 26. Luckily, with the help of our dedicated staff, the proposal submission process was completed without major hiccups. In the end, we received 1,051 proposals. The final tally was not known until a few days after the deadline because of duplicate submissions and some withdrawals.

Peer Review Process

Hubble proposals are reviewed by members of the international astronomical community, who serve on various panels organized by science category and proposal size. Large proposals in all science categories are reviewed by the time allocation committee (TAC). All other programs are assigned to panels according to their science category.

The process of selecting the panelists begins with the selection of the Chair about six months prior to the proposal deadline. Neta Bahcall (Princeton) served as Chair of the Cycle 18 TAC. Next, we selected the chairs of the panels, who also serve as members of the TAC. In addition, there are three at-large TAC members, with broad expertise, who review proposals as assigned. The recruitment of panel members is usually completed about two months prior to the proposal deadline. The goal is to have a healthy mix of experienced, senior panelists, as well as younger panel members, at the postdoctoral level. Other important considerations are gender balance and representation of ESA and other countries. For Cycle 18, we anticipated high proposal pressure, and initially invited ~130 scientists from the community as panelists or TAC members. In the event, the proposal pressure exceeded expectations, and additional panelists were recruited—and a new panel constituted—after the Phase I deadline. The final Cycle 18 assessment process involved close to 150 panelists and TAC members, which is the largest number ever to participate in a Hubble proposal review.

In order to minimize the workload for each panelist, we increased the number of panels from 12 in Cycle 17 to 14 in Cycle 18. Of these, two panels were for the solar system and exoplanets, two for cool stars and star formation, three for hot stars and stellar populations, three for galaxies, two for active galactic nuclei (AGN) and the intergalactic medium (IGM), and two panels for cosmology.

Each topical set of panels served as “mirrors,” so that proposals could be transferred to a mirror panel if necessitated by conflicts.

Ideally, one would like to have all panels be of equal size, but in practice this was not feasible, because different science categories have varying numbers of proposals.  In addition, the meeting room sizes vary and impose a limit on the panel size. In Cycle 18, the panels had between 8 and 13 members; the TAC totaled 18.

The proposal review took place during the week of 17–21 May, 2010. As in Cycle 17, we held the Cycle 18 proposal review in the buildings of the Institute and the Physics & Astronomy department of the Johns Hopkins University (JHU). JHU kindly offered the additional space. Most panelists preferred the campus location to the offsite conference center where we held the review in some of the previous years.

The TAC and the panels in Cycle 18 had 2,600 orbits available for allocation. Of these, 2,000 were made available to the panels, and 600 to the TAC. This allocation is smaller than in the previous cycle, due to the allocation of orbits to the (1) Multi-Cycle Treasury Program, (2) remaining COS GTO orbits, and (3) unexecuted Cycle 16 and 17 programs. The oversubscription ratio was 9:1 by orbits, which translated into a proposal acceptance rate of one out of six.

The acceptance rate for archival research was about one out of three, similar to the long-term average.

Quite a few observing proposals fell into the medium category (40–99 orbits), making them quite expensive, but still too small to fall into the large category (100+ orbits). In prior cycles, a “subsidy” was given to medium proposals, meaning that—if such a proposal were approved—the panel would be charged fewer orbits than the number requested. The subsidy is taken from a central pool. In Cycle 18, because of the large oversubscription and the relatively smaller number of orbits available to the panels, there was a concern that—even with the subsidy available—the panels would be hesitant to support any of the medium proposals. To guarantee the approval of at least some scientifically outstanding, medium proposals, 300 orbits from the panel allocation were set aside for them, in lieu of a panel subsidy. Out of this pool, the panel chairs of each set of mirror panels could allocate orbits to their top-ranked medium proposals. We have requested feedback from the panelists on the merits of this approach, in order to develop the process to be used for Cycle 19.

Our policy for handling conflicts of interest remained unchanged from Cycle 17, when we defined co-investigators (Co-Is) who are close collaborators to be minor conflicts. Similarly, institutional conflicts were considered to be minor.  When a minor conflict arises, the panelist may, at the chair’s discretion, participate in the proposal discussion—but must not cast a vote. Striking a balance between minimizing conflicts of interest and maximizing the expertise of a panel is becoming increasingly challenging as collaborations expand and proposals grow in size. We found our rules led to a healthier discussion in the panels, with no evidence for bias.

Summary of Cycle 18 Results

ProposalsRequestedApproved% AcceptedESA
General Observer  872 14616.7% 3020.5%
Snapshot   51   917.6%  333.3%
Archival Research   75  2634.7%  0
AR Legacy   10   220.0%  0
Theory   43  1330.2%  0
Total 1051 19618.6% 3316.8%
Primary Orbits23096 2578*11.2%38214.8%
*Does not include 16 Calibration orbits (9 Prime + 7 Internals)


The 1,051 proposals submitted in Cycle 18 included 872 general observer (GO), 51 snapshot (SNAP), 75 archival, 10 legacy archival (AR), and 43 theory programs. Six hundred orbits were made available for proposals reviewed by the TAC, and 2,000 for the proposals reviewed by the 14 panels. Three hundred out of 2,000 orbits were reserved for medium-sized proposals (see table with summary of Cycle 18 results). The Cycle 18 panels and TAC recommended approving 196 programs, including 146 GO, 3 SNAP, 28 AR and legacy archival, and 13 theory programs. The recommended theory programs include one GO and five AR calibration programs. Two joint ChandraHubble, two joint National Optical Astronomy Observatories–Hubble, and one joint Spitzer–Hubble programs were awarded time by the panels.

Eight large and treasury programs were recommended by the TAC.

As a reflection of Hubble’s new capabilities, Cycle 18 has seen one of the highest oversubscriptions in the history of the telescope. About nine times more orbits were requested than were available, and six times more proposals were submitted than approved. Hubble is a joint NASA–European Space Agency (ESA) mission. ESA scientists were principal investigators (PIs) on 33 of the 196 accepted proposals, accounting for 14.8% of the orbits allocated and 16.8% of the proposals.

For Cycle 18, the TAC and the panels recommended 59% of the GO prime orbits—excluding orbits of parallel observations—for spectroscopy and 41% for imaging. WFC3 is the most widely used instrument in prime mode, with a usage of 42%, followed by STIS 26%, COS 23%, ACS 9%, and FGS <1%. If parallel orbits are included in the count, the statistics are WFC3 42%, ACS 24%, STIS 18%, COS 16%, and FGS <0.1%.

Instrument Statistics

ConfigurationModePrime %Coordinated
Parallel %
ment Prime Usage
Prime + Coordinated Parallel Usage
ACS/SBCImaging 3.0% 0.0% 2.4% 0.0% 0.0%
ACS/WFCImaging 5.7%46.6%13.9%21.1%26.7%
ACS/WFCRamp Filter 0.2% 0.0% 0.2% 8.9%24.2% 0.0% 0.0%
ACS/WFCSpectroscopy 0.0%38.4% 7.7% 0.0% 0.0%
COS/FUVSpectroscopy20.8% 0.0%16.6% 0.0%29.4%
COS/NUVImaging 0.0% 0.0% 0.0%23.1%18.4% 0.0% 0.0%
COS/NUVSpectroscopy 2.3% 0.0% 1.8% 0.0% 0.0%
FGSPOS 0.2% 0.0% 0.2% 0.2% 0.2% 0.0% 0.0%
FGSTRANS 0.0% 0.0% 0.0% 0.0% 0.0%
NIC1Imaging 0.0% 0.0% 0.0% 0.0% 0.0%
NIC2Imaging 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0%
NIC3Imaging 0.0% 0.0% 0.0% 0.0% 0.0%
NIC3Spectroscopy 0.0% 0.0% 0.0% 0.0% 0.0%
STIS/CCDImaging 4.7% 0.0% 3.7% 0.0% 0.0%
STIS/CCDSpectroscopy 5.5% 0.0% 4.4% 0.0% 0.0%
STIS/FUVImaging 0.2% 0.0% 0.2%26.2%20.9% 0.0% 0.0%
STIS/FUVSpectroscopy10.1% 0.0% 8.1% 0.0%19.4%
STIS/NUVImaging 0.3% 0.0% 0.2% 0.0% 0.0%
STIS/NUVSpectroscopy 5.4% 0.0% 4.3% 0.0% 0.0%
WFC3/IRImaging 6.8% 0.0% 5.5%50.0%14.8%
WFC3/IRSpectroscopy19.9% 0.0%15.9%41.7%36.3%28.9% 0.0%
WFC3/UVISImaging14.9%15.0%15.0% 0.0% 9.7%
WFC3/UVISSpectroscopy 0.0% 0.0% 0.0% 0.0% 0.0%
Approved GO Prime
Total GO Usage
FGS 0.2%FGS<0.1%
NICMOS  0.0%

The TAC and panels recommended using less than 1.5% of the available orbits for observations by NICMOS. This indicates that NICMOS still provides unique scientific capabilities on Hubble; however, those programs represent a small contribution to the overall science program. Given these circumstances, and because the restart of the NICMOS cooling system requires resources—including a significant number of orbits—the Hubble project, the Institute, and NASA Headquarters agreed that NICMOS would not be available for science in Cycle 18. Consequently, no new NICMOS observations were approved.




Science Program

The TAC and the panels recommended a broad range of science categories, from nearby, solar-system objects to galaxies at redshifts of z ~ 8, and utilizing the power of all Hubble instruments.

One TAC-approved program aims to collect STIS ultraviolet echelle spectra for a diverse sample of cool stars, to build an advanced spectral library for astrophysical exploration. This library will allow the detection of rare species in sharp-lined F stars, properties and kinematics of local interstellar clouds, and the dynamics of chromospheres, coronae, and winds of cool stars.  Rapid public release of the data will enable many other investigations by a much wider community, no doubt continuing for decades to come.

An approved Hubble exoplanet program is scientifically complementary to Spitzer, Kepler, and COROT (Convection, ROtation and planetary Transits) results. The PI and CoIs will obtain transmission spectroscopy of the 1.4-micron water band in a sample of 13 planets, using the G141 grism of WFC3.  Among the abundant molecules, only water absorbs at this wavelength, and a measurement of water abundance will remove ambiguities in the Spitzer results.

IGM science is represented by new COS G130M and G160M observations of quasi-stellar objects, which will probe the gaseous halos of dwarf galaxies well inside their virial radii. Using sensitive absorption-line measurements, the program will map the halos of low-luminosity galaxies over impact parameter to distances of 15−150 kpc. These observations will directly constrain the content and kinematics of accreting and outflowing material and will be highly relevant to the study of galaxies at high z, where shallow halo are the norm.

Submitted/Approved Orbits by Science Category


A 250-orbit program will provide rest-frame optical spectra for a complete sample of 9,000 galaxies at redshifts 1 < z < 3.5. It was during this period that most star formation took place, the number density of quasars peaked, the first galaxies stopped forming stars, and the structural regularity that we see in galaxies today must have emerged. The survey area will cover a subset of the fields included in the CANDELS Multi-Cycle Treasury program, amplifying the scientific returns from that program.

One pure-parallel program will use WFC3’s unique power for slitless spectroscopy to measure cosmic star formation across its peak epoch. Grism spectroscopy in deep and shallow fields will detect a sample of 2,000–3,000 emission-line galaxies in the unexplored redshift region around z = 2–3 and search Ly-α emitters at z > 5.5. A second pure-parallel program aims to search for Lyman-break galaxies at z ≈ 6−8. As the survey fields are random and completely uncorrelated, the number counts will be little affected by biases caused by statistical fluctuations. Hence, we will be able to obtain the best constraint yet on the bright-end of the luminosity function in that redshift range.

Two Legacy AR programs were recommended: one will perform a complete and consistent recalibration of all raw NICMOS polarimetric, science-imaging data in the MAST archive. The goal is to enable science deferred or previously unachieved. This program will create high-level, analysis-quality data sets with quantitative error estimates, which will be entered into the MAST for public dissemination. The second AR program will create a comprehensive, uniformly processed, well documented, and searchable collection of solar-system data obtained with WFPC2. The “planet pipeline” will populate the image headers with information unique to planetary data, and produce a science-ready collection of data.

Proposals by Country

Australia110Korea  4  1
Belgium 41Mexico  2  0
Canada155Netherlands 11  2
Chile 70Poland  2  0
China 10Portugal  2  0
Czech Republic 10Russia  2  0
Denmark 61South Africa  6  1
Finland 10Spain 11  0
France161Sweden  6  1
Germany385Switzerland  6  1
Greece 10Taiwan  2  0
India 20UK 65 16
Ireland 20USA788154
Israel 52
Italy283ESA Proposals198 33
Japan 52


Numerous Institute and JHU personnel contributed to the Cycle 18 review process, both up front and behind the scenes. Within the Science Mission Office, Daniel Apai, Neill Reid, Rachel Somerville, and Bob Williams were responsible for selecting the panelists, assigning the proposals to panels and panelists, and providing roving oversight during the review. Brett Blacker received, organized, and distributed the proposals, oversaw the proposal database, distributed the results, and prepared the statistical summaries and figures presented here. Craig Hollinshead, John Kaylor, Greg Masci, and other members of the Information Technology Services Division were responsible for developing and implementing the web-based review system. The Instruments Division and the Hubble Mission Office were responsible for technical support, and almost 30 Institute postdocs and staff provided panel support: Elizabeth Barker, Luigi Bedin, Andrea Bellini, Tiffany Borders, Azalee Bostroem, Christine Chen, Susana Deustua, Lisa Frattare, Parviz Ghavamian, David Golimowski, Aaron Grocholski, Bethan James, Pey-Lian Lim, Kevin Lindsay, Knox Long, Jack MacConnell, Ed Nelan, Sami-Matias Niemi, Cristina Oliveira, Abhijith Rajan, Michael Regan, Tony Roman, Kailash Sahu, Tony Sohn, Galina Soutchkova, Chris Thom, Tatjana Tomovic, Michael Wolfe, and Brian York. Logistical support was a particular challenge this year because of the record number of panelists. Darlene Spencer provided the overall supervision, assisted by: Karen Petro, Ronda Washington, Karyn Keidel, Roz Baxter, Tracy Bennett, Rolanda Taylor, Flory Hill, Samantha Pryce, Laura Bucklew, Ana-Maria Valenzuela, Dixie Shipley, Cheryl Schmidt, Ran Freeman, Tania Laguerre, Robin Auer, Ciera Hall, and Loretta Willers.

Assistance on the JHU side was provided by Brian Schriver, Pam Carmen, and Norma Berry, while Greg Pabst, Jeff Nesbitt, Mike Venturella, Frankie Schultz, Alford Kizer, Bill Franz, Yvette Taft, Mike Sharp, Grover Williams, Rob Levine, Phyllis Smith, James Walston, and Chad Smith (copy center) supplied Institute facilities support. Val Schnader, Ray Beaser, Paula Sessa, Karen Debelius, Margie Cook, Joe Hann, Vickie Bowersox, Lisa Kleinwort, Terry McCormack, and Dorothy Brown in the Business Resources Center, as well as John Eisenhamer and Pam Jeffries (Office of Public Outreach) were also involved in the process. Catering was provided by Irena Stein and her staff of Café Azafran.

Cycle 18: TAC and Panel Members

TAC Members
Neta BahcallPrinceton UniversityTAC Chair
Michael EracleousThe Pennsylvania State UniversityTAC At Large Member
John HuchraHarvard UniversityTAC At Large Member
Jim PringleUniversity of CambridgeTAC At Large Member
Extra Galactic Panel Members
Roberto AbrahamUniversity of TorontoExgal Panel Chair
Lee ArmusCalifornia Institute of TechnologyExtra Galactic
Daniel BatcheldorFlorida Institute of TechnologyExtra Galactic
Eric BellUniversity of MichiganExgal Panel Chair
Misty BentzUniversity of California - IrvineExtra Galactic
Michael BlantonNew York UniversityExtra Galactic
Marusa BradacUniversity of California - DavisExtra Galactic
Jean BrodieUniversity of California - Santa CruzExtra Galactic
Jane CharltonThe Pennsylvania State UniversityExgal Panel Chair
Christopher ChurchillNew Mexico State UniversityExtra Galactic
Emanuele DaddiCEA/DSM/DAPNIA/Service d'AstrophysiqueExtra Galactic
Charles DanforthUniversity of Colorado at BoulderExtra Galactic
Gabriella De Lucia INAF, Osservatorio Astronomico di Trieste Extra Galactic
Duilia de MelloNASA Goddard Space Flight CenterExtra Galactic
Tiziana Di MatteoCarnegie Mellon UniversityExtra Galactic
Megan DonahueMichigan State UniversityExgal Panel Chair
Reginald DufourRice UniversityExtra Galactic
Derek FoxThe Pennsylvania State UniversityExtra Galactic
Johan Fynbo University of Copenhagen, Niels Bohr Institute Extra Galactic
Martin GaskellUniversity of Texas at AustinExtra Galactic
Mark GirouxEast Tennessee State UniversityExtra Galactic
Genevieve GravesUniversity of California - BerkeleyExtra Galactic
Jenny GreenePrinceton UniversityExtra Galactic
Raja GuhathakurtaUniversity of California - Santa CruzExtra Galactic
Knud Jahnke Max-Planck-Institut für Astronomie, Heidelberg Extra Galactic
Lisa KewleyUniversity of HawaiiExtra Galactic
Juna KollmeierCarnegie Institution of WashingtonExtra Galactic
Chryssa KouveliotouNASA Marshall Space Flight CenterExtra Galactic
Mariska KriekPrinceton UniversityExtra Galactic
Ivo LabbeCarnegie Institution of WashingtonExtra Galactic
Tod LauerNational Optical Astronomy ObservatoriesExtra Galactic
Karen LeighlyUniversity of Oklahoma Norman CampusExtra Galactic
Jennifer LotzNational Optical Astronomy ObservatoriesExtra Galactic
Lauren MacArthurDominion Astrophysical ObservatoryExtra Galactic
Sangeeta MalhotraArizona State UniversityExtra Galactic
Paul MartiniThe Ohio State University Research FoundationExtra Galactic
Karin Menendez-DelmestreCarnegie Institution of WashingtonExtra Galactic
Leonidas MoustakasJet Propulsion LaboratoryExtra Galactic
Priyamvada NatarajanYale UniversityExtra Galactic
Roderik OverzierMax-Planck-Institut für AstrophysikExtra Galactic
Michael PahreSmithsonian Institution Astrophysical ObservatoryExtra Galactic
Chien PengDominion Astrophysical ObservatoryExtra Galactic
Eric PengPeking UniversityExtra Galactic
Laura Pentericci INAF, Osservatorio Astronomico di Roma Extra Galactic
Maria PollettaIstituto Nazionale di AstrofisicaExtra Galactic
Cristina PopescuUniversity of Central LancashireExtra Galactic
Moire PrescottUniversity of California - Santa BarbaraExtra Galactic
Marina RejkubaEuropean Southern Observatory - GermanyExtra Galactic
Jane RigbyCarnegie Institution of WashingtonExtra Galactic
Sara SalimbeniUniversity of MassachusettsExtra Galactic
Dave SandersUniversity of HawaiiExgal Panel Chair
Claudia ScarlataCalifornia Institute of TechnologyExtra Galactic
Daniel SchaererObservatoire de GenèveExtra Galactic
Ricardo Schiavon Gemini Observatory, Northern Operations Extra Galactic
Jennifer ScottTowson UniversityExtra Galactic
Nick ScovilleCalifornia Institute of TechnologyExtra Galactic
Alice ShapleyUniversity of California - Los AngelesExgal Panel Chair
AliciaSoderbergHarvard UniversityExtra Galactic
Geneviève SoucailObservatoire Midi-PyrénéesExtra Galactic
John StockeUniversity of Colorado at BoulderExtra Galactic
Tommaso TreuUniversity of California - Santa BarbaraExtra Galactic
Todd TrippUniversity of MassachusettsExtra Galactic
Marianne Vestergaard University of Copenhagen, Niels Bohr Institute Extra Galactic
Nicole VogtNew Mexico State UniversityExtra Galactic
David WeinbergThe Ohio State University Research FoundationExtra Galactic
Ben WeinerUniversity of ArizonaExtra Galactic
Liliya WilliamsUniversity of Minnesota - Twin CitiesExtra Galactic
Rogier WindhorstArizona State UniversityExgal Panel Chair
Guy WortheyWashington State UniversityExtra Galactic
Sukyoung YiYonsei UniversityExtra Galactic
Nadia ZakamskaInstitute for Advanced StudyExtra Galactic
Galactic Panel Members
Thomas AyresUniversity of Colorado at BoulderGalactic
Francesca BacciottiOsservatorio Astrofisico di ArcetriGalactic
Isabelle BaraffeUniversity of ExeterGalactic
Beatriz BarbuyUniversidade de São PauloGalactic
Arjan Bik Max-Planck-Institut für Astronomie, HeidelbergGalactic
Robert BlumNational Optical Astronomy ObservatoriesGalactic
Fabio BresolinUniversity of HawaiiGalactic
Cesar BriceñoCentro de Investigaciones de AstronomíaGalactic
Sean BrittainClemson UniversityGalactic
Adam BurgasserUniversity of California - San DiegoGalactic Panel Chair
Paul CrowtherUniversity of SheffieldGalactic Panel Chair
Andrew DolphinRaytheon CompanyGalactic
Gaspard DucheneUniversity of California - BerkeleyGalactic
Andrea DupreeSmithsonian Institution Astrophysical ObservatoryGalactic
Annette FergusonRoyal Observatory EdinburghGalactic
Peter GarnavichUniversity of Notre DameGalactic
Marla GehaYale UniversityGalactic
William HarrisMcMaster UniversityGalactic
Suzanne HawleyUniversity of WashingtonGalactic Panel Chair
Sara HeapNASA Goddard Space Flight CenterGalactic
Alexander HegerUniversity of Minnesota - Twin CitiesGalactic
Ulrike HeiterUppsala Astronomical ObservatoryGalactic
Gregory HerczegMax-Planck-Institut für extraterrestrische PhysikGalactic
Jon HoltzmanNew Mexico State UniversityGalactic
Joseph HoraSmithsonian Institution Astrophysical ObservatoryGalactic
Ivan HubenyUniversity of ArizonaGalactic
Edward JenkinsPrinceton UniversityGalactic Panel Chair
Saurabh JhaRutgers the State University of New JerseyGalactic
Kelsey JohnsonThe University of VirginiaGalactic
Lex KaperUniversiteit van AmsterdamGalactic
Christian KniggeUniversity of SouthamptonGalactic
John LattanzioMonash UniversityGalactic
Jeffrey LinskyUniversity of Colorado at BoulderGalactic
Kevin LuhmanThe Pennsylvania State UniversityGalactic
Massimo MarengoIowa State UniversityGalactic
Stephan McCandlissThe Johns Hopkins UniversityGalactic
Maryam ModjazUniversity of California - BerkeleyGalactic
Patrick MorrisCalifornia Institute of TechnologyGalactic
Bob O'DellVanderbilt UniversityGalactic
Anne PellerinTexas A&M Research FoundationGalactic
Klaus PontoppidanCalifornia Institute of TechnologyGalactic
Michael RichUniversity of California - Los AngelesGalactic
Harvey RicherUniversity of British ColumbiaGalactic
Abhijit SahaNational Optical Astronomy ObservatoryGalactic
Richard ShawNational Optical Astronomy ObservatoryGalactic
Edward SionVillanova UniversityGalactic
Verne SmithNational Optical Astronomy ObservatoriesGalactic
Nicholas SterlingMichigan State UniversityGalactic
Susan TerebeyCalifornia State University - Los AngelesGalactic
Saeqa VrtilekSmithsonian Institution Astrophysical ObservatoryGalactic
Lifan WangTexas A&M Research FoundationGalactic
Dennis ZaritskyUniversity of ArizonaGalactic Panel Chair
Planetary Panel Members
David ArdilaCalifornia Institute of TechnologyPlanetary
Marc BuieSouthwest Research InstitutePlanetary
John DebesNASA Goddard Space Flight CenterPlanetary
Drake DemingNASA Goddard Space Flight CenterPlanetary
Paul FeldmanThe Johns Hopkins UniversityPlanetary Panel Chair
Alan FitzsimmonsQueen's UniversityPlanetary
Erika GibbUniversity of Missouri - St. LouisPlanetary
James GrahamUniversity of California - BerkeleyPlanetary Panel Chair
Caitlin GriffithUniversity of ArizonaPlanetary
Amanda HendrixJet Propulsion LaboratoryPlanetary
Michael JuraUniversity of California - Los AngelesPlanetary
William MerlineSouthwest Research InstitutePlanetary
Glenn OrtonJet Propulsion LaboratoryPlanetary
Marshall PerrinUniversity of California - Los AngelesPlanetary
Aki RobergeNASA Goddard Space Flight CenterPlanetary
Scott SheppardCarnegie Institution of WashingtonPlanetary
David SingUniversity of ExeterPlanetary
Mark SwainJet Propulsion LaboratoryPlanetary
Anne VerbiscerThe University of VirginiaPlanetary
Cycle 18 Approved Observing Proposals

Cycle 18 Approved Observing Proposals


Cycle 18 Approved Observing Proposals (continued)

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Cycle 18 Approved Observing Proposals (concluded)

Cycle 18 Approved Observing Proposals (concluded)