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The Outer Planets Assessment Group (OPAG) was established by NASA in late 2004 to identify scientific priorities and pathways for exploration in the outer solar system. The group consists of a 15-person steering committee, which actively solicits input from the scientific community and reports its findings to NASA Headquarters. OPAG provides input to NASA but does not make recommendations.

OPAG Charter

OPAG is NASA's community-based forum designed to provide science input for planning and prioritizing outer planet exploration activities for the next several decades. It is chartered by NASA's Solar System Exploration Division and reports its findings at meetings of the Solar System Exploration Sub-Committee of the NASA Space Science Advisory Committee. Open to all interested scientists, OPAG regularly evaluates outer solar system exploration goals, objectives, investigations and required measurements on the basis of the widest possible community outreach.

Updated 2018 draft goals document now available for community feedback:

Revised 2018 draft goals document
Updated September 5, 2018

Upcoming Meetings

Meeting Announcement Update:

The Spring OPAG Meeting is scheduled and confirmed for April 23–24, 2019, in Washington, DC., NASA HQ, Webb Auditorium.


Please note, Committee Members do not need to register, they have been registered by meeting conveners. Non-committee members (AKA everyone else, the general community) have to register, see the link below.

OPAG Registration Page is Now Opened

The Registration Page is now opened for the upcoming OPAG meeting on April 23–24 at NASA HQ. Registration is required for all attendees except for the steering committee members.


Meeting number: 906 630 696
Meeting password: !Qazxsw2
Toll Number 800-857-7362 Participant passcode 3096983
(same #'s for both days)

Recent Meetings

March 13, 2019

OPAG Special Findings

September 11–12, 2018
Langham Huntington Pasadena
Pasadena, California

Agenda and Presentations
Posters, Talks, and Science Nuggets

OPAG 2018 

Tuesday, September 11, 2018 | 8:00 am Pacific Standard Time | 12 hours 50 minutes | Not started
Recurrence: Every day, from Tuesday, September 11, 2018, to Wednesday, September 12, 2018

Meeting Link:
Meeting number: 997 689 640
Meeting password: W@lc0m31 

Audio connection:
Toll Free Number: 800-857-9688
Participant Passcode: 7331611​

*On the day of the meeting, copy and paste the link to your browser if clicking on it does not work.​
*Please use the link below to test your connection prior to the meeting.* ​

Poster Instructions

The posters sizes for the upcoming meeting are 4’x4’ and if you really want you can do 4’ high by 8’ wide (but let Pat Beauchamp know because she will count this as two posters).  When you have your poster ready, please send it to Pat Beauchamp and CC Nina Pretty so they can be put on the OPAG website. Before your poster session you will have a 2 minute lightning talk about your poster. For this you can send Pat a SINGLE PowerPoint Chart (not a copy of your poster) or you can just talk to it without one, but please let her know ahead of time which you prefer.

Early Career Participant Support Available for NASA Outer Planets Assessment Group Meeting

NASA’s Outer Planets Assessment Group will provide travel grants for a limited number of interested Early Career participants to attend the OPAG meeting September 11–12 in Pasadena, CA. OPAG plays a key role in sculpting the planetary science community’s input into NASA activities for outer planets science and exploration. Thus it is critical for Early Career scientists to attend these meetings both to learn how NASA and Planetary Science programs operate and to represent the community that will work on OPAG-relevant projects in the coming decade. Selected individuals will present a poster at the meeting on a topic of their choosing. Interested graduate students, postdocs, and other Early Career scientists (within 5 years of PhD/MS/BS) should submit a one page letter of interest and a CV to by August 20, 2018. Recipients will be notified by August 24.  For more information, email Britney Schmidt at the address above.

February 21–22 and February 23, 2018 Technology Forum
Hampton, Virginia

Agenda and Presentations
Posters and Science Nuggets

February 23, 2018
OPAG Technology Forum

September 6–7, 2017
The Seaside Forum, Scripps Institute of Oceanography
La Jolla, CA

February 22–23, 2017
Hosted by Georgia Tech
The Georgian Terrace

August 11–12, 2016
Flagstaff, Arizona
There will also be a ROW meeting on August 10, in Flagstaff.

February 1–2, 2016
Southwest Research Institute (SWRI)
San Antonio, Texas

August 24–26, 2015
Laurel, MD

March 18, 2015 LPSC OPAG Townhall Presentations with notes

Europa Lander Instrument PEA

Special OPAG Steering Committee Finding, May 26, 2017

NASA released "Community Announcement Regarding Europa Lander Instrument Investigation Program Element Appendix” on May 17, 2017 (see  This announcement included a surprising statement regarding participation by JPL: "…the following organizations will be prohibited from submitting proposals in response to the PEA: the Jet Propulsion Laboratory (JPL), Cornell Technical Services (CTS), and Arctic Slope Regional Corporation.  These organizations will provide substantial support to the development and execution of the PEA.  In particular, JPL personnel will support the development of the AO and documents in the Program Library, assess the accommodation of proposed instrument investigations, provide technical support to teams during Step 2, and participate in site visits during the Step-2 evaluation.”  The OPAG steering committee is concerned about the potential exclusion of JPL scientists and instrument technology experts who have spent decades preparing for a life-detection mission such as Europa Lander.  We urge NASA to proceed in a way that does not increase risk to Europa Lander science by excluding key capabilities.  We note that NASA has funded much highly relevant work at JPL via R&A programs and the Astrobiology Institute, and instrument technology development via MatISSE, PICASSO, COLDtech, and other programs.  Excluding the knowledge gained from such efforts would be counterproductive.


THE OPAG Steering Committee urges NASA to proceed with Europa Lander instrument and science team selections in a way that results in the best possible science return. 

OPAG Science Goals Document 2015

Draft for Community Comment

Scientific Goals for Exploration of the Outer Solar System

Outer solar system exploration motivation

Europa Studies

2013 Europa Clipper Update
Robert Pappalardo, Jet Propulsion Laboratory, California Institute of Technology
Brain Cooke, Applied Physics Laboratory, Johns Hopkins University

"Science Potential from a Europa Lander" in Astrobiology
Read the definitive, peer-reviewed version of the Science Definition Team's report on "Science Potential from a Europa Lander" in the journal Astrobiology.

Older Europa Mission Studies

Europa Lander Science Definition Team (SDT)  

Indication of Interest