• Korea has installed the DARP (Dual Anonymous Review Process) system from 25B semester. All Gemini proposals requesting time from the US, CA, BR, or AR have been following the DARP policy since 2021. For the Korean Gemini Users, 1yr (or plus) of a grace period (i.e. no penalty to proposals that do not meet the DARP policy) will be given so that they can be well trained/prepared for the DARP system. Korea will fully adopt the DARP policy in the proposal review process from 26B or 27A.

  Here is a brief summary for the DARP policy:

  Guideline for PIs

  • Enter information of the proposing team with the Phase I Tool (PIT) as usual.
  • Use the FT specific template.
  • The proposal template has been updated to be compliant with DARP starting on Feb 1, 2021
  • Avoid mentioning names and affiliations of the team in the PDF attachment that could be used to identify the proposing team.
  • Avoid claiming ownership of past work. (E.g., “my successful Gemini program in the previous semester (GS-18A-xxx)”, or “our analysis shown in Doe et al. 2020…”)
  • Including text in proposals discussing previous use of Gemini is ok, as long as that work is not referenced and program IDs are not listed.
  • Cite references in passive third person, e.g., “Analysis shown in Doe et al. 2020”, including references to data and software.
  • Do describe the proposed work, e.g., “We propose to do the following…”, or “We will measure the effects of …”
  • Unpublished work can be referred to as “obtained in private communication” or “from private consultation”.

  Guideline for Reviewers

  • Accept the assigned proposals based on abstracts whether you can provide an unbiased review or not.
  • Review proposals solely based on the scientific merit of what is proposed.
  • Do not spend any time attempting to identify the PI or the team. Even if you think you know, you can be wrong.
  • Utilize neutral pronouns (they/the PI/the team) when you write comments.
  • Flag the proposals that have not been sufficiently anonymized but DO NOT penalize them by lowering grades. (The FT support team will check the flagged proposals and send any violations to the Gemini Directorate for review.) 

• All proposals to use Gemini in 2026A must use the 2026A Phase I template. When preparing PDF attachments, please follow the proposals template font size requirements in all cases, and avoid using smaller fonts in all sections of Gemini proposals (including in figures and tables).

• Classical mode observing is offered in semester 2026A for facility instruments only. PIs requesting Classical observing must state in their technical justification how the observations could be done in queue mode (with remote eavesdropping for data quality assessment and decision making)

• Priority Visitor (PV) mode is offered at both Gemini North and Gemini South. If circumstances preclude having people on-site, programs awarded PV time will revert to queue mode. PIs requesting PV observing mode must state in their technical justification how the observations could be done in queue mode (with remote eavesdropping for data quality assessment and decision making). The "Bring One, Get One" Student Observer Support Program remains unavailable for semester 26A.

• Rapid Target of Opportunity (rToO) Proposals: These can be accommodated for most instruments and their modes (and this includes non-LGS modes), subject to instrument availability on the dates upon which observations are triggered.

• Timing Windows. In the “Scheduling” section of the PIT, provide all timing windows throughout the semester that are associated with your targets (timing windows added after the proposal submission deadline will normally be rejected). Timing windows must be specified by indicating the start time in UT, followed by the duration (in hours and minutes); for example: 2025-11-08 05:38:00 04:25. Ensure the format follows: yyyy-mm-dd hh:mm:ss hh:mm. We strongly recommend to organize the TW in a table format.

• Monitoring observations. In the “Scheduling” section of the PIT, For each target, provide the Number of visits per Night, the cadence (in hours), and the total number of nights (or epochs) for each target. We strongly recommend to organize this information in a table format.

• GMOS On-Sky Arcs: GMOS baseline arcs are now taken on sky mixed with the science observations. For details on the updated GMOS arc baseline policy please see this page.

• Gemini North Engineering Time:

  • No shutdown is planned for 26A. The installation of a laser guide star equipment for the future GNAO-LGSF tasks will require two extra weeks, with dates yet to be determined.

• Gemini North - Beginning in Semester 26A, both IGRINS-2 and MAROON-X will share the bottom port. If demand and program approval trends mirror those of Semester 25B, we anticipate that observing time on the bottom port will be approximately evenly distributed between the two instruments. This arrangement may affect programs requesting observations with timing windows as well as monitoring observations, and RV observations.

• Gemini North - NIFS, NIRI & GRACES: No longer offered.

• Gemini South is expected to be closed for the last 12 nights of semester 26A (Jul 15 - 31).

• Gemini South - GHOST PIs to receive reduced data products: The US NGO, in collaboration with Gemini, will offer reduced spectra for GHOST programs from all partner countries. The reduced files will be available through the Gemini Observatory Archive, together with the raw data. More information can be found here.

• Gemini South - IGRINS and IQUEYE not offered in 26A

• Gemini South - GSAOI and GeMS are being decommissioned and will no longer be offered in this and future semesters. 

• The Gemini Observatory Graduate Student Visitor Program is temporarily suspended for semester 26A. Details of the Graduate Student Visitor program are available here.

Proposals for time on Gemini, and for time on Subaru via the Gemini-Subaru time exchange program, must use the Gemini Phase I Tool (PIT). Latex and Word templates are available to create PDF attachments that include the science and technical cases, and investigator information. The template has been revised to enable the anonymous review process, and to make proposal requirements uniform across the partners. Two attachments are required for the proposal so that team information can be separated from the science case. PIs with targets that can be observed from either Gemini North or South (e.g. equatorial targets to be observed with one of the GMOS instruments) can request time with both instruments; in that case the time with each instrument should be halved, and the Observatory will update the observation times when targets are scheduled.

All Gemini proposals requesting time from the US, CA, BR, KR or AR must be anonymized. Proposals which do not meet the guidelines will be penalised. This applies to proposals requesting time only from these partners, as well as joint proposals requesting time from multiple participants that include any of these partners. This requirement applies whether it is the PI or a co-I that has the relevant partner affiliation.

Specific Timing Windows: In order to maximize the chances of completing observations with timing windows, 26A proposals should:

• Provide a clear indication of the need for timing windows at Phase 1. Please provide all timing windows throughout the semester that are associated with your targets. Any additional timing windows requested by PIs after the proposal submission deadline has passed will not normally be approved. Timing windows should be entered in the "Scheduling" section of the PIT. Timing windows must be specified by indicating the start time in UT, followed by the duration (in hours); for example: 2025-11-08 05:38 04.25. Ensure the format follows: yyyy-mm-dd hh:mm hh.hh..

• Use observing constraints appropriate to the expected lunar conditions. For example, if the only timing window for your proposal occurs during dark time, you should make sure to choose SB20 or SB50 as appropriate. Similarly, if you have a monitoring program with a cadence of a few days, you should define two sets of observations in the PIT, one with SBAny for bright time and another alternative option with SB50 for dark time (to allow for possible changes in sky brightness within the usable period).

Additional options in the Time Requests module in the PIT are available for semester 2026A:

• The Gemini 2026A Phase 1 Tool includes options to specify that the proposal is for the AEON multi-telescope-facility system. 

• Also in the 2026A Time Requests module, there is an option to identify proposals which have synergies with James Webb Space Telescope science. The goal for providing this proposal category is to encourage development of science programs that benefit from a combination of Gemini and JWST observations.

Time for baseline partner calibrations is automatically added to the total time requested for each target in the PIT. You should continue to include the time associated with overheads (acquisition time, readout time, etc). The ITC output gives overhead estimates. 'Alopeke and Zorro PIs should include program time for PSF standards if they need them. IGRINS-2 users will have several options in the “Night Basecal Time” in PIT; it will be possible to choose between default standards (1 standard every 1.5h), one telluric, two tellurics, or no standard.

Target of opportunity proposals must include all instrument configurations needed for the proposed science case, at Phase 1. This enables automatic creation of templates, and avoids errors at Phase 2.

Gemini North:

** Due to limited sky availability during the semester, GMOS MOS programs requiring pre-imaging should not have targets in this region, and other programs with targets in this region should not require a large amount of time, or have strict timing or observing constraints.

Gemini South:

** Due to limited sky availability during the semester, GMOS and FLAMINGOS-2 MOS programs requiring pre-imaging should not have targets in this region, and other programs with targets in this region should not require a large amount of time, or have strict timing or observing constraints. 

Gemini North:

Gemini South: