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2023 LLP Call for Proposals

Content owned by Sandy Leggett


Important Dates

  • December 7, 2022 LLP Proposal Cycle Announcement of Opportunity
  • February 13, 9am HST, 2023 - Letters of Intent Due
  • March 1, 2023 - 2023B regular semester Call for Proposals released
  • April 1, 2023 - 2023 LLP Proposals deadline 
  • Late-April, 2023 - Large Program Time Allocation Committee meets
  • Mid-June, 2023 - 2023B telescope schedule and LLP proposal cycle announcements

This page contains information specific to the 2023 Large and Long Program proposal cycle.
General information on the LLP proposal process, including proposal format and requirements, can be found on the
LLP Proposal Process webpage.

Time Available for New Gemini LLPs

The estimated time available for new Gemini LLPs is provided in the table below. The time available is estimated as 200 hours less any previously allocated LLP time. The numbers in the Table are estimates only, the exact time available will depend on instrument commissioning, engineering, campaign science, limited-term partnerships, etc. as well as the status of ongoing LLP programs.

Estimated Time Available for new LLPs in Hours
Site Band 2023B 2024A 2024B 2025A 2025B 2026A
North 1 55.0 100.0 100.0 100.0 100.0 100.0
2 31.0 29.0 100.0 100.0 100.0 100.0
South 1 100.0 100.0 100.0 100.0 100.0 100.0
2 45.5 44.6 100.0 100.0 100.0 100.0

Target and Observing Constraint Restrictions

An individual LLP need not request a balanced program across North/South, RA range, observing conditions, etc. However, the ensemble of approved LLPs must not overly impinge on other observing programs. Therefore, the ensemble of approved LPs should not exceed ~25% of any relevant parameter, such as hemisphere, RA range, and observing condition bins. See this page for further information on observing condition constraints.

LLPs will also be subject to general semester target availability restrictions, as published in the general call for proposals for each semester.

Instrument Availability

The instruments available for new LLPs are listed below, along with any particular restrictions of note. Successful LLPs may also be limited by the semester-specific instrument availability restrictions announced with each semesters regular Call for Proposals.

Gemini North

  • GMOS-N: Available for use 2023B-2026A. See special note on GMOS MOS proposals below.
  • GNIRS: Available for use 2023B-2026A,  in imaging (through keyhole), long slit, cross-dispersed and IFU modes. Adaptive optics is expected to be available for all modes. Prospective PIs must check for updates on the IFUs before submitting their full proposal.
  • Altair: Available for use 2023B-2026A.
  • Alopeke: Available for use 2023B-2026A.
  • MAROON-X: Available for use for three semesters only, 2023B-2024B, as the current agreement only extends through 2024B and conversion to a facility instrument is still under study.

Gemini South

  • GMOS-S: Available for use 2023B-2026A. See special note on GMOS MOS proposals below.
  • FLAMINGOS-2: Available for use 2023B-2026A, in imaging, longslit and MOS modes.
  • GSAOI/GEMS: Available for use 2023B-2026A.
  • GHOST: UPDATED MARCH 2023: GHOST will not be available for regular science in 23B. Commissioning is not complete and instrument sensitivities are not documented. For these reasons it is recommended that LLP proposals using GHOST are postponed until 2024.
  • Zorro: Available for use 2023B-2026A.
  • IGRINS: Available at Gemini South for use in semesters 2023B and 2024A only.
2023 LLP Call for Proposals | Gemini Observatory


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