Cycle 13 Call for Proposals (1 Dec 2025 - 15 May 2026)
Proposal Deadline (extended): 11:59 Hours (Bangkok Time), 29 August 2025
Start of the Cycle for the 2.4-meter TNT is postponed to 1 Dec 2025 due to repairs required for the dome shutter and M4 encoder.
The TNO-1m will still be offered starting 21 Oct 2025.
Proposals are invited to request time on the 2.4m Thai National Telescope (TNT) and on the 1m telescope at the Thai National Observatory (TNO) (TNO-1m).
- Cycle 13: for the 2.4m TNT (public) and the TNO-1m (public)
Key Dates:
CfP opens: 21 July 2025
Deadline: 29 August 2025 11:59 AM Bangkok Time
Observation Period:
1 December 2025 - 15 May 2026 (TNT 2.4-m)
21 October 2025 - 15 May 2026 (TNO 1-m)
The proposal must be submitted in ENGLISH ONLY.
Eligible proposers
The call for the 2.4m TNT and TNO-1m is open to all Thai and Internationally affiliated astronomers.
Proposals with at least ONE Thai-affiliated CoI (or PI) are strongly encouraged. Non-Thai PI proposals can be submitted in the usual way. However, if a Thai-affiliated and a non-Thai-affiliated proposal are ranked equally, preference will be given to the Thai-affiliated proposal.
Furthermore, in deciding on proposal rankings, the Time Allocation Committee (TAC) will take into account the publication record and the impact of the proposers with previous NARIT telescope time allocations.
The proposals will be reviewed by a panel of professional astronomers and will be ranked on the basis of their scientific scores by TAC nominated by the NARIT Director. The technical feasibility of the proposals will be reviewed by the NARIT Division of Observatory Operations (DOO).
What's new in this Cycle?
- Short & Long Term Designation
We are preparing a data archive to make all observations publicly available after some proprietary period. The investigator can designate their observing program as short or long term. For a short term project, the embargo time will be 2 years start from June 1 after the end of the cycle. For a long term project, the applicant will have to state the period of the project but could not exceed 5 years. The embargo time will be the entirety of the project period plus two years after the June 1st of the year the project ends.
There will also be an option to for you to allow all calibration data from your program to be immediately public. Lastly, you will be able to suggest up to three reviewers in the proposal.
- Instrument-specific updates
- Low-Resolution Spectrograph (LRS) is offered for scientific uses on a “shared-risk” basis. For more information regarding the instrumentation, please refer to LRS Mark III specification, contact: Krittapas Chanchaiworawit, krittapas@narit.or.th)
- For observation/details of ULTRASPEC at TNT, contact: Puji Irawati (puji.irawati@narit.or.th)
- MRES: New 1k CCD and fiber were installed during Cycle 12, allowing for a larger wavelength coverage in the blue, and no wavelength coverage gaps between orders blue of 858 nm. For more information on MRES, including the exposure time estimation and data reduction pipeline, please refer to MRES Instrument Description Document.
For observation/details of MRES, contact: David Mkrtichian (davidmkrt@gmail.com)
- ARC 4K: For observation/details of this instrument, contact: proposal@narit.or.th
- A commercial spectrograph (eShel) is now available for TNO-1m. Please contact somsawat@narit.or.th if you are interested in using this instrument. In addition, in the “Instrumentation” section of your proposal, please select “Visitor Instrument” and specify “eShel”.
- Multiple instruments
Applicants of TNO Cycle 13 can request multiple instruments in their proposal. The desired instrument(s) can be selected in the instrument section of the online submission form.
Note that the applicants have to provide detailed information on the need of using multiple instruments for their proposals.
Important Notes
- The TAC will be putting a strong emphasis on the past publication record of PIs and projects previously allocated time on the TNT during the past cycles. The proposer of an application under these conditions must take good care in filling out sections C) and G) in the "Description of the proposed project" of the online form.
- Observation requirements in section B) must be provided as complete as possible. Proposals that fail to provide the observation requirements may be rejected.
- There will be no DOO staff to assist with the observation of the TNO-1m.
- Observers are expected to contact NARIT staff to prepare for their visit at least one month in advance of their run. They are expected to cover their expenses for travel to the TNT Doi Inthanon site as well as for local accommodation and subsistence. A set of Instructions for Visiting Astronomers are available to facilitate the logistics of the visit. Visitors are strictly required to fill out an End of Run report and submit it to the NARIT staff within one week after the end of observations.
- PIs are required to read the instructions very carefully before making the applications. PIs must ensure that the applications are filled out truthfully and as accurately as possible. PIs are responsible for the content in the proposal, any misuse of NARIT facilities, data, or false information may result in being disqualified from the application process or any scheduled time slot.
- Target of Opportunity (ToO) applications can be made outside of normal active CfP periods and can be submitted at any time. ToO triggers can also be requested in advance during the regular CfP periods. In this case, the proposal should state clearly how many ToO triggers it is requesting and how much time per trigger (maximum is one hour). Refer to the ToO policy here.
- Titles and Abstracts of all the proposals we received during this and later cycles will be published on the NARIT website.
- Metadata of the data taken during this and later cycles, except the ULTRASPEC GTOs, will be made available on NARIT public scientific data archive. However, the actual data themselves will be kept proprietary for a period of ONE year after the end of the cycle in which the data were taken. After this, the data may be queryable by the public or any user of the NARIT scientific data archive. If for any reason, e.g. nature of the scientific campaign, etc., PI may request an extension of the proprietary period which the TAC will consider on a case by case basis.
Acknowledgment Rules
Any publication resulting from observations and data obtained by the TNT or TRTs MUST include the following sentence:
For the TNT and the TNO-1m:
“Based on observations made with [instrument] at the Thai National Observatory under program ID [ID], which is operated by the National Astronomical Research Institute of Thailand (Public Organization).”
For the TRTs:
“Based on observations made with the Thai Robotic Telescopes under program ID [ID], which is operated by the National Astronomical Research Institute of Thailand (Public Organization).”
