We are pleased to announce that the OPTICON 2026A call for proposals is now open, with observing time available on the participating facilities.Applications for telescope time should be submitted using the proposal template attached below. Applicants are asked to download and complete the document, and return the completed form as a PDF by email to: OpticonAlliance@ia.forth.gr. As the number of participating facilities in this call is limited, applicants are also encouraged to check the relevant telescope or observatory website in case any facility requires specific additional information. Applicants may request observing time on multiple facilities through a single proposal. Late applications will not be considered. Please note that, for this call, applications are invited from the international community excluding USA-based observers. It is expected that future calls will broaden eligibility to include USA-based observers. Applicants submitting a proposal will be expected to provide feedback on at least one anonymised proposal as part of the review process.OPTICON_Application_for Telescope_Time_2026A.docxNote: TBL and Aristarchos facilities will be available for future calls, but are currently in the process of being upgraded. Please also consider the BHTOM network of telescopes for time-domain observations.The call for proposals will close on April 17th 2026 at UT 23:59. THE FACILITIES OFFERING OBSERVING TIME ARE SHOWN BELOW: The Baldone Schmidt telescopeObservatory Location: LatviaObservatory Webpage link: https://www.baldonesobservatorija.lu.lvTelescope size: 1.2 mTelescope Description: Schmidt telescopeInstrumentation: Baldone Schmidt + device, U, B, V, R, I photometry or without filter, and 4 degree objective prism.Scientific usage: Photometry and SpectroscopyTime allocation information: March 3 nights: U, B, V, R, I photometry or without filter; March 2 nights: 4 degree objective prism; April 3 nights: U, B, V, R, I photometry or without filter; April 2 nights: 4 degree objective prism; May 3 nights: U, B, V, R, I photometry or without filter; May 2 nights: 4 degree objective prism; August 2 nights: U, B, V, R, I photometry or without filter; August 2 nights: 4 degree objective prism; September 2 nights: U, B, V, R, I photometry or without filter and 4 degree objective prism.Lead contact: Ilgmars EglitisLead contact email: ilgmars.eglitis@lu.lvNotes: The telescope cannot be controlled remotely. Observations are provided by an operator according to the order description and is a co-author of subsequent publications. Due to the uncertain weather conditions in the Baltics, it is recommended to plan at least a one-week period for observations. Byurakan Astrophysical Observatory (BAO)Observatory Location: ArmeniaObservatory Webpage link: https://www.bao.am/telescopes/2.6m/Telescope size: 2.6 mTelescope Description: Classic Cassegrain reflector, also with use of the primary focus f/3.85 and 2 Nasmyth foci.Instrumentation: SCORPIO - Spectral Camera with Optical Reducer for Photometric observationsScientific usage: Photometry and SpectroscopyTime allocation information: 30 nights (per year)Lead contact: Areg MickaelianLead contact email: aregmick@yahoo.com Joan Oró Telescope (TJO)Observatory Location: Montsec Observatory (OdM-IEEC), CataloniaObservatory Webpage link: https://montsec.ieec.cat/en/astronomy/tjo/Telescope size: 0.8 mTelescope Description: Robotic 0.8 m Ritchey-ChrétienInstrumentation: MEIA2 (Imaging camera) and ARES (medium resolution spectrograph)Scientific usage: Photometry and SpectroscopyTime allocation information: 20 hoursLead contact: -Lead contact email: obsmontsec@ieec.catNotes: Proposals can also be submitted until 15 May 2026 (Fri) (at 21:59 UT) under the same conditions as the regular call (open time). Kottamia Astronomical Observatory (KAO)Observatory Location: EgyptObservatory Webpage link: https://www.nriag.sci.eg/overview-at-kottamia-astronomical-observatory/Telescope size: 1.88 mTelescope Description: CassegrainInstrumentation: KFISP, Kottamia Faint Imaging Spectro-PolarimeterScientific usage: Photometry, Spectroscopy and spectro-polarimetryTime allocation information: 45 nights until end of 2026Lead contact: Gamal Edin HamedLead contact email: gamal.hamed@nriag.sci.eg Las Cumbres Observatory (LCO)Observatory Location: VariousObservatory Webpage link: https://lco.globalTelescope size: 13x1 m, 10x0.35 mTelescope Description: Robotic telescopesInstrumentation: All of the 1 m telescopes (except the Wise Observatory) have Sinistro imaging cameras. Four of the 1 m sites (CTIO, SAAO, McDonald Observatory, and Wise Observatory) also have high resolution NRES spectrographs. 0.4 m have QHY600 CMOS camera systems.Scientific usage: PhotometryTime allocation information: ~100 hours/semester for 1 m or ~200 hours/semester for 0.35 m. The 2 m telescopes are not available for this call.Lead contact: Martin DominikLead contact email: md35@st-andrews.ac.ukNotes: Our semesters run from 1 Feb to 31 Jul, and from 1 Aug to 31 Jan each year. Liverpool Telescope (LT)Observatory Location: Canary islands, La Palma, SpainObservatory Webpage link: https://telescope.livjm.ac.ukTelescope size: 2 mTelescope Description: 2.0 m unstaffed fully robotic telescopeInstrumentation: Currently mounted/operational instruments: IO:O, RISE, LIRIC, SPRAT and MOPTOP https://telescope.livjm.ac.uk/TelInst/Inst/index.phpScientific usage: Photometry and SpectroscopyTime allocation information: 50 hours (July 1st semester start)Lead contact: Christopher CopperwheatLead contact email: C.M.Copperwheat@ljmu.ac.ukNotes: For any ToO type proposals, feedback from the TAC on proposals considered particularly high priority. Proposals only to be accepted if they are not eligible to be submitted to one of the other time allocation routes (non-UK or Spanish PIs) Moletai Astronomical ObservatoryObservatory Location: Vilnius University, LithuaniaObservatory Webpage link: https://mao.tfai.vu.lt/sci/en/news/Telescope size: 51 cmTelescope Description: 35/51 cm Maksutov-type telescope. Can be operated remotely.Instrumentation: CCD photometer and a set of BVRI and Vilnius photometric system filters.Scientific usage: PhotometryTime allocation information: 10 nights per month on averageLead contact: Erika PakstieneLead contact email: erika.pakstiene@tfai.vu.ltNotes: Service observations are available for the collaborative projects. Rapid Eye Mount telescope (REM)Observatory Location: La Silla, ChileObservatory Webpage link: https://www.eso.org/public/teles-instr/lasilla/rem/ & http://www.rem.inaf.itTelescope size: 0.6 mTelescope Description: Rapid-reaction automatic telescopeInstrumentation: REMIR, an infrared imaging camera, and ROS2, a visibile imagerScientific usage: PhotometryTime allocation information: 112 hours/semesterLead contact: Emilio Carlo MolinariLead contact email: emilio.molinari@inaf.it Skalnaté Pleso ObservatoryObservatory Location: Vysoké Tatry, SlovakiaObservatory Webpage link: n/aTelescope size: 1.3 m, 61 cmTelescope Description: No current dedicated webpage with details of telescopes and instruments. Information on the Echelle spectrograph: https://www.astro.sk/en/research/departments/stellar-department/Instrumentation: 1.3 m Nasmyth Cassegrain (echelle spectroscopy, imaging/photometry). 61cm telescope (imaging/photometry)Scientific usage: Photometry and SpectroscopyTime allocation information: 14 nights per semester/per telescopeLead contact: Theodor PribullaLead contact email: pribulla@ta3.skNotes: Observing time not allocated in formal semesters. Service observations are preferred, but for observing runs longer than 2 or 3 nights, we are open to a hybrid regime in which our technician operates the telescope and the observer takes control of exposures. Telescopio Nazionale Galileo (TNG)Observatory Location: Roque de los Muchachos Observatory, La Palma, SpainObservatory Webpage link: https://www.tng.iac.esTelescope size: 3.6 mTelescope Description: Alt-azimuth telescope with a Ritchey-Chretien optical configuration and a flat tertiary mirror feeding two opposite Nasmyth fociInstrumentation: SiFAP2, GIANO-B, HARPS-N, NICS, DOLORESScientific usage: Photometry and Spectroscopy (Imaging polarimetry and spectropolarimetry are not currently available).Time allocation information: 5 nights per semester for the next 2 semesters (total of 10 nights between october 26 to september 27)Lead contact: Adriano GhedinaLead contact email: ghedina@tng.iac.esNotes: Observations should be done in Vistor mode except for Exo-planetary proposals which if needed could take advantage of Time-sharing. Visitors should provide their own funds for travelling. For specific practical information about individual telescopes or instruments, applicants are asked to contact the relevant local observatory team directly.For general queries regarding this call, please contact:Gerry Gilmore: gilmore@ia.forth.gr Fraser Gillan: andrew.gillan@ncbj.gov.plGudrun Tausch-Pebody: gp383@cam.ac.uk