TL;DR: NASA's Infrared Telescope Facility will accept Semester 2027A proposals from 1 September through 1 October 2026, with the window closing at 5:00 p.m. Hawaii Standard Time.

The newest verified development is the formal opening of that observing competition for the 3.2-meter infrared telescope on Mauna Kea. According to NASA Science in its posting titled NASA IRTF Semester 2027A Call for Proposals, the opportunity runs 1 September to 1 October 2026. According to the American Astronomical Society in its notice titled Call for Proposals: NASA Infrared Telescope Facility – Semester 2027A, submissions remain open until 1 October at 5:00 p.m. Hawaii Standard Time, listed as 11:00 p.m. EDT.

For astronomers in the United States who study planets, small bodies, stars, and distant objects at infrared wavelengths, the announcement sets the schedule for requesting time in the first half of 2027. The facility supports imaging, spectroscopy, rapid-response observations, and remote participation, with preparation materials centered on its proposal-information page.

Proposal window and deadline

The Semester 2027A competition has a defined one-month submission period.

NASA Science describes the call as open 1 September to 1 October 2026. The American Astronomical Society gives the closing moment as 1 October at 5:00 p.m. Hawaii Standard Time, equivalent to 11:00 p.m. EDT. That dual time-zone listing matters for mainland applicants, because a proposal finished late in the evening Eastern time must still meet the Hawaii-based cutoff.

The author credit on the society notice identifies Warren Skidmore of the NASA Infrared Telescope Facility at the University of Hawaii. The NASA Science page credits the Physics of the Cosmos Team and Patricia Tyler and carries a date of 19 August 2026, while the society posting carries a date of 18 August 2026. Those dates place the announcement immediately before the September opening, giving teams about six weeks from initial notice to prepare and about one month while the call is formally open.

The practical step for interested teams is to treat 1 October as a hard stop in Hawaii time. Eastern, Central, Mountain, and Pacific observers all face the same Hawaii-clock deadline, so calendar reminders should use 5:00 p.m. Hawaii Standard Time rather than local midnight.

Where to find instruments and preparation tools

Both announcements direct proposers to the facility's central proposal resource for technical planning.

NASA Science points applicants to full details on the instruments, exposure time calculators, and all other information needed for proposal preparation. The listed address is the IRTF observing call-for-proposals page at the University of Hawaii Institute for Astronomy. The American Astronomical Society likewise refers readers to the webpage for proposing time on IRTF, including instrument details, exposure-time calculators, and other proposal-preparation information.

That resource is therefore the authoritative place to check available modes, sensitivity estimates, overheads, and formatting rules. Applicants seeking time for Semester 2027A should start with the exposure-time tools and instrument descriptions there, then shape science goals, target lists, and time requests around what those pages document.

Access, however, was disrupted around the announcement. NASA Science states that the URL in the message may not work right now because power was lost across most University of Hawaii and Maunakea facilities due to Hurricane Lala. The American Astronomical Society carries a similar notice that, at the time of publishing, links were temporarily not working because of the impacts of Hurricane Lala, and it asks readers to check back later. Teams should therefore plan for possible intermittent access and revisit the proposal page rather than treating an early failed connection as a permanent problem.

What IRTF offers in imaging and spectroscopy

The core technical case for IRTF is broad infrared coverage in both imaging and spectroscopy.

Both NASA Science and the American Astronomical Society describe imaging capabilities using broad- and narrow-band filters. Both describe spectroscopic observing capabilities covering wavelengths from 0.5µm to 20µm, with resolutions of 50 to 80,000. That span reaches from visible-adjacent light through near-infrared and into mid-infrared wavelengths, allowing one observatory to address reflected sunlight, thermal emission, molecular bands, and dust-related features depending on the selected mode.

The resolution interval is also wide. Low-resolution settings near 50 can record broad spectral shapes efficiently, while settings up to 80,000 can separate narrow lines. NASA Science presents that 0.5µm-to-20µm coverage and 50-to-80,000 resolution range as part of a unique range of capabilities. The American Astronomical Society uses the same wavelength and resolution figures, reinforcing that applicants can request very different types of data without leaving the facility.

For proposal writing, the implication is direct: teams should justify the chosen filter set, wavelength interval, and resolution as part of the science case. A program seeking faint continuum or broad solid-state structure will look different from a program seeking closely spaced gas lines, even though both fall inside the advertised IRTF envelope.

Solar-system tracking and rapid-response science

Moving-target performance is highlighted as a distinctive part of the call.

Both announcements state that non-sidereal tracking of solar system objects, including near-Earth objects, is a particular strength. Non-sidereal tracking means the telescope can follow a body moving relative to the stars, rather than holding fixed on stellar coordinates. That ability supports asteroids, comets, outer-planet satellites, and other objects whose apparent motion would otherwise trail or leave the slit and imaging field.

Target of Opportunity interrupt and time-critical programs are supported. NASA Science adds that the facility is especially interested in receiving proposals that require regular followup observations after a ToO program is triggered. The American Astronomical Society describes support for target-of-opportunity interrupt and time-critical programs without adding a separate follow-up sentence, but both notices place rapid-response work inside the Semester 2027A scope.

The distinction matters for planning. An interrupt request can pause scheduled work for a sudden event, while time-critical work must occur at a fixed epoch such as a close approach, occultation, apparition window, or spacecraft encounter geometry. The added NASA Science language about regular followup after a ToO trigger signals interest in monitoring campaigns, not only single-epoch snapshots. Proposers with newly discovered comets, outbursting objects, approaching near-Earth objects, or mission-support timelines can therefore frame both the trigger and the requested cadence.

Remote observing and training for new users

The call describes observing as normally remote, with pathways for newcomers and difficult programs.

Both NASA Science and the American Astronomical Society state that observing is usually conducted fully remotely. Both state that in-person observing to build experience or conduct particularly challenging programs is available. Both add that accommodation is included and that transportation between the observatory and accommodation may also be provided. NASA Science phrases the training point as pre-observing training offered for new observers and those unfamiliar with the instruments. The American Astronomical Society phrases it as pre-observing training offered for new observers and those unfamiliar with the instruments in closely matching terms.

That structure lowers the barrier for first-time infrared observers while preserving summit access where hands-on presence helps. A graduate student, a team using an unfamiliar spectroscopic mode, or investigators attempting demanding acquisition or calibration can seek instruction before the run and, where justified, request to be present. Experienced teams comfortable with remote operations can plan to observe without travel, which can simplify scheduling, staffing, and costs for multi-night or widely spaced monitoring.

Proposers should state their observing approach in the submission. A remote plan should show that the team can operate the requested mode from a distance. A request for on-site presence should explain why experience-building or program complexity makes travel appropriate and how accommodation and summit logistics fit the schedule documented through the official proposal materials.

A Mauna Kea site built for infrared work

The telescope's location and design are presented as central to its infrared role.

NASA Science describes the NASA IRTF as a specialized, high-performance infrared observatory. It identifies the instrument as a 3.2-meter telescope in Hawaii optimized for infrared observations, supporting planetary science, NASA missions, and broader astronomical research. The same NASA Science material places the facility at the summit of Mauna Kea, Hawaii, at an altitude of approximately 13,600 feet.

The site characteristics listed are high transmission, excellent seeing, minimal water vapor, and low thermal background ideal for infrared astronomy. Each element connects to infrared performance: dry, high-altitude air reduces atmospheric water absorption; stable seeing sharpens images; and a low thermal background helps mid-infrared measurements where heat from sky, telescope, and surroundings can otherwise dominate faint astronomical signals.

That combination explains why the call covers both solar-system and broader astronomical research. The telescope is not framed as a general optical instrument with added infrared modes. It is framed as an infrared-optimized national capability placed where atmospheric conditions favor the measurements proposers are being invited to request.

Record of support for NASA and international missions

The announcement places Semester 2027A in the context of long mission-support service.

NASA Science states that IRTF has provided ground-based support for numerous NASA and international missions. The listed missions include Cassini/Huygens, Deep Impact, Stardust, Mars Reconnaissance Orbiter, MESSENGER, DAWN, Lunar Reconnaissance Orbiter/LCROSS, Juno, New Horizons, Hayabusa, Rosetta, and Mars Express.

That history spans outer planets, comets, asteroids, the Moon, Mars, Mercury, and small-body sample-return targets. It signals to 2027A proposers that mission-support observations remain within scope, alongside independent planetary science and wider astronomical research. Teams working on active NASA flight projects, archived mission targets, international mission counterparts, or future mission reconnaissance can cite that ground-based role when explaining why IRTF time is the appropriate complement to spacecraft data.

The list also helps reviewers locate precedent. A proposal tied to a giant-planet atmosphere previously studied by a flyby or orbiter, a comet previously encountered by an impactor or sample collector, or a dwarf planet or Kuiper Belt object previously visited by a distant flyby can point to the facility's prior participation in that class of coordinated observation.

What to do before 1 October

The immediate action is technical preparation followed by timely submission.

First, monitor the official IRTF call-for-proposals page referenced by NASA Science and the American Astronomical Society for instrument details and exposure-time calculators. Because both sources warn of temporary Hurricane Lala-related outages affecting University of Hawaii and Maunakea links, applicants should retry the page and avoid waiting until the final day.

Second, define wavelength coverage, resolution, filters, tracking needs, and time-critical constraints explicitly. The advertised 0.5µm-to-20µm range, 50-to-80,000 resolution range, broad- and narrow-band imaging, and non-sidereal tracking for solar-system bodies including near-Earth objects provide the factual framework. A complete request will map each target to one of those capabilities rather than leaving the technical match implicit.

Third, address operations and experience. New observers and teams unfamiliar with the instruments can note expected pre-observing training. Teams seeking regular followup after a Target of Opportunity trigger should describe the trigger, response cadence, and total time needed, reflecting the follow-up interest stated by NASA Science. Teams needing summit presence for experience or especially challenging work should justify in-person observing and account for the accommodation and possible transportation arrangement described in both notices.

Submitted by 1 October at 5:00 p.m. Hawaii Standard Time, a well-documented proposal can compete for remote or, where warranted, on-site time on a 3.2-meter Mauna Kea telescope whose infrared mission extends from near-Earth objects to NASA mission targets and beyond.

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