Writing proposals

For the Heising-Simons-funded Open Access program, LCO accepts regular (i.e., non-key-project) science proposals from the entire astronomical community. Astronomers at all career stages (faculty, post-docs, students) are eligible to apply. For the 2025A-2028B semesters, the Open Access program provides 80 hours on the 2-m telescopes, 425 hours on the 1-m telescopes, and 80 hours on the 0.4-m telescopes per semester.

In addition to the Open Access program, some scientists are eligible to apply for LCO's own share of network time. The number of hours varies, but in recent (2023-2024) semesters, the time available has been 50 hours on the 2-m telescopes, 500 hours on the 1-m telescopes and 1000 hours on the 0.4-m telescopes. These hours are available to astronomers at institutions with which LCO has formal agreements without guarantees of network time. For 2025A, the eligible institutions are the University of California at Santa Barbara (UCSB)and the Infrared Processing and Analysis Center (IPAC) at Caltech. Members of the extended LCO science team are also eligible to apply.

Proposal submission

Proposals must be submitted through LCO's Observatory portal. Users must first register. After registering, users can click on the "Create or edit proposals" link to access the web-based proposal form. (The form is made available after the call for proposals is issued.) Details of the proposal format are given below.

Proposal format

The fields that must be completed in the proposal submission interface to successfully submit a science proposal are the following:

• Title. Limited to 100 characters
• Abstract. Limited to 500 words
• Principal Investigator. If this is not the author, fill in the PI's last name, first name, email address and institution name.
• Co-investigators. Last names, first names, email addresses and institution names of Co-Is.
• Observing Budget. Requested observing time in hours on each instrument for the duration of the semester. Specify time requested for rapid-response and time-critical observations separately.

The remainder of the proposal must be included in a single pdf file. The file should include the following sections but not an author list:

• Science justification. Background information and a statement of the goals of the project. The results of any previous time allocated for this project should be discussed. Pertinent references should be included. Figures may be embedded.
• Experimental design. A description of the strategy of the observing program, including the characteristics of the targets, the measurements to be made from the data, and what additional work will be done to address the science goals. This section must include an explanation of the observing budget, in which the instrument selection, exposure times, and total number of hours requested are justified. Requests for Rapid Response or Time Critical observations must be justified independently. If unusual scheduling constraints might impact the project's success, identify them.
• Related programs on other telescopes. A concise account of other programs which relate to this proposal.

Citations to publications should be numbered in sequential order in the proposal text. Later citations to the same publication should repeat the original number.

Beginning on a new page from the justification and design sections (above), the file should include the following sections:

• List of references in (number) order in which they were cited in the justification and design sections.
• Report on past use of LCO time. A concise account of time used on LCO network in the past 3 years.
• Applicant's related publications. Up to 15 relevant publications from the past 3 years.

The proposal body must conform to the following constraints:

• The font size must be 11 points or larger. (Caption fonts may be smaller.)
• Margins on all edges must be at least 1 inch.
• Line spacing must be no denser than 6 lines per inch.
• The file size must be under 10MB.
• The recommended length is 7 pages.

Available telescopes, instruments, software tools:

For the 2025A semester, Las Cumbres Observatory has two 2-meter telescopes, thirteen 1-meter telescopes and ten 0.4-meter telescopes available for science observations. The 2-m telescopes are equipped with MuSCAT 4-band multi-channel imagers and FLOYDS low-dispersion spectrographs. The 1-m telescopes are equipped with Sinistro imagers.  The Network of Robotic Echelle Spectrographs (NRES) has units installed on 1-m telescopes at our Cerro Tololo (Chile), McDonald (Texas), Sutherland (South Africa), and Wise (Israel) sites. The 0.4-m telescopes are Planewave DeltaRho350 telescopes with QHY600 cameras.

For information on all Network instruments, please consult the Observatory Instruments page.

The Exposure Time Calculator (ETC) can help you estimate your observing time budget. The ETC will calculate the exposure time required to achieve a given signal-to-noise ratio for an object of a given magnitude. You refine the calculation by selecting the telescope class (2-m, 1-m, or 0.4-m), filter (U, B, V, etc.), lunar phase, and airmass.

The Target Visibility Calculator shows how observable a given position (RA & Dec) are on the LCOGT network. A target's "seasonal visibility" is the UT range that the target is visible over a range a dates. A target's "daily visibility" is its trajectory of altitudes/airmasses as seen at the network sites on a particular (user-selected) day.

Observation overheads

Every observation has a time overhead associated with it. For every new object acquired, there are associated Slew & Settle times and Acquisition & Setup times.  For every exposure, there is an associated readout time. And for every FLOYDS spectrum, there are associated calibration (reference arc and flat) observations.  Calibration observations (biases, darks, flats) for the imagers are obtained during twilight, and  the time for these is not charged to users.  

When calculating the observing budget for your proposal, you should takes these times into account:

Example 1: An observation request that consists of three 60s exposures through the V filter with Sinistro. Total request = 90s (slew and settle) + 18s (acquisition and setup) + [3 x (60s + 28s) (exposure plus readout)] = 372 seconds.

Example 2: A 15-minute integration with FLOYDS. Total request = 120s (slew and settle) + 150s (acquisition and setup) + 900s (exposure) + 26s (readout) + 95s (calibration) = 1291 seconds.

Time-charging Policy

Time charged includes all the overhead associated with slewing the telescope, acquiring the target, preparing the instrument, and reading out the detector, in addition to the actual exposure time.  You should include overheads in the time request in your proposal. Use the appropriate Slew & Settle time and Acquisition & Setup time for each new object, then add the readout time for each separate exposure.

Time is charged for all exposures attempted, regardless of the quality or delivery of the data.

The Observatory portal displays the number of hours of an approved allocation that have been used.

Observing Modes

LCO supports three observing modes:

• Queue-scheduled observations are sequences of one or more "blocks" defined by a single time window (for one) or a cadence (for more than one). A block is a set of exposures, intended to be executed contiguously. A block may be several identical exposures or it may involve filter changes or exposure time changes.
• Time-critical observations must be made at relatively tightly constrained times that rarely occur. Examples are predictable (but infrequent) transits, observations simultaneous with other observatories, and follow-up to rare events that evolve quickly. These observations are submitted to the scheduler with high priority, so that they have a good chance of getting scheduled at the critical time.
• Rapid-response observations are intended to take place as quickly as possible (typically within 10 minutes of the target's availability). Execution of a rapid-response observation will terminate an ongoing queue-scheduled block. If a rapid-response observation cannot be executed immediately, it will be executed as soon as possible, up to a limit of 6 hours.

Proposals must request queue-scheduled, time-critical and rapid-response time observations separately, and time-critical and rapid-response requests must be adequately justified.

Authors of proposals that have special scheduling constraints (e.g., simultaneous observations by two telescopes, multi-night or multi-site time series) are strongly advised to contact LCO personnel for advice on feasibility before submission.

Proposal Evaluation and Priority

All proposals will be reviewed by a Time Allocation Committee, whose members are selected from the astronomical community and are not affiliated with LCO. Proposals will be evaluated based on scientific merit and technical feasibility. We welcome proposals that have a significant educational component. For proposals that are accepted, our goal is to execute all observation requests.  Only observations that can be executed during the semester may be requested. TAC priority will be used to guide choices, all other things being equal.

Data Access

Pipeline reduced data may be searched and downloaded through the LCO Science Archive.  Data are available in the archive soon after they are transferred from the observing site (typically <10 minutes after the instrument shutter closes).

Science data has a default proprietary period of 12 months from the time of a given observation.  Data that has reached the end of its proprietary period is accessible from the LCO Science Archive.