Observing > Prop Eval & Time Alloc

Proposal Evaluation and Time Allocation

Semester News

Proposals to the NRAO for the scientific use of its telescopes are evaluated on the basis of scientific merit and technical feasibility, and in accordance with NRAO’s policy of non-discrimination and inclusion. NRAO uses a panel-based proposal review system to ensure that scientifically knowledgeable peers representing the broad diversity of the community at large provide expert proposal evaluations. We believe that inclusiveness and broad representation of our users produces the most compelling scientific program.


Proposals to use one, or a combination, of the GBT, the VLA, or the VLBA/HSA are submitted with the Proposal Submission Tool  (PST). Regular, Large, and Triggered proposals must be submitted during the deadlines of 1 Feb and 1 Aug. Director's Discretionary Time (DDT). maybe submitted at any time and are reviewed by NRAO’s scientific staff on the basis of the proposals' scientific merit and technical feasibility. DDT is reserved for Targets of Opportunity and for Exploratory Time. A number of tools are available to support proposal planning; e.g., sensitivity and exposure calculators, and a Proposal Finder Tool (PFT) that may be used to search cover sheets of proposals previously approved for time on NRAO telescopes.

The NRAO has agreements with HST, Chandra, Fermi, and Swift for Joint proposals where telescope time on NRAO’s North American facilities may be granted by these external telescope allocation committees (TACs). Reciprocal agreements exists for HST, Chandra, and Swift where the NRAO TAC may grant time on these external facilities. Since ALMA is an international partnership, it has an independent international proposal review process coordinated by the Joint ALMA Observatory (JAO).