by Davis Murphy last modified Dec 08, 2016 by Jonathan Romney

The LBO operates the Very Long Baseline Array (VLBA) for use by the scientific community. The following guides scientific users through the process of proposing for and using LBO observing time.


For all questions related to observing with the VLBA please use the HelpDesk.

Calls for Proposals

Each Call for Proposals invites scientists to propose for observing time on the VLBA. The LBO issues two Calls per year for proposal submission deadlines on February 1 and August 1. Each Call summarizes relevant policies and procedures, and provides important information about telescope and instrument performance. Current Call for Proposals.

Proposal Preparation

The Proposal Submission Tool used by scientists to prepare and submit their observing time requests is available via NRAO Interactive Services. Proposers should consult relevant technical documentation about the capabilities of the telescope(s) and instrument(s) requested for their proposals. The LBO staff can be consulted via the Help Desk.

Proposal Evaluation &  Time Allocation

An Observatory-wide panel-based system that depends on community members for scientific review is used to evaluate proposals.

Observing Preparation

Successful proposers provide the observing details required to schedule the VLBA and acquire scientific data. The observation prep software used is Sched.


All operational NRAO telescopes employ dynamic scheduling to ensure that observing projects benefit from the best possible conditions. The NRAO staff manage the logistics of dynamic scheduling.

Data Processing

Scientists using the VLBA employ a variety of software and analysis packages to reduce and analyze their data, depending on their specific needs, experience, and skills.

Publication Support

When requested, page charges are available for authors at U.S. scientific or educational institutions when the paper reports original observations acquired with the VLBA, the paper contains original analyses of archival data and/or is based on a significant amount of previously unpublished archival data. In some cases, support may be available for page charges for papers containing original instrumental or theoretical analyses with direct implications for the VLBA.

News Releases 

If you discover something potentially newsworthy using the VLBA, our Education and Public Outreach team would welcome the opportunity to work with you to bring public recognition to your result.

Data Archives

Raw data and calibrations for all observing projects are made publicly available through the NRAO Data Archives after a proprietary period of 12 months following a project's last observation.