Array Configuration Schedule

The SMA configuration schedule is driven primarily by a few factors:

• the relative numbers of requests for different configurations in approved observing proposals, including Large Scale and Key Projects
• the right ascension distribution of approved observing targets in different configurations, including Large Scale and Key Projects
• the availability of antennas, subject to maintenace and increasingly upgrades (such as new cryo systems and site infrastructure) continuing into 2025

The array configuration flow for 2024B is:

Compact --> Subcompact --> Compact --> Extended --> Very Extended* --> Compact

The timeline for 2024B, subject to change, is:

Semester 2024B Configuration Schedule
configuration	start	end
compact	16 Nov 2024	14 Jan 2025
subcompact	16 Jan 2025	28 Jan 2025
compact	30 Jan 2025	18 Mar 2025
extended	20 Mar 2025	15 Apr 2025
very extended*	17 Apr 2025	>29 Apr 2025
compact	17 Apr 2025	end of semester

*NOTE: SMA infrastructure supporting the very extended array suffered significant storm damage in August 2024 (including road washouts and exposed utility and communication lines), affecting the two pads on the western arm of the very extended configuration. While very extended had been scheduled for April, the damage has not been repaired and we must sadly skip very extended in 2025A.

Reconfiguration of the array typically requires 2 to 3 days, including antenna moves and recalibration. Schedule is subject to change.