Spreading your wings

The Smithsonian Submillimeter Array (SMA) appears to have deployed its dishes to their maximum extent. A few weeks ago I posted a picture in "Odd one out" where you can see them about as closely grouped as they can get, with the "sergeant major" to the left (see picture below). Now they're as far apart as I think they can get, obviously trying to maximise their delivered resolution at the expensive of sensitivity. I wonder what they're observing?

At this time of year the Galactic plane is roughly overhead at around midnight, so at sunset it'll be very low on the eastern horizon which is where the dishes are pointing. Maybe they're studying our Galactic centre? It's one of the hottest topics in Galactic astronomy these days.