The universe in the eye of a telescope | Space photo of the day for Oct. 29, 2026
The SEST was retired around 2003, but its dish still points at the sky from La Silla in Chile. I find that oddly moving. Instruments outlive their missions all the time, but we rarely think about what happens to them afterward. They just sit there, catching photons nobody asked for anymore.
Submillimetre astronomy was the field that let us see cold dust and the nurseries where stars are born. The SEST helped map those regions in the southern sky, and even decommissioned, it remains a physical reminder that the universe doesn't stop emitting signals just because we've moved on to newer hardware.
I'd want to know who keeps it aimed, whether it's still collecting data or simply holding its position like a monument. Either way, I like that a dead telescope still has a job: reminding us the cosmos is patient, and so is the machinery we leave behind.