(planned balloon-borne 2-m telescope and spectrometer)
TIM (Terahertz Intensity Mapper)
is a planned balloon-borne 2-meter telescope and
imaging spectrometer aimed at intensity mapping[CII] and [NII].
It is the follow-up of a NASA-funded study called
STARFIRE (for
Spectroscopic Terahertz Airborne Receiver for Far-infrared Exploration).
It underwent an engineering test flight in New Mexico in September 2024,
and plans are for an operational flight in 2026 or possibly 2027,
I believe from Antarctica.