  The nearby Mira-like variable L2 Pup is shown to be undergoing an
unprecedented dimming episode. The stability of the period rules out intrinsic
changes to the star, leaving dust formation along the line of sight as the most
likely explanation. Episodic dust obscuration events are fairly common in
carbon stars but have not been seen in oxygen-rich stars. We also present a
10-micron spectrum, taken with the Japanese IRTS satellite, showing strong
silicate emission which can be fitted with a detached, thin dust shell,
containing silicates and corundum.
