It looks like we may never know if Happy Feet the wayward penguin makes it home.
"The satellite transmitter that was attached to Happy Feet has not been received since Friday 9 September 2011, NZ time," report the analysts at Sirtrack, which had been following the little guy's progress.
"This leads to the conclusion that either the satellite transmitter has detached or an unknown event has prevented Happy Feet from resurfacing," they add.
"Unknown event," of course, could mean the worst for Happy Feet.
Happy Feet, you may recall, showed up on a beach in New Zealand earlier this year — thousands of miles from his home in Antarctica. He was weak and needed care from the Wellington Zoo, which over the course of two months nursed him back to health.
A little more than a week ago, after being given a lift part way, he was released into the ocean and started to swim south.
Sirtrack is still going to watch for the tracking device's signal. There's an online map here.