Power Loss/Speed Studio XL turns itself off

I had a short power outage… My Studio XL was connected to a powerstrip.

I rebooted my computer, and tried turning on the drive. It makes the usual beep. All lights go blue.
And then it turns itself off (before mounting, etc.)

Any ideas of what’s going on?

Thanks!

Answering my own question:

I unplugged everything. Came back in the AM, reconnected the TB cable, plugged in the power cable and it returned.
Really disconcerting none the less.