Early Evening in Juneau

[cft8]

We're in Juneau on a Sunday on the Ovation of the Seas. Our excursion (Whale Watching & Mendenhall) leaves as soon as we arrive in port, and returns at 5:45, but all aboard is not until 8:30. Will there be anything significant open later in the day (I'm thinking more of museums or historic sites than shopping or eating)? If not, I'm thinking of just trying to book a spot on the NorthStar for when we get back on board. I see that the Mt. Roberts Tramway stays open until 9, but if we can get the NorthStar, we can get a decent view for free!