Short stop in vienna

I'm flying from Bangkok to Helsinki, arriving Vienna Airport at 05.35am and depart 10.30am.
Anyone have a good suggestion for me? first, i think i gonna go to Schonbrunn Palace, but it's too early.
And in this case, What time i'll have to return to the airport?

Thanks, everyone.

Are you saying that you are in Austria for only 5 hours? Not much time to do anything imo!

I think most museums and sights open around 9 or 10 am. Too late for you.

I would recommend to get right to the center, to check out St. Stephens Cathedral (which opens at 6 am during the week, 7 am on Sundays), stroll around a bit, it's a really nice area and have some expensive coffee.

If you have your luggage checked through to Helsinki it should be enough to be back at the airport around an hour, 45 minutes in advance.

These are the transportation options.
They run only every 30 min, and take about 20 min, so make sure to plan your return well.

Probably you'll make it to the center at 6:30, and you'll have to leave around 9:00. Indeed not much, but for me still better than hanging around at the airport.