On their website long in advance or on the day you want to attend (be on the website at 6am to grab tickets, they go fast)
Website or try your luck with walk-in
Go onto the web site at about 6:30 am the day you want to go. Keep clicking and checking. I did this for about 5 minutes and finally a time slot came up.
I went on yesterday, I was on the website by 7am and they emailed me the tickets...
https://nmaahc.si.edu/visit/passes Go to the above link to request your passes. You'll have access to them immediately on your cell.. no need to o print them
You can go to the web site
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