There look to be 2 big name space conferences that are being held in the Pacific Northwest area. These conferences will definitely have a Pacific Northwest feel as will most of the major conferences. Although there are many other space conferences held around the US and around the world, there are few that are held in the Pacific Northwest.
There are a plethora of space conferences hosted by a plethora of organizations over the year. There are options available for attending all, some, or none.
Earth & Space Conference
April 20-23rd, 2020
Held by American Society of Civil Engineers
This is a conference that looks great! A must attend!
Kent WA https://spacefrontier.org/newspace2019/3087-2/
Location: Hyatt Regency, Lake Washington
Date: June 23 – 25, 2020
This great conference has many of the top space talent at the event with great speakers and a ton of networking opportunities. Held in the San Francisco Bay Area last year, the conference looks to maybe be alternating between the Bay Area and Seattle.