Stock futures are pointing to a mixed open for major indexes after the Dow closed at another record high yesterday; SpaceX has reached the expiration of its first lock-up period, putting many more shares on the market; shares of Western Digital and Sandisk are tumbling following the release of quarterly results from the memory chip makers; Honeywell Aerospace shares are sinking after a lackluster earnings report; and Moderna shares are gaining on the news of FDA approval for its mRNA-based flu shot. Here's what you need to know today.