Blue Origin has hot fired its BE-4 rocket engine for the first time
A few frames of the video caught my eye: <a href="https://screenshots.firefox.com/eOm06NUSg0CSkb1a/arstechnica.com" rel="nofollow">https://screenshots.firefox.com/eOm06NUSg0CSkb1a/arstechnica...</a><p>It looks like there's some sort of harmonic wave in the blast. Does anyone have any insights on why the design would result in that?