When I was watching the Crew 2 launch this morning, I noticed that while the first stage was coasting up and back down, it kept giving off arc-shaped "puffs". I did not see any corresponding cold gas puffs in the SpaceX livestream I was watching at the time. Does anyone know what these were?

The first stage is the lower, dimmer object in this picture. (The second stage had its engine lit, hence appearing brighter and with a large exhaust plume visible in the sunlight.)

rocket launch seen from great distance

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    $\begingroup$ Note that NASASpaceflight are very good at pushing their videos out to YouTube as fast as possible. They are typically several seconds ahead of the SpaceX feed. So, if you want to compare to the SpaceX feed, you would have to look about 5–10 seconds later. $\endgroup$ Commented Apr 23, 2021 at 20:47

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We watched the launch live from about 60 miles north of the launch site. I also had the live feed on my phone. As the first stage separated, the thrusters fired to change the orientation of the vessel. Allowing for video lag, the puffs we saw live were matched with the seconds-later video.

The video lacks "real life" resolution. We saw numerous arc shaped puffs in the solar illumination that were barely visible in the video. It's also likely that the higher quantity of thruster puffs can be attributed to the limited angle of view of the camera.

As a side note, the timeline from stage separation to the "exit horizon" created a sky full of diffracted sunlight, from the second stage engine as well as remaining artifacts from the thrusters on the first stage. Opinion: This was the most incredible launch we've seen.


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