Here's a timestamped link to Scott Manley's commentary video where he points out that the yellow glow at the bottom of the booster is the heat shielding behind

Here's a timestamped link to Scott Manley's commentary video where he points out that the yellow glow at the bottom of the booster is the heat shielding behind the engines. https://youtu.be/Ysx4t7ICO58?t=550 https://youtu.be/Ysx4t7ICO58?t=550