This looks like a stray light from the lens. This happens when the light source is close to the angle of view of your lens.
Stray light refers to a phenomenon in which light is scattered or flared
in a lens system, often in response to bright light, producing a
sometimes unwanted artifact in the image. This is happening through
light diffused by the imaging mechanism itself, for example by
internal reflection and diffusion of the material imperfections of the
lens. Goals with a lot of things like zooms tend to
present greater stray light because they contain a relatively large number
interfaces that can be internally distributed. These mechanisms
differs from the mechanism of generation of focused images, which depends on the
rays of the refraction of the light of the subject himself.
The rocket manifests itself in two ways: as visible artifacts and as
haze on the image. The mist gives the image "faded" by
reduced contrast and color saturation (adding light to a dark image)
regions, and adding white to saturated regions, reducing their
saturation). Visible artifacts, usually in the form of the lens iris,
are formed when the light follows a path through the lens that contains
one or more reflections of the surfaces of the lens.