oh! I need this too! Anybody?

Took a quick look and this will remove the spaceship from session pages:

.lrn-widget-course-session-blankSlate .ui-illustration {
display: none;
}

Note: This is related to the new course layout which is still undergoing development and could change.

.lrn-widget-course-session-blankSlate .ui-illustration {
display: none;
}

THANK YOU! Exactly what I needed! 

Does anyone have the CSS code to replace the spaceship image when a session is not available for a course? I have changed the text, but now need to replace the image.
 

/*Replace spaceship with custom image */

.lrn-widget-course-session-blankSlate .ui-illustration

{

    background: url(THE-URL-TO-IMAGE-GOES-HERE) no-repeat center;

    background-size: contain;

}

.lrn-widget-course-session-blankSlate .ui-illustration svg {

    visibility: hidden;

}

Thank you for the response. I must be doing something wrong because it is still there. Anything else I can try?

/*Replace spaceship with custom image */

.lrn-widget-course-session-blankSlate .ui-illustration

{

    background: url(https://cdn5.dcbstatic.com/files/a/s/astec_university_docebosaas_com/userfiles/13046/writing_pencil.png) no-repeat center;

    background-size: contain;

}

.lrn-widget-course-session-blankSlate .ui-illustration svg {

    visibility: hidden;

}

/*Replace spaceship with custom image */

This works for me now:

.ui-illustration.ui-illustration-size-md

{

    background: url("https://cdn.iconscout.com/icon/free/png-512/free-twitter-x-icon-download-in-svg-png-gif-file-formats--logo-social-media-logos-pack-icons-7740647.png?f=webp&w=256") no-repeat center !important;;

    background-size: contain;

}

.ui-illustration.ui-illustration-size-md svg {

    visibility: hidden !important;

}