In the bedknobs and broomsticks it is called "Star of Astoroth" and is as pictured int he attachement.
The "seal of astaroth" (different spelling) is the center part of the image in the OP. It is one of the seals of solomon from the grimour the keys of solomon.
What is interesting is the seal is intended to cast real magic,much as is the theme of bedknobs and broomsticks.
@freemo Interesting demon BTW. Maybe he should be the patron demon of programmers or STEM: from the interwebs:
"He is a demon of the First Hierarchy who seduces by means of laziness, vanity, and rationalized philosophies. To others, he teacheth mathematical sciences and handicrafts. He doth make men invisible, lead them to hidden treasures, and give them power over serpents. He teacheth secrets. Every question formulated to him sees truthful answer." 😆