Stamp celebrating STEM (science, technology, engineering, mathematics).
Feel free to use. Credit me would be nice, but I'm not going to persecute anyone
Didn't use the standard tooth-edged stamp bases, because dammit, this is science and technology! Sticky stamp analogs are so last century.
The "S" is a barred spiral galaxy (specifically, NGC 1365 - image courtesy of NASA.gov)
The "T" is a circuit board (painstakingly crafted from several circuit board images)
The "E" is in a decorative drafting font (Graf Circulum)
The "M" is just a script font letter m, typically used as a symbol for mass in physics equations
Have fun promoting STEM!