How Pc logo draws the earth around the sun (animation)

To xQ :c :r

setpc :c pd (stampoval :r :r "true)

end

To yd :j

Pdxq 9 20 rt: j pu FD 50 rt 90 pdxq 810 wait15xq1510lt 90bk50lt: jxq1520.

pu rt 2.5 fd 200*0.0872 rt 2.5

yd :j+ 15

end

To ryx, sun, moon and stars

Draw pd xq 12 50 pu fd 200 rt 90 yd 0.

end

cs ryx