home / medterms medical dictionary a-z list / ethmoid sinus definition Medical Definition of Ethmoid sinus Ethmoid sinus: A collection of air cells within the ethmoid bone, a spongy bone which makes up the front of the floor of the skull and the roof of the nose. From the Greek ethmos, sieve + eidos, resemblance = like a sieve.
Confidence votes 84.8K. It takes 4.05 hours to 4.12 hours for light from the sun to reach Neptune, depending where it is in it's orbit. It takes 4.05 hours to 4.12 hours for light from the sun to reach Neptune, depending where it is in it's orbit.
=== IMPROVED ANSWER: It takes light from the sun to reach earth in 8 minutes and Neptune in four hours, so it is somewhere around there. Since the moon is right next to the earth and Neptune is 30 AU, if you divide four hours (240 minutes) by 30, you get pretty close to 8 minutes. ==== I have a couple of comments.