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.
How long does it take light to travel from Sun to Pluto in seconds? Pluto's orbit is highly eccentric. When Pluto is at its minimum distance form the Sun, sunlight takes about 14800 seconds to reach it (just over 4 hours). At its maximu â¦ m, the light takes about 24600 seconds (nearly 7 hours).