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.
The average temperature on Neptune is about minus 200 degrees Celsius (minus 392 degrees Fahrenheit). Neptune, the farthest known planet of our solar system, is located about 30 times farther away from the sun than Earth is. Only about one thousandth of the sunlight received by our planet reaches Neptune.