International Date Line International Date Line The International Date Line (IDL) is an imaginary line of demarcation on the surface of Earth that runs from the North Pole to the South Pole and demarcates the change of one calendar day to the next. It passes through the middle of the Pacific Ocean, roughly following the 180° line of longitude but deviating to pass around some territories and island groups. The IDL is roughly based on the meridian of 180° longitude, roughly down the middle of the Pacific Ocean, and halfway around the world from the Greenwich meridian. In many places, the IDL follows
Racah (crater) Racah (crater) Racah is a lunar impact crater on the far side of the moon. It lies almost due south of the larger crater Daedalus, and lies across lunar longitude 180°W, i.e. the longitude that is diametrically opposite to the Earth. To the west-southwest of Racah is the crater Aitken, and to the southeast lies De Vries. The rim of this crater is eroded and is not quite circular, having a prominent outward bulge along the west-northwest side. The edge is somewhat damaged along the southern rim, but no significant craters lie along the side. The interior floor is uneven