0°

0° or 0 degrees may refer to:
 * Longitude: the prime meridian on any planet or moon
 * For most of the 20th century on Earth, the prime meridian (Greenwich)
 * IERS Reference Meridian, the modern reference meridian for time and global navigation on Earth
 * Latitude: the equator
 * freezing point of water (Celsius)
 * absolute zero, the lower limit of the thermodynamic temperature scale (Kelvins)
 * 0 degrees Fahrenheit, approximately -17.78 degrees Celsius