Circle of latitude can be calculated by a common sine or cosine function. The 60th parallel north or south is half as long as the Equator (disregarding Earth's minor flattening by 0.3%). A circle of latitude is perpendicular to all meridians. The latitude of the circle is approximately the angle between the Equator and the circle, with the angle's vertex at Earth's centre. The equator is at 0°, and the North Pole and South Pole are at 90° north and 90° south, respectively. The Equator is the longest circle of latitude and is the only circle of latitude which also is a great
The Blood Line anything in the way that, say, some of the sacrifices in "Children of Earth" did.' He also criticised the effect of the cliffhanger, saying 'so it turns out that this huge world-changing event was just a "trial run" for an even bigger plan on the part of the bad guys? Does anyone (other than Davies) think that what the series needs is to get even bigger?' The Blood Line "The Blood Line" is the tenth and final episode of "", the fourth series of the British science fiction television series "Torchwood". It was first broadcast in the United States on