Latitude constant latitude and constant longitude, which are constructed with reference to the rotation axis of the Earth. The primary reference points are the poles where the axis of rotation of the Earth intersects the reference surface. Planes which contain the rotation axis intersect the surface at the meridians; and the angle between any one meridian plane and that through Greenwich (the Prime Meridian) defines the longitude: meridians are lines of constant longitude. The plane through the centre of the Earth and perpendicular to the rotation axis intersects the surface at a great circle called the Equator. Planes parallel to the
The Last Dog on Earth appeal to teen readers. "The Last Dog on Earth" was included in the "What Ails You?" category, comprising literature "about how diseases, disorders, and other general health related symptoms affect our lives". In a 2005 interview, Daniel Ehrenhaft mentioned that a school in Chicago created an extracurricular activity wherein "kids designed games and gadgets", having been inspired by Logan's hobby of inventing devices. "The Last Dog on Earth" has received mixed reception from critics, who have praised the plot, but criticized the heavy use of coincidences to advance the plot. "Kirkus Reviews" commented that "happenstance plays a large role in