Planum Boreum

Planum Boreum
	Viking mosaic of Planum Boreum and surrounds
Coordinates	88°00′N 15°00′E / 88.0°N 15.0°E

Planum Boreum (Latin: "the northern plain") is the northern polar plain on Mars. It extends northward from roughly 80°N and is centered at 88°00′N 15°00′E / 88.0°N 15.0°E / 88.0; 15.0. Surrounding the high polar plain is a flat and featureless lowland plain called Vastitas Borealis which extends for approximately 1500 kilometers southwards, dominating the northern hemisphere.^[1]

^ [1] and [2] give Vastitas Borealis starting at 54.7°N and Planum Boreum at 78.5°N. The radius of Mars is approximately 3400 km, so $d={\frac {78.5-54.7}{360}}\times 2\pi \ \times 3400{\mbox{ km}}=1412{\mbox{ km}}$

[1] [1] and [2] give Vastitas Borealis starting at 54.7°N and Planum Boreum at 78.5°N. The radius of Mars is approximately 3400 km, so $d={\frac {78.5-54.7}{360}}\times 2\pi \ \times 3400{\mbox{ km}}=1412{\mbox{ km}}$

[1]

Viking mosaic of Planum Boreum and surrounds
Coordinates	88°00′N 15°00′E / 88.0°N 15.0°E / 88.0; 15.0