[1] The main feature of the Planum Boreum is a large fissure or canyon in the polar ice cap called Chasma Boreale.

Planum Boreum interfaces with Vastitas Borealis west of Chasma Boreale at an irregular scarp named Rupes Tenuis.

[5] It has a volume of 1.2 million cubic kilometres and covers an area equivalent to about 1.5 times the size of Texas.

The troughs are roughly perpendicular to the wind direction, which is shifted by the Coriolis effect, leading to the spiral pattern.

[7] Chasma Boreale is a canyon-like feature older than the troughs, and in contrast is aligned parallel to the wind direction.

[9] The Phoenix lander, launched in 2007, arrived at Mars in May 2008 and successfully landed in the Vastitas Borealis region of the planet on May 25, 2008.

[12][13] A large doughnut-shaped cloud appears in North polar region of Mars around the same time every Martian year and of about the same size.

[15] The cloud is thought to be composed of water-ice,[15] so it is white in color, unlike the more common dust storms.

[15] Cyclone-like storms were first detected during the Viking orbital mapping program, but the northern annular cloud is nearly three times larger.