Aurora

	Polar Visible Aurora Animation: July 16, 2000 This animation of a visible aurora in the northern hemisphere was captured on July 16, 2000 by the Polar satellite. This aurora was visible as far south as Florida and Texas.
	Why Do We See Red in the Sky? Auroras get their color from the various elements in our atmosphere, like oxygen and nitrogen. When charged particles from the sun hit theses elements, they excite the atoms, causing them to give off light. Different atoms give off different colored light when they become excited, as this animation shows.
	What Makes Aurora's dance? In 2008, observations from the THEMIS mission confirmed for the first time that magnetic reconnection in the magnetotail trigger the onset of substorms. This animation illustrates this discovery, which asserts that a substorm’s onset follows a particular pattern: a period of reconnection, followed by rapid auroral brightening and rapid expansion of the aurora toward the poles, culminating in a redistribution of the electrical currents flowing in near-Earth space.
	THEMIS Ground Stations A collection of ground-based All-Sky Imagers (ASI) captures the aurora brightening caused by a substorm. This network is an important part of the THEMIS mission and is considered the sixth satellite.
	Auroral Substorms from Space NASA’s Polar spacecraft captures auroral substorms from space.