Jupiter Is Watching You This Halloween

Watching, waiting.

The Hubble Space Telescope was minding its own business, doing space things, when suddenly...

NASA, ESA, and A. Simon (Goddard Space Flight Center) / Via Flickr: gsfc

...it found Jupiter staring straight back at it.

The Hubble was monitoring the Great Red Spot, a vortex of gases that has been swirling since at least the 1830s.

Then one of Jupiter's moons cast a shadow on the storm, giving it a pupil.

NASA/JPL/DLR

Ganymede (left) is the largest moon in the solar system and is even bigger than Mercury and Pluto. It is one of the Galilean satellites (right), four huge moons of Jupiter that Italian astronomer Galileo Galilei spotted hundreds of years ago.

The image was taken back in April but just released this past week.

Fun fact: The Great Red Spot is so big it could swallow Earth.

NASA / Reuters

It's a mere 10,000 miles (16,000 km) across, making it nearly twice the diameter of our blue marble. As NASA puts it: If the sun were as tall as a standard front door, the Earth would be as small as a nickel and Jupiter would be about the size of a basketball. Jupiter is also a gas giant, meaning it doesn't have a solid surface.

Jupiter is ready for Halloween.

NASA, ESA, and A. Simon (Goddard Space Flight Center) / Via Flickr: gsfc

Are you?