Monday, August 27, 2012

The Mantis Shrimp: A Miniature SDO?

SDO takes pictures of the Sun in many wavelengths and uses the polarization of the light to measure the magnetic field of the Sun. Then we are forced to rely on the human eye to look at our images. The human eye uses three color sensors to see millions of colors. We don’t see polarized light any different than non-polarized without special sunglasses. Polarized light has the light waves moving in one direction. Glare is light moving side-to-side so sunglasses that let light through that is moving up and down can keep glare out of your eyes. But we usually don't worry about polarized light.

Is there an eye that could better enjoy SDO images? Yes! The mantis shrimp.
These arthropods have up to 12 different color sensors and can see light from the ultraviolet to the infrared (see an amazing closeup of the eyes at the National Geographic.) Two channels see shapes and the rest look at colors. One set of eye cells can measure the polarization of the light. They can see about 10 times more colors over a wider range of wavelengths than humans.

Rather than the 3-color composites we now display (such as this one from today), we could display AIA and HMI images in a 12-color display. A mantis shrimp might enjoy watching for flares and coronal mass ejections!

We don’t understand why a mantis shrimp needs this optical equipment. They live in the brightly colored tropical oceans. Maybe they need to see the differences between friend, foe, and food. Some fish glow in ultraviolet light, perhaps that is another signal the shrimp watch for. The polarized light might reveal semi-transparent fish to a hungry mantis shrimp. Sounds like they have their own real-time feature finding team built into their eyes.

Perhaps we could adapt the multi-wavelength viewing used by the mantis shrimp to find out what is happening on the Sun.

Check out the July 30, 2012 episode of RadioLab to hear more about how different animals see color.