File:HL Tauri Polarized (15194346379).png

This is my old friend that won third place in the Hidden Treasures contest, but this time in polarized light. I decided to revisit XZ Tauri to see if I had missed anything previously and discovered a series of polarized observations. What the heck is polarized light? What does it mean? Why is this thing looking like a rainbow? I'm not going to lie; the answers to these questions largely elude me but for a general idea, Zolt is here to help. Have a look.

Interestingly, only HL Tauri seems strongly affected by the polarized filters. That's the rainbow-colored bit of cloud in the center. XZ Tauri, the double star (Yes, it is hard to see the second star) on the left, is monochrome in contrast which I presume means that its light simply isn't polarized. The star illuminating the central nebula isn't even visible, here. It's just under that u-shaped arc of brightest cloud. The F606W filter used collected red light. In order to see the point source behind the cloud, infrared must be used. There are some NICMOS observations in the archive which reveal it, but those data are not used for this picture. The bright bit on the right is a young stellar object (YSO) which just means it's a baby star. Its light seems vaguely polarized but it's hard for me to tell.

I do not know what those small white dots are. If I had to guess I would say they are stars just behind the dust extincted just enough that they are still visible to Hubble.

Note I did increase the saturation on this because the point is missed if the colors are just barely perceptible, which they originally were.

Red: ACS / WFC F606W POL120V Green: ACS / WFC F606W POL60V Blue: ACS / WFC F606W POL0V