A Possible Cause for the Cool Homopause of the 8-micron North Polar Hot Spot of Jupiter

We have found cool homopause temperatures (Kim et al. 2016) of 180 - 250 K for the 8-micron North Polar Hot Spot (8NPHS) of Jupiter, which has been observed to be stationary at 180 deg (SysIII) longitude since the early 1980s. The 3-micron spectro-images of Jupiter that we analyzed were obtained with GNIRS, Gemini Near-Infrared Spectrograph at Gemini North on January 13, 2013(UT), and at $8{\mu}m$ on Feburary 6, 2013(UT) with TEXES, the Texas Echelon Cross Echelle Spectrograph at the NASA IRTF. The cool homopause was unexpected, and a possible implication of the relatively cool 8NPHS homopause compared with those of other auroral regions will be presented.