Phosphine has long been held as evidence of turbulent mixing in Jupiter ’ s atmosphere . In chemical equilibrium , phosphine is converted to phosphorus trioxide at temperatures less than ~ 1,000 K . In Jupiter , hot phosphinerich gas from the interior is mixed into the photosphere at a faster rate than the phosphine is destroyed . WISE 0855 does not show the same mixing behavior , despite the fact that it is warmer than Jupiter and should not have to mix phosphine as far . This result will be studied in more detail in a future paper .
Future Explorations
Gemini was designed to do thermal infrared spectroscopy , and Maunakea is the best site on Earth to do it . From the telescope , to the weather , to the instrument and observers , a lot had to work right to complete this observation . It ’ s a testament to Gemini that when WISE 0855 was discovered , GNIRS was ready and able to obtain a spectrum for our team ’ s work .
Andy Skemer is an Assistant Professor at the University of California Santa Cruz . He can be contacted at : askemer @ ucsc . edu
WISE 0855 will be an early target of the James Webb Space Telescope ( JWST ). But surprises in its spectrum suggest that we need to continue iterating our theoretical understanding of cold brown dwarfs and exoplanets before JWST launches ( Figure 3 , lower right ). This Is Gemini done with WISE 0855 ? Hopefully not ; having solved many of the technical problems that make faint thermal-infrared spectroscopy so difficult , we have been allocated time to pursue its 3.8- 4.1 micron spectrum . At these wavelengths , we expect to see the influence of methane chemistry instead of water chemistry , and we will refine estimates of WISE 0855 ’ s luminosity , which directly impacts its temperature and mass .
We also are continuing to study the coldest brown dwarfs at M-band . Previous observations only went down to 700 K . There ’ s a big jump from 700 K to 250 K , which we expect contains the formation of water clouds . With five more brown dwarfs spanning the 250- 700 K gap , we hope to study the depths of water absorption lines , which models predict will increase with decreasing temperature until water clouds start to mute them , and / or remove a significant fraction of the available water vapor .
10 GeminiFocus January 2017 | 2016 Year in Review