GeminiFocus July 2017 - Page 13

surrounded by subsidence. They also show a very turbulent region to the northwest of the Great Red Spot. The Subaru image is available here. The NASA Juno spacecraft was launched in August 2011 and began orbiting Jupiter in early July 2016. A primary goal of the mis- sion is to improve our understanding of Ju- piter — from its atmospheric properties, to our understanding of how Jupiter and other planets in the outer Solar System formed. Juno’s payload of nine instruments can probe Jupiter’s atmospheric composition, temperature, and cloud dynamics, as well as the properties of the planet’s intense mag- netic field and aurora. Gemini’s near-infrared images are particu- larly helpful to Juno’s Jupiter Infrared Au- roral Mapper (JIRAM). JIRAM takes images at 3.5 and 4.8 microns and moderate-reso- lution spectra at 2 - 5 microns. The Gemini images provide a high-resolution spatial context for JIRAM’s spectroscopic observa- tions and cover wavelengths and regions of the planet not observed by JIRAM. They also place an upper-atmospheric constraint on Jupiter’s circulation in the deep atmosphere determined by Juno’s Microwave Radiom- eter (MWR) experiment. Orton leads the observing team for the adaptive-optics imaging and Wong heads the observing team for the thermal im- aging. Additional team members include Andrew Stephens (Gemini Observatory); Thomas Momary, James Sinclair (JPL); Kevin Baines (JPL, University of Wisconsin); Mi- chael Wong, Imke de Pater (University of California, Berkeley); Patrick Irwin (Univer- sity of Oxford); Leigh Fletcher (University of Leicester); Gordon Bjoraker (NASA Goddard Space Flight Center); and John Rogers (Brit- ish Astronomical Association). In the full campaign of Earth-based support, the Gemini observations provide a key ele- July 2017 ment that extends the spectral coverage of other facilities, as well as providing a stra- tegic sampling to compare with the lower- resolution but more frequent imaging by NASA’s Infrared Telescope Facility (IRTF) that tracks the evolution of atmospheric features. These Gemini data are also a useful measure of cloud properties to compare with mid-in- frared thermal imaging and spectroscopy of Jupiter’s atmosphere, such as that provided by Subaru’s COMICS experiment. The space platforms involved in the Juno-support campaign include the XMM, Chandra and NuSTAR X-ray observatories, and the Hisaki ultraviolet observatory, together with the Hubble Space Telescope. The many ground- based observatories include the Very Large Telescope (VLT), the Atacama Large Millime- ter Array (ALMA), Calar Alto Observatory, and a suite of visible and radio observatories. Full details of the campaign can be found here. Figure 3. At longer infrared wavelengths, Jupiter glows with thermal (heat) emission. In dark areas of this 4.8-micron image, thick clouds block the emission from the deeper atmosphere. The Great Red Spot is visible just below center. This image, obtained with the Gemini North telescope’s Near-InfraRed Imager (NIRI), was obtained on January 11, 2017, so the relative positions of discrete features have changed with respect to the near-infrared image in Figure 1. Image credit: Gemini Observatory/AURA/NSF/ UC Berkeley Peter Michaud is the Public Information Out- reach Manager of Gemini Observatory. He can be reached at: [email protected] GeminiFocus 11