The Juno Mission and the Role of Supporting Earth-‐Based

The Juno Mission and the Role of Supporting Earth-Based Observations

Glenn Orton Jet Propulsion Laboratory California Institute of Technology My own experienceor planets: includes work with IR instruments on spacecraft

Pioneers 10 and 11 to Jupiter and Saturn (1973, 1974) ! INFRARED RADIOMETER Galileo to Jupiter (1996-2003) ! - Near-Infrared Spectrometer - Photo-polarimeter/Radiometer Cassini to Saturn (2005-present)) ! Composite Infrared Spectrometer (CIRS) Visible/Near-Infrared Mapping Spectrometer (VIMS) …and on ground-based telescopes:

W.M. Keck Telescopes 10-meter diameter (the 2nd biggest in the world) ↓ ↓ NASA Infrared Telescope Facility (IRTF) 3-meter diameter ↓

↑ Subaru (Japanese National Astronomical Observatory) 8.2-meter diameter European Southern Observatory (Chile): Very Large Telescope

(next: a “tour” of my infrared solar system) Remote Observation on NASA’s IRTF ROADMAP • The Juno mission – Summary – Status – Orbit plans • The supporting role of Earth-based observations – Different aspects – Priorities Juno Science Objectives

Juno will improve our understanding of the history of the solar system by investigating the origin and evolution of Jupiter. ! To accomplish this goal, the mission will investigate Jupiter’s Interior, Atmosphere and Magnetosphere. ! What we learn from Juno also will vastly improve our general knowledge of how giant planets form and evolve, shaping the evolution of planetary systems everywhere. Probing the deep interior from orbit

Juno maps Jupiter from the deepest interior to the atmosphere using microwaves, and magnetic and gravity fields. Sensing the deep atmosphere (Pt1) Juno’s MicroWave Radiometer (MWR) measures thermal radiation from the atmosphere to as deep as 1000 atmospheres pressure (~500-600 km below the visible cloud tops). Determines water and ammonia abundances in the atmosphere all over the planet

Synchrotron radio emission from the radiation belts makes this kind of measurement impossible from far away on Earth Mapping Jupiter’s gravity Tracking changes in Juno’s velocity reveals Jupiter’s gravity (and how the planet is arranged on the inside).

Precise Doppler measurements of spacecraft motion reveal the gravity field. ! Tides provide further clues.

Microwave Radiometer— MWR (JPL) UV Spectrometer— UVS (SwRI) Infrared Camera— JIRAM (ASI) Visible Camera— JunoCam (Malin) key remote-sensing instruments:

Microwave Radiometer— MWR (JPL) UV Spectrometer— UVS (SwRI) Infrared Camera— JIRAM (ASI) Visible Camera— JunoCam (Malin) MWR orbits have the spacecraft (S/C) oriented to point to nadir. ! Gravity-Mapping orbits have the S/C oriented so the high-gain antenna (HGA) points directly at the Earth ! MWR orbits are early in the mission to avoid radiation damage in later orbits. ! MWR, JIRAM, JunoCAM and the UVS teams still plan to remain turned on during gravity-mapping orbits, so there may be some data obtained on GS orbits, but not at nadir angles. ! Juno will concentrate remote- sensing plans on orbits 3, 5-8, but may get more useful data. • Compare orbit 3: GS vs. MWR tilt

GS Tilt MWR Tilt

Effect of GS tilt is to skew JunoCam FOV into more sunlit atmosphere – not a problem! EVENT DATE JUPITER-SUN EVENT DATE JUPITER-SUN ANGLE ANGLE Orbit 2 PJ 2016 Oct 16 15°W Orbit 19 PJ 2017 May 5 150°E IRTF-accessible 2016 Oct 31 27°W Orbit 20 PJ 2017 May 16 139°E Orbit 3 PJ 2016 Nov 10 35°W Orbit 21 PJ 2017 May 27 128°E 30-min point 2016 Nov 12 * Orbit 22 PJ 2017 Jun 7 117°E Orbit 4 PJ 2016 Nov 21 44°W Orbit 23 PJ 2017 Jun 18 106°E HST min. solar-avoidance angle 50°W Orbit 24 PJ 2017 Jun 29 96°E Orbit 5 PJ 2016 Dec 2 54°W Orbit 25 PJ 2017 Jul 10 87°E Orbit 6 PJ 2016 Dec 13 66°W Orbit 26 PJ 2017 Jul 21 77°E Orbit 7 PJ 2016 Dec 24 73°W Orbit 27 PJ 2017 Aug 1 68°E Orbit 8 PJ** 2017 Jan 4 83°W Orbit 28 PJ 2017 Aug 11 60°E Orbit 9 PJ 2017 Jan 15 93°W Orbit 29 PJ 2017 Aug 22 51°E Orbit 10 PJ 2017 Jan 26 103°W HST min. solar-avoidance angle 50°E Orbit 11 PJ 2017 Feb 6 114°W Orbit 30 PJ 2017 Sep 2 42°E Orbit 12 PJ 2017 Feb 17 125°W Orbit 31 PJ 2017 Sep 13 34°E Orbit 13 PJ 2017 Feb 28 137°W Orbit 32 PJ 2017 Sep 24 25°E Orbit 14 PJ 2017 Mar 11 149°W Orbit 33 PJ 2017 Oct 5 17°E Orbit 15 PJ 2017 Mar 22 161°W Orbit 34 Deorbit 2017 Oct 16 8°E Orbit 16 PJ 2017 Apr 2 173°W ! Orbit 17 PJ 2017 Apr 13 174°E ! Orbit 18 PJ 2017 Apr 24 162°E ! ! Remote-Sensing (MWR) Orbits *Jupiter available for 30 min for airmass<2.0 Gravity-Sensing (GS) Orbits **with tilt What does Juno need in remote-sensing support? • Help in predicting the locations of features Predicting feature locations

• End of 5-year cruise to Jupiter in 2016 July • Need to know ~5-6 months ahead of this arrival the timing of the initial perijove (PJ) • So location of features must be based on predictions from data before 2016 Jan-Apr (the 2015-2016 apparition) • Use this information to plan initial orbit timing • ± 20 min • ± 12° of longitude • Features of interest: • Great Red Spot (generally easy to predict) • 5-μm hot spots (not so easy) This is important to understand the relationship between the results from the Galileo probe, which descended into a 5-μm hot spot and MWR results – the driest region on the planet. Adopt 5-μm Prediction Scheme Used for Galileo 5-micron emission from cloud tops HST (F763M) 5-micron emission from cloud tops What does Juno need in remote-sensing support?

• Contextual observations over the globe – Are those narrow regions JIRAM, MWR sensing a part of wave structure? – Are they representative of global-mean properties? • Context in time – What has been the evolution of these features? – What is the relationship between the properties detected in the upper atmosphere and the deeper atmosphere? • Observations in spectral regions not included in Juno instrumentation – mid-infrared • Temperatures • Indirect tracers of vertical motions (clouds, abundances of condensable, disequilibrium gases) – Higher spectral resolution in the “CCD” range (up through 2 µm) Track of MWR and JIRAM Sensing One longitudinal swath

• A pole-to-pole swath of images (15) is possible. • But this is not a requirement – EPO will select positions • MWR orientation This is JunoCam’s entire coverage of Jupiter if observing ends at Orbit 8. What does Juno need in remote-sensing support?

• Help in predicting locations of features • Contextual observations over the globe – Are those narrow regions JIRAM,MWR sensing a part of wave structure – Are they representative of global-mean properties • Context in time – What has been the evolution of these features? – What is the relationship between the properties detected in the upper atmosphere and the deeper atmosphere? • Observations in spectral regions not included in Juno instrumentation – mid-infrared • Temperatures • Indirect tracers of vertical motions (clouds, abundances of condensable, disequilibrium gases) – Higher spectral resolution in the “CCD” range (up through 2 µm) Example: Great Red Spot

• Agnes Clark: 1879 • Etienne Trouvelot: 1879 1995 WFPC2 Example: Great !Red Spot ! • Accelerated shrinking ! ! ! ! ! 2009 WFC3/UVIS ! ! ! ! ! ! 2014 WFC3/UVIS Pink Spot ?

color composite 2.3 µm

2013 Nov. 15 Example: Jupiter’s “Faded” South Equatorial Belt

2009: July 23 October 20 November 7

2010: April 19 August 30 A. Wesley images 5-µm Imaging of an SEB Fade – seeing through near-infrared eyes

20 July 2009 6 August 2009 27 August 2009

SEBn SEBs GRS

25 June 2010 5 September 2010 - SEB “fade” as early as mid-2009 in the deep atmosphere

GRS➔ ! GRS➔ - é Oval BA

IRTF/NSFCam2 imaging 2009-2010 Starting in November 2010, the SEB began “reviving” its old dark color. ! ! ! ! !

23! July 2009 6 June 2010 11 August 2011

Understanding the revival provides clues both to Jovian dynamics !! ! and to the chemistry of its cloud system. ! ! • Later in 2010-2011. • Further changes of physical properties: – NEB has narrowed in latitude – NTB has clouded over

RGB 4.8 μm 8.7 μm Example of Visible-Infrared Comparisons: 2012 Aug 19-23 (visible images compiled by Marco Vedovato) What does Juno need in remote-sensing support?

• Contextual observations over the globe – Are those narrow regions JIRAM,MWR sensing a part of wave structure – Are they representative of global-mean properties • Context in time – What has been the evolution of these features? – What is the relationship between the properties detected in the upper atmosphere and the deeper atmosphere? • Observations in spectral regions not included in Juno instrumentation – Mid-infrared • Temperatures • Indirect tracers of vertical motions (clouds, abundances of condensable, disequilibrium gases) - Higher spectral resolution in the “CCD” range (up through 2 µm) Juno’s spectral grasp:

• JIRAM – 2-5 µm (near-infrared spectrum) • MWR – 1.3-50 cm (microwave spectrum) • UVS – 70-205 nm (ultraviolet spectrum) • JUNOCAM (public-outreach CCD camera: RGB+890 nm filters) ! • Missing: • Mid-IR (thermal) – Temperatures in the upper-tropopshere and stratosphere – Clouds at the ammonia-ice conensation level – Composition in the upper tropopshere Example of optimal mid-Infrared imaging of Jupiter, e.g. 7.8 µm 17.9 µm stratospheric temperatures tropospheric temperatures

Subaru/COMICS observations of Jupiter 2013 February 27 ! Example of contemporaneous multi-platform amateur and professional observations

2011 Aug 27, 8.6 μm 2011 Aug 29, 4.8 μm Subaru, COMICS IRTF, NSFCam2

2011 Aug 28, visible A. Kazemoto, Kyoto

Junocam:

Has no scientific-grade calibration and will be taking images depending on the ‘votes’ of the general public. ! This is good for the public, including amateur astronomers but not optimal for the science team, who would prefer imaging along the spacecraft track. ! Narrow-band images and This is a simulation of a Junocam spectra in the CCD range image 72 hours before perijove. Junocam has 4 filters: B ,G, R and 890-nm (‘methane’) ! These sense what the human eye can see, but the G and R filters aren’t particularly useful for understanding cloud structure because they sense sunlight reflected from clouds in and out of bands of gaseous methane. ! The 890-nm filter will be more useful in this sense. But it would be good to resolve reflection spectrally in the various bands and the continuum between them. What observations are useful? ! Spatially resolved spectra of atmospheric features CCD-based spectrometers is maturing greatly. ! LISA (Pic-du-Midi) Sources of Data Sources of Data – Amateur Observers

• Potentially large cadre of observers, immense interest by some quite accomplished amateurs feeling involved with a NASA mission – lots of motivation • Communication with amateur session at EPSC – presentation was broadcast to Astronomy Education Alliance meeting: http://live.fccn.pt/nuclio/aeam/ – Contact with IAU Chair of Pro-Am Relations Sources of Data – Amateur Observers

Anthony Wesley JUPOS / WinJUPOS team, headed by Grischa Hanh Logistics/Formatting

• Do not stretch the images or change the linearity – Turn OFF the histogram stretching before registering and stacking the images • Save in FITS, PNG or TIFF formats – Ask for highest-depth option – This preserves linearity, which JPEG and GIF destroy • IMS text file with each image – Generated within WinJUPOS – Who made the image, where, what time, which filter • Send a “sharpened” image if you want, but send something has not been subject to a wavelet or an unsharp-masking procedure. • Cylindrical maps flattened by Lambertian law – This is an option within WinJUPOS • Compress results (zip file) • Grischa Hahn and JUPOS group have made some of these automatic options within WinJUPOS. • Observer’s options for archiving: – Current: PVOL – Juno site, which might display the images rapidly when deposited and allow immediate access by the Juno team – Practice in the upcoming apparition, submissions in March-June of 2015 We will take all images, but recommend the video approach that uses RegistaX or AutoStakkert

-suggested by Anthony Wesley Selects and aligns the best frames.

-suggested by Anthony Wesley Further stability using WinJUPOS: Project different colors onto latitude-longitude grid, combine and reproject onto a spheroid. Some extraordinary images can result.

! ! ! ! ! ! ! ! ! ! A. Wesley

Wayne Jaeschke: full-daylight observation: 2013 April 9 Sources of Data – Amateur Observers

• Potentially large cadre of data, immense interest by some quite accomplished amateurs in quasi-involvement with a NASA mission – lots of motivation • Communication with amateur session at EPSC – Contact with IAU Chair of Pro-Am Relations – We will be interested in anything you provide – We will be happiest with data in specific format • Plan is to curate these observations within Juno – Web site with instructions – Create a Juno-friendly and observer-friendly site – Ideally, amateurs can see their contributions within 24-36 hours – Note that this would be different from PVOL, where there are no image “thumbnails”. Amateur Involvement • “Serious” amateur interest group, headed by Chris Go, Cebu City, Philippines ! Thanks to all the observers ! Broader list of amateur Jupiter observers around the world. Sources of data – professional: HST

• New program from Space Telescope Science Institute (“OPAL”) – Outer Planet Atmospheres Legacy program – Two sets of observations at strategic wavelegnths repeated once for a time separation that allows for winds to be determined by feature tracking • Set the Jupiter set to be coincident with MWR (or GS) orbits? • Potentially more observations for Juno support? • UV (auroral) observations – Spatial and temporal context for Juno’s UVS – Independent value of high-cadence observations simultaneously with Juno’s in-situ particle and field measurements + – Contemporaneous observations with 3.454 µm H3 emission – Contemporaneous observations with mid-IR auroral response of hydrocarbon emission Sources of data – professional: CCD filtered imaging

– Calar Alto, Univ. del Pais Vasco group, using rapid imaging – IRTF MORIS (CCD attached to near-IR spectrometer SpeX) – Royal Thai Observatory (connection via Chris. Go) • Thailand • Chile – Pomona College (Bryan Penprase, Franklin Marsh) • Brackett Observatory, Claremont • Table Mountain (soon with an AO system) – Lulin Observatory, Taiwan (Wing Huen Ip) – Lebanese-American University (Nelly Mouawad) – Langkawi Observatory, Malaysia (Mohammad Redzuan B. Tahar) – Palomar 60” using Robo-AO (Z’, I’, R’ filters) – U. Hawaii 88” (AO system coming on line?) Christophe Baranec Sources of data – professional: Ground-based visible

• Storage of CCD results – Pomona College – Volunteered to store all professional images for Juno – Principal contact with interested astronomers at observatories in Turkey and Lebanon ! • Imaging filters in the CCD range

– Very useful: filters sensing moderate to weak CH4 absorption at 890nm, 710nm, 620nm+ nearby pseudo-continua – Juno will not supply filters ! • Spectroscopy Sources of data – professional: CCD spectroscopy

– Apache Point Obs., NM State Univ. (Nancy Chanover), filtered imaging via tunable diode laser – Univ. of Narino Obs., Columbia (Alberto Quijano Vodniza), grating spectroscopy with SBig CCD [referral from Adriana Ocampo] ! – Very Large Telescope (MUSE), open availability • Just finished testing mode, including Jupiter imaging • Spectral range: 465-930 nm • R = 2000-4000 • 0.2” pixel • Each frame took 0.1 sec of integration • AO capability to be tested in fall of 2015 • Proposal for 2015 spring by P. Irwin, L. Fletcher (Oxford), G. Orton (JPL) granted VLT time ESO Very Large Telescope: MUSE

– Early test results, 2014 February 17 Near-Infrared Support

• IRTF NSFCam – 0.9-5.2 µm imaging instrument – Responsible for 5-µm and other images used to make decisions about Galileo remote-sensing targets – NSFCam2 is refurbished version of NSFCam – Circular-variable filter allowed the observer to ‘dial’ to any wavelength with 2-2.5% resolution, plus some discrete filters – Suffered a cryogenic explosion in 2014 February, following a power-outage affecting the entire summit of Mauna Kea – IRTF does not intend to repair the instrument in time for the Juno mission ! • IRTF SpeX guide camera, capable of scientific-grade imaging – Smaller selection of discrete filters – Fortunately 5-µm filter is one of them – Otherwise slit-scanning at a similar resolution (tested Oct 15-16) – Gemini, Keck, VLT instruments have similar filters, but much harder to get observing time Difficulty with Mid-Infrared Support

• Mid-infrared facility instruments have become rare – Keck Long-Wavelength Spectrometer decommissioned in 2004 – Gemini South TReCS, Gemini North Michelle, unplugged for financial reasons – VLT VISIR, down for refurbishment, performed worse after returning, so down again possibly back up in early 2015 (under testing with 10” throw) • Functioning, COMICS at the 8-m Subaru Telescope – Extremely good data, both imaging and spectroscopy – Recent policy change, “as a non-Japanese PI, you are at a disadvantage” – So for semester 2015A, Orton submitted as a co-I and a Japanese collaborator submitted as a PI (proposal not granted time) • Functioning, CanariCam at the 10.4-m Gran Telescopio Canarias – Slow beginning, proposals accepted to observe Jupiter for the first time; collaboration with the University of the Basque Country group in Bilbao, Spain – Not a low-water-vapor site, so what’s possible will remain to be tested • At a NASA Outer Planet Assessment Group meeting, Curt Niebur (NASA HQ) noted that I shouldn’t see the lack of US facilities as a problem in supporting Juno. – Can we get institutional support, via any NASA/JAXA/NAOJ connections? Other Mid-Infrared Approaches

• Non-facility instruments – Smaller telescopes mean worse diffraction limits, closer to 1.8” than the 0.4” at 8-10 meter-class telescopes. – CELESTE, operating at Kitt Peak – TEXES, a high-resolution scanning mid-infrared spectrometer, operating mostly at the IRTF, occasionally Gemini North TEXES spectral images of Jupiter 2013 February 1-11 ! Tracking the QQO in the stratospheric temperature field 960 cm-1 spectra and imaging (PH ) 3 2012 Jan 0 7 9 ! ! 5 ) 6 1 9 −

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2 1 − 2014 December 7-8 UT, TEXES at NASA’s IRTF

T(300 mbar) T(100 mbar) NH3 VMR (300 mbar) cloud opacity (600 mbar)

T(10 mbar) Electromagnetic Field Monitoring • Single-dish observations to monitor synchrotron radiation • Very Large Array – Simultaneous observations to track entire magnetic field • Monitoring indirect influences on magnetic field and plasma field behavior – Solar-wind measurements – Io outburst monitoring (spectroscopy or H, K, L-band comparisons) – Io torus spectroscopic observations: SII @ 671.6, 673.1 & 406.9, 407.6 nm; OII @ 372.6, 372.9 nm; SIII @ 372.2, 631.2 nm and resonantly scattered NaI @ 589.0, 589.6 nm (maps of electron density, T, and ion abundances) Summary of Issues - Atmosphere

• What is the desired cadence of HST observations? • To what extent could ground-based observations supplement these with narrow-band CCD imaging? • To what extent can we get CCD spectroscopy? • Where can we get near-infrared facilities outside the IRTF? • What strategy can we use to get mid-infrared imaging, spectroscopy at facilities other than the IRTF? • Where can we get microwave/radio observations that are useful (VLA only)? Summary of Issues - Magnetosphere

• Can we develop a unified campaign of HST UV observations of Jovian aurorae? + • Can we develop a unified campaign of H3 monitoring at the other observatories besides the IRTF? • How do we develop a source of information on Io outburst activity, which severely perturbs the electromagnetic field? Can we monitor the Io torus? So we have a lot to figure out and time is growing short. But I’m not discouraged. ! One year before the Juno launch, when things didn’t seem to be going on schedule, and people on the Juno project were getting worried, there appeared an invitation to the One-Year-To- Launch Party – to pick people’s spirits up: ! S Glenn Orton ! IF EVERYTHING SEEMS UNDER CONTROL -

Glenn Orton ! IF EVERYTHING SEEMS UNDER CONTROL - YOU AREN’T GOING FAST ENOUGH.

Glenn Orton ! IF EVERYTHING SEEMS UNDER CONTROL - YOU AREN’T GOING FAST ENOUGH. ! -Mario Andretti

Glenn Orton

Thanks!

glenn.orton@jpl.nasa.gov Supplemental Information EVENT DATE JUPITER-SUN EVENT DATE JUPITER-SUN ANGLE ANGLE Orbit 2 PJ 2016 Oct 16 15°W Orbit 19 PJ 2017 May 5 150°E IRTF-accessible 2016 Oct 31 27°W Orbit 20 PJ 2017 May 16 139°E Orbit 3 PJ 2016 Nov 10 35°W Orbit 21 PJ 2017 May 27 128°E 30-min point 2016 Nov 12 * Orbit 22 PJ 2017 Jun 7 117°E Orbit 4 PJ 2016 Nov 21 44°W Orbit 23 PJ 2017 Jun 18 106°E HST min. solar-avoidance angle 50°W Orbit 24 PJ 2017 Jun 29 96°E Orbit 5 PJ 2016 Dec 2 54°W Orbit 25 PJ 2017 Jul 10 87°E Orbit 6 PJ 2016 Dec 13 66°W Orbit 26 PJ 2017 Jul 21 77°E Orbit 7 PJ 2016 Dec 24 73°W Orbit 27 PJ 2017 Aug 1 68°E Orbit 8 PJ** 2017 Jan 4 83°W Orbit 28 PJ 2017 Aug 11 60°E Orbit 9 PJ 2017 Jan 15 93°W Orbit 29 PJ 2017 Aug 22 51°E Orbit 10 PJ 2017 Jan 26 103°W HST min. solar-avoidance angle 50°E Orbit 11 PJ 2017 Feb 6 114°W Orbit 30 PJ 2017 Sep 2 42°E Orbit 12 PJ 2017 Feb 17 125°W Orbit 31 PJ 2017 Sep 13 34°E Orbit 13 PJ 2017 Feb 28 137°W Orbit 32 PJ 2017 Sep 24 25°E Orbit 14 PJ 2017 Mar 11 149°W Orbit 33 PJ 2017 Oct 5 17°E Orbit 15 PJ 2017 Mar 22 161°W Orbit 34 Deorbit 2017 Oct 16 8°E Orbit 16 PJ 2017 Apr 2 173°W ! Orbit 17 PJ 2017 Apr 13 174°E ! Orbit 18 PJ 2017 Apr 24 162°E ! ! Remote-Sensing (MWR) Orbits *Jupiter available for 30 min for airmass<2.0 Gravity-Sensing (GS) Orbits **with tilt • Juno Mission Orbit Plan ! • Jupiter Orbit Insertion (JOI) 2016 July 5 • Orbit 1 lower apojove perijove 2016 August 3 • Orbit 2 “cleanup orbit” perijove 2016 October 16 • Orbit 3 MWR orbit (remote sensing) perijove 2016 November 10 • Orbit 4 gravity orbit perijove 2016 November 21 • Orbit 5 MWR orbit (remote sensing) perijove 2016 December 2 • Orbit 6 MWR orbit (remote sensing) perijove 2016 December 13 • Orbit 7 MWR orbit (remote sensing) perojove 2016 December 24 • Orbit 8 MWR orbit (remote sensing) perijove 2017 January 4 • Orbit 9 gravity mapping orbit perijove 2017 January 15 • … • Orbit 32 gravity mapping orbit perijove 2017 September 24

Another example, coordinated observations of a series of alternating upwelling (cloudy) and downwelling (clear) regions in the SEB ‘revival’ (re-darkening)

RGB, Don Parker

Most regions that are bright at 4.68 μm are visibly dark.

Color Composite of Images from the Amateur Community

HST (F275W)