Present:
Glenn Orton, Chair
Robert West, Permanent member
Chris Russell, Permanent member
Imke de Pater, Permanent member
Heidi Hammel, Chair of Uranus and Neptune discipline
Paul Steffes, Chair of lab. spectroscopy discipline
Henry Roe, Chair of Titan discipline
John Clarke, *new* Chair of Io Torus, Magnetospheres, Aurora discipline
Franck Marchis, Chair of satellites (Io) discipline

Missing:
Agustin Sanchez-Lavega, Chair of Jupiter and Saturn Atmospheres discipline (he forgot)
Kevin Baines, Rotating Member (Chair forgot to inform him; mea culpa)

Pursuant to the last S.C. meeting, we commended the current work done by the chairs of the Auroral, Io Torus and Magnetospheres disciplines and reforulated these (now very small) groups into a single discipline. The chair invited John Clarke to head the discipline; he agreed and was present.

John spoke briefly about the International Heliophysical Year (IHY) effort. The effort in general is coordinated on the 50th anniversary of the International Geophysical Year (IGY) which was seminal in creating a coordinated undestanding of the earth's environment. This would focus on the solar envirnoment, specifically the solar wind and comparative planetology. His HST observations would almost exclusively use the ACS solar-blind camera to map time dependece of auroral-related phenomena in Jupiter and Saturn.

This effort would intersect with the ground-based work that is planned for supporting the science observations of New Horizons in Jan - May, 2007, centered on the Feb. 28 closest approach. Neutral atmospheric science for Jupiter is centered on the Great Red Spot and turbulent downwind region, with some observations of clouds in Oval BA (the "Little Red Spot").

John Spencer was scheduled to conduct and information and coordination meeeting after lunch later the same day. Randy Gladstone has Chandra and XMM-Newton observations of X-ray emission from Jupiter which is also scheduled in a coordinated set.

Imke de Pater note that she is also a member of the Europlanet coordination board and noted the strong showing of outer-planet related talks at that meeting in September.

It was noted that Tom Stallard had been particularly active in the New Horizons support promotion and in investigations of near-infrared auroral observations. His name was suggested as a rotating member.

Notes from individual disciplines:

Uranus and Neptune:

Heidi Hammel summarized the two Uranus at Equinox workshops. A summary of the first workshop on 2006 May 3-4 can be found at http://www.apl.ucl.ac.uk/iopw/uworkshop_060905.pdf

This workshop, in Pasadena, issued a statement: "Once every 24 years, we have an opportunity to see the planet Uranus and its moons from pole to pole, and to view its ring system edge on. That opportunity comes in 2007.

By observing the Uranus system at equinox in 2007, we will explore an atmosphere that is changing rapidly. We wil probe newly discovered faint rings. We will use the rare opporunity of mutual satellite eclipses to map the brightness variations on large moons.

Observations at the equinoxes of Jupiter, Saturn and pluto provided fundamental insights. The year 2007 is our chance to to the same for the Uranus sytem."

Ring-plane(equatorial) crossings will occur on 2007 May 2, Aug. 16 and 2007 Feb. 20. These singular events are probably more important for the rings and satellite investigations than for atmospheric investigations, which have already commenced, since most of the polar hemispheres are more-or-less accessible at the same time now.

Key measurements for the atmosphere include disk-resolved abundance variations, whole-disk abundance variations as a function of altitude and/or time. These would measure tropospheric temperatures, stratopsheric to thermospheric temperature profiles from stellar occultations, cloud/hazes from photmetric imaging, and zonal wind profiles at high northern latitudes from cloud tracking. Key measurements for the ionosphere focus on near-infrared H3+ auroral emission, and its short- and long-term evolution. For the rings, key measurement objectives include searches for structure of - and within - the rings, measurements of the phhysical and optical properties of ring material, and searches for faint outer rings and dust sheets. Satellites key measurements include a mixture of time-critical occultation events, moderately time-critical events for which particular phase angles are needed, and general observations of whole-disk properties, including composition and shapes.

A one-day workshop was held just before the DPS meeting to discuss atmospheric and ionospheric science during Uranus' 2007 equinox passage. The need for continued multi-wavelength imaging data was discussed, as well as the need for improved dynamical models of the atmosphere. Recent results were presented including:
- The first images at mid-IR (Orton et al. using the VLT) and millimeter (Hofstadter et al. using the SMA) wavelengths.
- A new analysis of vertical cloud structure based on IR spectroscopy from UKIRT (Irwin et al.).
- Improved CH4 and H2 opacity models (Sromovsky et al., Orton and Gustaffson).
- The discovery of a recently formed "dark spot" on Uranus, seen with Hubble (Sromovsky et al.).
- A tentative re-detection of Uranian aurorae from H3+ emission in the IR (Miller et al.).

Following up on this workshop, the Outer Planets Assessment Group (OPAG) issued a letter from their November meeting encouraging observatories to support observations of Uranus during equinox passage.

Augtin reported that the IOPW-Jupiter & Saturn Atmospheres discipline continues its effort to maintain the web page (http://www.ajax.ehu.es/pvol ) and database archive of (mostly) amateur images of both planets ("Planetary Virtual Observatory", PVOL). A link can also be found at the official web page: www.ehu.es/iopw/

These are some statistics for the site:
Image submissions since January 1, 2006:
Jupiter = 748 images (618 +130: PVOL-IOPW)
Saturn = 163 images (133 + 30: PVOL-IOPW)
Uranus = 31 images (19 + 12: PVOL-IOPW)
Neptune = 2 images (2 PVOL)
Contributions were received from observers in: Australia, France, Italy, Netherland, Philippines, Spain, and the US.
Telescope diameters ranged from 20 to 40/46 cm, and Webcams were used as detectors with a variety of visible filters. Most are uncalibrated images.
All these images can be sslected and downloaded using PVOL system.

A meeting of the discipline was held on the preceding evening, where the PVOL was demonstrated in its current form. Much of the disucssion was on the topic of observing the Oval BA and providing support for the New Horizons encounter. Chris Go, who "discovered" the color change, spoke about his work, mentioning that he thinks the color change from white to "red" took place over several months and wasn't even quite finished by April, 2006. John Westfal, of the American Lunar and Planetary Observers, the "official" U.S. amateur organization also spoke about the products that amateurs provide. This was the first time amateur astronomers had participated to such an active extent in the IOPW.

Henry Roe noted that ground-based support for Titan observations was continuing, but it involved a relatively small number of people.

Franck Marchis noted that interest in Io had been re-kindled with the potential opportunity for New Horizons to be getting some closer-up views during its flyby.

A general feeling that we might use the IOPW site link to laboratory measurements to serve as a user/lab scientist interface for what's needed by astronomers and space scientists. Among those discussed were lab measurements for ortho-para conversion. The May Uranus workshop also discussed several. The topic would be an imporant one for consideration by Phil. Crane's (NASA HQ-initiated) workshop on Planetary Atmospheres research, which was being delayed from his original request for the spring until another 6 - 12 months down the line.

Imke asked whether there might be some way to alert Telescope Allocation Committees and observatory directors on the Uranus ring plane crossing. Citation rates, which is what the University of California allocation committeed uses to judge how important earlier observations are, simply don't count for unique events. She did not want to spend time herself to check on citations and then relay that information/corrections to the NASA/ADS facility. If there is an easier way it may be worth doing.

Glenn Orton