The Summer 2011 IOTA Conference was, as we always efficiently plan, built around an important opportunity requiring massive deployment of forces in the service of occultation astronomy. Arguably the most important opportunity ever, this time, as the asteroid (90) Antiope was to occult a bright, red giant star a day after the meeting ended. Antiope is one of the few known binary asteroids - two nearly equal brightness asteroids in a very close orbit. By precisely determining the profile and positioning, we would significantly improve the orbit parameters, aiding longer term studies of gravitational dynamics of a non-spherical system. Our data, combined with photometry inversion models, could also be used to make detailed surface topography models of the two orbiting asteroids. Also, with a dense net of tracks, we hoped to scan for satellite "rocks" too small to show in visual or radar observations. Stable orbits are not predicted to be possible for a 3-body system where the two main objects are significantly irregularly shaped. Discovering new satellites would be an important new finding. Also, since the star has a significant diameter as projected at Antiope's distance, gradual events were expected, and careful photometry would enable smaller scale irregularities on the surface to be evidenced. And finally, the star was suspected to be a close binary, and video GPS photometry would show this, enabling two tracks per observing station.

We secured Sierra College's planetarium, in Rocklin, CA northeast of Sacramento, for our meeting site - an excellent venue. Here is the meeting agenda, and this link contains all the powerpoint presentations. The attendees above are: (standing) Steve Preston, John Westfall, Tony George, Joe Garlitz, Derek Breit, Hank Sielski, David Dunham, Eberhard Bredner, Earl Wilson, Daniel Falla, Joan Dunham, Fracois Colas, Chuck Herold, and Dave Kenyon. Front row (kneeling): Lampert Levy, Ted Swift, Walt Morgan, Mark Vincent, Scotty Degenhardt, Frederic Vachier (almost occulted), Richard Nolthenius, and Derald Nye


Tony George - rockin' out? No, he's conversing with the EVO online conferencing participants, making sure the connections were good.

As last year, we use the EVO video system to enable conference participation from around the world. Some of the presentations were given remotely in this way.

Paul Maley gives a talk on funding for IOTA observing projects, and collaborations with other solar system astronomers


Derald Nye, my old friend from Tucson days long ago, and Joan Dunham share a smile. Derald built an impressive observatory and has contributed much to occultation astronomy

The Homer DaBoll Award this year goes to Scotty Degenhardt, who has pioneered the development and employment of mass numbers of low-cost optics and videorecording stations for asteroid occultations. Most of us were silently pulling for Scotty - who has worked very hard for occultation astronomy at great personal cost

Paul holds up an example of Scotty's "Mighty Mini"


Scotty and Ted confer

The Eudora event crossing Florida was an object lesson in changing deployment plans at the last minute due to weather etc - the subject of David Dunham's talk. The ground work finding these remote sites wasn't wasted though - Dunham was able to use many of these for the similarly path'ed Hertzsprung event a couple of weeks later.

Tony George gave a talk summarizing the discovery of new double stars via asteroid occultations

Paul Maley's very challenging trip to Kurdistan, Iraq to network with the new IOTA/Middle East section and collaborate on an asteroid occultation, included a visit to the ill-fated 3.5m telescope at Erbil; a casualty of war.

Video feedback, and wondering whether one should look at the EVO camera for the benefit of the remote viewers, or look at the real audience... made for some surreal moments, here for Walt.

Walt Morgan gave a detailed talk on the characteristics of the new IOTA GPS video time insertion unit

There are significant improvements over the commendable (but no longer available) Kiwi VTI.

Walt and Dave Kenyon discuss the new VTI


Like all good conferences, many of the interesting exchanges happen around dinner

I would miss the morning session on Sunday.I had another engagement - the Donner Lake Triathlon - where I was (perhaps) going to be on a relay team. Donner was just 40 miles up I-80 from Rocklin. Very convenient! Check out my Donner webpage here.

After the post-race activities, I returned to Rocklin in time for the afternoon sessions on the latest updates for the important (90) Antiope event the following night.

Scotty, Joe, Ted discuss hardware

The 10 inch "suitcase telescope" perfect for airline transport to distant, faint events. David was assured it was easy to assemble for the attendee's benefit, as John Broughton and Bruce Bergere delivered the EVO presentation on-line.

Walt and Dave Gault (via EVO) with more on the use of the IOTA VTI.

And finally, Dunham discussed the summer weather patterns in the Central Valley, and the latest satellite images (in the on-screen image, blue=cloud) and weather forecasts for the Antiope event. Stratus was expected to come in through the Carquinez Straits, and a weak cold front to be moving through the north end of the Valley. Observers might have to be nimble to avoid cloudout.

Walt, David, Paul, Joe, and Tony mull over the weather details. In the end, David, Scotty, and Paul especially, and many others, succeeded in securing 39 positive chords of the Antiope occultation.

The observed profile of Antiope. No tertiary satellites were found - consistent with expectations.

Any corrections to the names above would be welcome. I enjoyed the get-together with old friends and new, and appreciate the efforts of so many in advancing the state of occultation astronomy and the improving the prospects for more high-precision observation sets, and collaborations with solar system astronomers.