In addition, observers from the Observatorire de Paris-Meudon travelled to New Zealand, and several amateur astronomers also captured the event. (Please advise me if I have left anyone out of the details below).

AAT - NSW, Australia (SWRI): Richard French & Kevin Shoemaker

A beautiful lightcurve showing significant atmospheric structure was obtained. A preliminary look at the data suggests that it may have the highest signal to noise ratio of any lightcurve so far obtained from any Pluto occultation. The AAT data contains features probably indicative of layers of different density within Pluto's atmosphere. It also features a substantial plateau (caused by extinction of the star's light in Pluto's atmosphere, rather than by the planet itself occulting the star) and a couple of intriguing departures from the expected flat bottom to the plateau. The fact that the AAT got such a lengthy occultation by the planet, combined with the Wellington data (see below) indicates that they were likely slightly north of the central line. The AAT data shows that the event occurred about 3 minutes later than predicted.

Carter Observatory - Wellington, NZ (SWRI): Marc Buie & Trina Ruhland

The Carter Observatory's 41cm reflector was used to observe through quite thick cloud. However an occultation by Pluto's atmosphere alone was captured (exactly 18 years and 3 days after the same instrument had obtained a similar result at the first observed Pluto occultation in 1988). The night started poorly but went from wet and total overcast at 0630 UT to completely clear by 1000. The field was found without trouble with event time expected about 1620. By 1515 wisps of cloud had started to build up in the west and between then and 1620 the cloud increased rapidly and went through phases from fluffy clumps to thick cirrus. Data was acquired through the event window and the combined star/Pluto image was visible much of the time. In spite of the apparently poor quality of the data, differential photometry of the star/planet relative to field stars shows a dip of about 25% at a time consistent with the AAT data. The Carter Observatory and AAT data alone provide a constraint on the current extent of Pluto's atmosphere.

Wanaka - Otago, NZ (SWRI): Leslie Young, Cathy Olkin & Ross Dickie

The SWRI portable Meade 14 taken to Otago was first set up at Lauder under a clear sky. However during early evening mist came in then it started to snow. The observers packed up the telescope and drove to Wanaka but interference from cloud/snow probably means that they have no useful data.

Launceston, Tasmania (SWRI): Eliot Young & Jeff Register

The second SWRI portable Meade 14 in Tasmania observed in clear conditions but experienced problems with frost and condensation on the scope. Removing the CCD camera from the scope after the event the observers found condensation on the CCD window. It will probably be some time before they can determine whether they captured an event. However the Carter Observatory data suggests that Launceston should have seen a slightly deeper atmospheric occultation than did Carter.

Hobart, Tasmania (MIT-Williams): Steven Souza & Anne Jaskot

Data was obtained with the 1-m telescope of the University of Tasmania at Hobart. Calibration on stars in the field allowed the effects of clouds to be removed, giving an excellent light curve showing the occultation.

Tasmania: Shevill Mathers, Wolfgang Beisker, Alain Dorissounderin (Paris) & Stefan Dieters (UTAS)

Data was obtained by Wolfgang Biesker and Shevill Mathers using the UTAS 16" telescope at Mt Canopus. Alain Dorissounderin and Stefan Dieters observed with a C14, upon which a lot of work was done to get it ready for the event. This instrument was located in an observatory adjacent to the Canopus 16".

Mt Stromlo, ACT (MIT-Williams): Amanda Gulbis & Emily Kramer

A substantial dip lasting almost two minutes was recorded using the experimental EOS 2-m telescope at Mt. Stromlo.

Siding Spring, NSW (MIT-Williams): Elisabeth Adams, Paul Francis & Robert Lucas

Similar data to the above was obtained using the 2.3-m telescope at Siding Spring.

Black Springs, SA (MIT-Williams): Joseph Gangestad, Michael Person, Ian Bedford, Lynton Hemer,& Fraser Farrell

The 0.75m Newtonian of Ian Bedford was used and recorded data. Fraser Farrell reports that: "...the lightcurve shows a very nice ingress-totality-egress event. Both the [Black Springs and Stockport] sites experienced a clear and frosty night. I recall that Black Springs had no cloud at all on the field until well after the event. There was the occasional bit of cloud noticed in the direction of Stockport but I don't think Blair's observations were affected either. Moonlight was a problem at both sites."

Stockport, SA: Blair Lade

The 50 cm Newtonian-Cassegrain of the Astronomical Society of South Australia was used in conjunction with a modified (cooled) Meade DSI Pro b/w camera on 1 second integrations, obtaining an image about every 2 seconds for around 3 hours, centered about the event. A very nice lightcurve has been extracted from the data. Fraser Farrell further reports: "Blair's preliminary analysis of the central few minutes shows an ingress lasting ~15 seconds, followed by a minimum lasting ~78 seconds, and concluded by a ~15 seconds egress. Magnitude drop of ~0.35 (unfiltered CCD) according to MaximDL. This implies an approximately 1840km chord across Pluto itself, plus about 350km of chord through Pluto's atmosphere on each side. So if Pluto is indeed a 2300km diameter sphere, then Stockport was about 690km off centreline. And Pluto's detectable atmosphere was about 200km thick. Blair and I will continue to work on all of his several GB of images to see if there's any signals from rings, moonlets etc."

Mt John Observatory, Lake Tekapo, NZ (MIT-Williams/Paris): Jay Pasachoff, Bryce Babcock, David Ramm, Bruno Sicardy, Thomas Widemann

The 1-metre telescope had been booked by Pasachoff, Babcock and Ramm (Williams College/University of Canterbury) with Sicardy and Widemann (Paris) on one of the 0.61m scopes. However no data was obtained - in spite of it being clear at the time of the event - because of a power cut which affected much of the South Canterbury region. The loss of power was a result of exceedingly heavy snowfalls which also made all roads in and out of the Mackenzie country impassable for more than three days. After a couple of days the Observatory was visited by a civil defence helicopter which found everyone in good spirits and happy to remain on-site until road access was restored.

A description of Jay Pasachoff's experiences at Mt John can be found here.

Hawkesbury Heights, NSW: Dave Gault

Dave Gault observed in the clear over the occultation period using a Meade Deep Sky Imager Pro. He recorded an event which appears to include an atmospheric decline and a (relatively noisy) central plateau which may be consistent with the AAT data.

Reedy Creek, QLD: John Broughton

John Broughton obtained 98 15-second sub-frame CCD exposures between 15:53:02 and 16:29:38 UT (when cloud interfered). This covers the period of any occultation by Pluto and the P2 satellite, except for 7.5 seconds of dead time between exposures. John was well inside the occultation band and north of the AAT.

Auckland Observatory, Auckland, NZ: Grant Christie & Tim Natusch

The Auckland Observatory's 50cm Zeiss was used but conditions were far from ideal with occasional clear patches interspersed with thick cloud and showers. It was raining only a few minutes before the event but did clear, although the target star then needed to be reacquired. Data was then taken but it is as yet unclear whether data was taken over the exact event period. The Carter Observatory data confirms that Auckland was well inside the band of occultation by Pluto's atmosphere.

Farm Cove Observatory, Auckland, NZ: Jeannie McCormack

Problems with weather meant that observing could not be started until 1629 UT, after the time of the event indicated by the AAT data. Monitoring was carried out until 1700.

Coonabarabran, NSW: Kevin Cooper

The occultation by Pluto was captured using an ST-8, but the time resolution was only about 1 minute per frame.

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