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OCCULTATION OF TYC 1961-001236-1 BY 423 Diotima
2010 December 10
IOTA-ME


Five clearly observed positives were recorded in Iran for this event that crossed Africa and the Middle East.
Atila Poro was the team Leader and Dave Gault provided some long distance coaching.
All used visual timing with stopwatches or recorders.

View the updated prediction.

Observers:
  1    G Rostami,Taft (Yazd State), Iran
  2    G Poro,Sang bast Village,Mashhad,Iran   ( Time checked with GPS unit)
  3    G Salimi,Abravan Village,Mashhad,Iran   ( Time checked with GPS unit)
  4    G Ashkar,Fars, Shiraz, Iran
  5    G Lavari,Boshehr, Iran
  6(P) Prediction

Three other groups were in Saadat'shahr and Yazd and Boshehr.
They couldn't see the occultation because they had equipment problems, all of
them could find the star in less than 3 minutes (I'm sure).
For Shiraz observation, I think the occultation duration time is correct but for starting
occultation he registered is about 30 second before the occultation event!

For Mashhad groups, they set time with GPS and also checked it with other sources like radio
and internet.
When they observed occultation a person took movie and also record observers sounds.
After they observed the occultation they checked the time given by assistant and movie and sound.
This gives us more confidence in those times (sites 1 and 2).

  There were in fact several teams at each location and the results summarise these.

    

Diotima occultation - 2010 December 10

Discussion:

The circle above is plotted at the expected 172 km diameter of Diotima.
It is clear that the clocks used for timing are not closely calibrated to each other.
As noted above the chords 2 and 3 near Mashhad used a GPS for synchronisation and appear most consistent.

Adjusted view:

Diotima occultation - 2010 December 10

In this second version the times for chords 1,4,5 have been shifted
by -47, +16.5, -46 seconds to make the centre their observations agree with 2 and 3.
This makes chord 4 at Shiraz agree very well with 2 and 3 at Mashhad.
The other two chords seem short and are likely caused by lack of experience in looking for brightness changes.

The team are to be congratulated for an overall good result which shows
what can be done by a well organised team with visual obseravtion alone.
We look forward to many more succeses for the IOTA-ME team.

With 5 chords we can be confident that the path of Diotima and that it was
close to the predicted line.

For more information and team photos please refer to IOTA-ME site

Observational Data:

Observation details for MP (423) Diotima
By Star              TYC 1961-01236-1
On 2010-12-10  at 01:12:00.0

_______________________________

Observer   Group E - Farzad Ashkar
Location   Fars, Shiraz, Iran
Longitude   +52:29
Latitude   +29:35
Altitude   150 m
Datum      WGS84
Telescope Newtonian
Aperture   20 cm
Seeing     Steady Clear
Camera Type
Camera Delay
Timing     Stopwatch Visual, no PE applied
Disappearance  01:09:38.00
Reappearance   01:10:05.00
Comments:

_______________________________

Observer   Group A - Atila Poro
Location   Sang bast Village, Mashhad, Iran
Longitude   +59:45
Latitude   +35:59
Altitude   998 m
Datum      WGS84
Telescope Dobsonian
Aperture   cm
Seeing     Steady Clear
Camera Type
Camera Delay
Timing     Stopwatch Visual, no PE applied
Disappearance  01:12:22.64
Reappearance   01:12:48.60
Comments: Team 1: M.Hossein Tale Zadeh Lari (observer) ,
          S.Majid Ghasemi (recorder).
          Team 2: A.Hasan ali Zadeh haghighi (observer) ,
          Hossein Davari (recorder)
          Team 3: H. Alizadeh Koshki (observer),
          S. Mahmoud Hosseini (recorder).

_______________________________

Observer   Group B - Fatemeh Salimi
Location   Abravan Village, Mashhad, Iran
Longitude   +59:58
Latitude   +36:04
Altitude   998 m
Datum      WGS84
Telescope Newtonian
Aperture   cm
Seeing     Steady Clear
Camera Type
Camera Delay
Timing     Stopwatch Visual, no PE applied
Disappearance  01:12:25.24
Reappearance   01:12:52.00
Comments: Team 1: Mehdi Hashemi  (observer) ,
          Maryam Dehghan & Zahra Khakzadi  (recorders).
          Team 2: Ali Fatollah zadeh(observer) ,
          Fatemeh Salimi (recorder)
          Team 3: Ahmad Nezam (observer),
          Zeynab Momen Zadeh & Akram Farzaneh (recorders).

_______________________________

Observer   Group C - S.Ghasem Rostami
Location   Taft (Yazd State), Iran
Longitude   +54:13
Latitude   +31:44
Altitude   1531 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   20 cm
Seeing     Steady Clear
Camera Type
Camera Delay
Timing     Stopwatch Visual, no PE applied
Disappearance  01:11:32.00
Reappearance   01:11:43.00
Comments: Team: Ali Ommani (observer),
          Ali Ahmadi, Mehdi Karim Pour,
          Yaser Ashor'zadeh & S.G. Rostami (recorders).

_______________________________

Observer   Group D - A.Reza Lavari
Location   Boshehr, Iran
Longitude   +51:26
Latitude   +28:29
Altitude   150 m
Datum      WGS84
Telescope other - specify below
Aperture   15 cm
Seeing     Steady Clear
Camera Type
Camera Delay
Timing     Stopwatch Visual, no PE applied
Disappearance  01:10:22.00
Reappearance   01:10:37.26
Comments: Team: A.Reza Lavari (observer),
          Ahmad Nasiri, Nasir Darvish'vand & Yosef Lavari (recorders).

    

Return to 2010 occultation results



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