IOTA-ES : Call for Observations

Station Map for the Occultation by (657) Gunlod at Friday, 2009 January 02 (~ 23:29 UT)

V-Magnitude of target star TYC 2403-00016-1: 11.4 mag
Johnson B-V Colour Index: + 0.5
The UCAC2 gives a “pseudo-R magnitude” of 11.3 mag

The max duration is expected to be 3.5 sec with a max drop of 3.3 mag.
The event will take place at an altitude of 62 deg and at azimuth 224 deg. The sun will be at an altitude of -59 deg. (At predicted centre line for longitude E 10 deg)

There is a 1 sigma uncertainty interval of  ±  0.85 path widths.
The probabilities to see a positive event:

Centre line: ~  44 %
Path limits: ~  38 %
1 sigma lines:  ~ 14 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2009_01/0102_657_17126.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20090102_17126_Sites.txt

Map and Coordinates at the web page of  E.A.O.N.
http://astrosurf.com/eaon/Occultations%20January.htm

Good luck with your observation!

Oliver Klös

IOTA-ES

Station Map for the Occultation by (1758) Naantali at Friday, 2009 January 02 (~ 19:48 UT)

V-Magnitude of target star TYC 1337-01443-1: 10.3 mag
Johnson B-V Colour Index: + 0.9
The UCAC2 gives a “pseudo-R magnitude” of 9.9 mag

The max duration is expected to be 2.1 sec with a max drop of 4.9 mag.
The event will take place at an altitude of 36 deg and at azimuth 95 deg. The sun will be at an altitude of -34 deg. (At predicted centre line for longitude 0 deg)

There is a 1 sigma uncertainty interval of  ±  1.90 path widths.
The probabilities to see a positive event:

Centre line: ~ 21 %
Path limits: ~  20 %
1 sigma lines:  ~ 10 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2009_01/0102_1758_18837.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20090102_18837_Sites.txt

Map and Coordinates at the web page of  E.A.O.N.
http://astrosurf.com/eaon/Occultations%20January.htm

Good luck with your observation!

Oliver Klös

IOTA-ES

Station Map for the Occultation by (743) Eugenisis at Wednesday, 2008 December 31 (~ 19:06 UT)

V-Magnitude of target star TYC 5777-00050-1: 10.2 mag
Spectral type: G0
Johnson B-V Colour Index: + 0.6
The UCAC2 gives a “pseudo-R magnitude” of  10.2 mag

The max duration is expected to be 1.2 sec with a max drop of 5.5 mag.
The event will take place at an altitude of 10 deg and at azimuth 245 deg. The sun will be at an altitude of -27 deg. (At predicted centre line for longitude 0 deg)

There is a 1 sigma uncertainty interval of  ±  1.11 path widths.
The probabilities to see a positive event:

Centre line: ~ 35 %
Path limits: ~  32 %
1 sigma lines:  ~ 13 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1231_743_14024.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081231_14024_Sites.txt

Good luck with your observation and “clear skies” for 2009!!

Oliver Klös

IOTA-ES

Station Map for the Occultation by (29) Amphitrite at Wednesday, 2008 December 31 (~ 05:05 UT)

Magnitude of target star 2UCAC 31689676: 11.8 mag

The max duration is expected to be 15.3 sec with a max drop of 0.34 mag only.
The event will take place at an altitude of 46 deg and at azimuth 167 deg. The sun will be at an altitude of -26 deg. (At predicted centre line for longitude 0 deg)

There is a 1 sigma uncertainty interval of  ±  0.25 path widths.
The probabilities to see a positive event:

Centre line: ~ 96 %
Path limits: ~  50 %
1 sigma lines:  ~ 16 %
2 sigma lines: ~ 2 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1231_29_13442.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081231_13442_Sites.txt

Good luck with your observation,

Oliver Klös

IOTA-ES

Station Map for the Occultation by (29943) 1999 JZ78 at Wednesday, 2008 December 31 (~ 00:20 UT)

V-Magnitude of target star TYC 1906-00192-1: 9.8 mag
Johnson B-V Colour Index: + 0.4
The UCAC2 gives a “pseudo-R magnitude” of  9.7 mag

The max duration is expected to be 2.0 sec with a max drop of 4.1 mag.
The event will take place at an altitude of 74 deg and at azimuth 204 deg. The sun will be at an altitude of -69 deg. (At predicted centre line for longitude E 05 deg)

There is a 1 sigma uncertainty interval of  ±  4.48 path widths.
The probabilities to see a positive event:

Centre line: ~ 9 %
Path limits: ~  9 %
1 sigma lines:  ~ 5 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1231_29943_15069.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081231_15069_Sites.txt

Map and Coordinates at the web page of  E.A.O.N. (not updated with Steve Preston’s latest data):
http://astrosurf.com/eaon/Occultations%20December.htm

Good luck with your observation,

Oliver Klös

IOTA-ES

Station Map for the Occultation by (105) Atemis at Tuesday, 2008 December 30 (~19:12 UT)

Magnitude of target star 2UCAC 28151691: 12.0 mag

The max duration is expected to be 8.7 sec with a max drop of 1.2 mag.
The event will take place at an altitude of 14 deg and at azimuth 124 deg. The sun will be at an altitude of -42 deg. (At predicted centre line for longitude E 20 deg)

There is a 1 sigma uncertainty interval of  ±  1.06 path widths.
The probabilities to see a positive event:

Centre line: ~  36 %
Path limits: ~  33 %
1 sigma lines:  ~ 13 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1230_105_13441.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081230_13441_Sites.txt

Map and Coordinates at the web page of  E.A.O.N. (not updated with Steve Preston’s latest data):
http://astrosurf.com/eaon/Occultations%20December.htm

Good luck with your observation,

Oliver Klös

IOTA-ES

Station Map for the Occultation by (506) Marion at Tuesday, 2008 December 30 (~ 01:04 UT)

V-Magnitude of target star TYC 0835-00953-1: 11.5 mag
Johnson B-V Colour Index: + 0.3
The UCAC2 gives a “pseudo-R magnitude” of  11.3 mag

The max duration is expected to be 17.3 sec with a max drop of 1.9 mag.
The event will take place at an altitude of 58 deg and at azimuth 164 deg. The sun will be at an altitude of -50 deg. (At predicted centre line for longitude E 25 deg)

There is a 1 sigma uncertainty interval of  ±  0.48 path widths.
The probabilities to see a positive event:

Centre line: ~ 70 %
Path limits: ~  48 %
1 sigma lines:  ~ 16 %
2 sigma lines: ~ 2 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1230_506_13439.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081230_13439_Sites.txt

Map and Coordinates at the web page of  E.A.O.N. (not updated with Steve Preston’s latest data):
http://astrosurf.com/eaon/Occultations%20December.htm

Good luck with your observation,

Oliver Klös

IOTA-ES

Station Map for the Occultation by (9) Metis at Monday, 2008 December 29 (~ 22:53 UT)

Good Test for Video Equipment

V-Magnitude of target star TYC 0637-00036-1: 12.0 mag
Johnson B-V Colour Index: + 1.3
The UCAC2 gives a “pseudo-R magnitude” of  11.8 mag

Please notice:

The combined light of star and asteroid will be ~ 9.8 mag (the magnitude of the asteroid) during an occultation!

“Occult Watcher” indicates (9) Metis as suspected binary asteroid!

The max duration is expected to be 35.5 sec with a max drop of 0.13 mag only.

David Dunham (IOTA) wrote about this small drop in magnitude:

“This occultation by a large asteroid and a fainter star provides a good test of video equipment, to see what can be recorded, preferably from several sites so that the consistency of results can be assessed from a fit of the observed chords. Metis’ mag. will be 9.8 while that of the star is only 12.0, producing a magnitude drop of 0.13 (or 0.16 in red).

Tony George recorded a similar event in 2006 (see below), but nobody else recorded it. We are trying to see how small the mag. Drop can be and still obtain reliable results from video, so this Dec. 29th event is a good opportunity for that. Recently, a few IOTA observers in the southern USA recorded an occultation of a faint star by (4) Vesta with a mag. drop predicted to be only 0.01, and Limovie analysis failed to find the occultation in any of the recordings; that small a drop is too small for our video equipment to reliably detect. Other events with mag. drops of 0.2 have been successfully recorded with video equipment in the USA.”

Tony George about his experience and the event at Dec 29:

“I successfully observed an occultation by Metis in 2-13-2006. It was video recorded. I defocused the target star to make sure pixels were not saturated. The mag drop was 0.12, similar to this event. The SNR was 0.64, relatively low, but the event is clearly visible in the data. This would be a good one for multiple chords.”

The event will take place at an altitude of 30 deg and at azimuth 251 deg. The sun will be at an altitude of -60 deg. (At predicted centre line for longitude E 10 deg)

There is a 1 sigma uncertainty interval of  ±  0.15 path widths.
The probabilities to see a positive event:

Centre line: ~ 100 %
Path limits: ~  50 %
1 sigma lines:  ~16 %
2 sigma lines: ~ 2 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1229_9_13438.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081229_13438_Sites.txt

Good luck with your observation,

Oliver Klös

IOTA-ES

Station Map for the Occultation by (1135) Colchis at Monday, 2008 December 29 (~ 20:57 UT)

V-Magnitude of target star 2UCAC 42390990: 12.6 mag

The max duration is expected to be 4.1 sec with a max drop of 1.5 mag.
The event will take place at an altitude of 57 deg and at azimuth 114 deg. The sun will be at an altitude of -51 deg. (At predicted centre line for longitude E 10 deg)

There is a 1 sigma uncertainty interval of  ±  1.73 path widths.
The probabilities to see a positive event:

Centre line: ~ 23 %
Path limits: ~  22 %
1 sigma lines:  ~10 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1229_1135_19730.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081229_19730_Sites.txt

Map and Coordinates at the web page of  E.A.O.N. (not updated with Steve Preston’s latest data):
http://astrosurf.com/eaon/Occultations%20December.htm

Good luck with your observation,

Oliver Klös

IOTA-ES

Station Map for the Occultation by (829) Academia at Monday, 2008 December 29 (~ 05:40 UT)

V-Magnitude of target star TYC 2447-00820-1: 12.1 mag
Johnson B-V Colour Index: + 0.3
The UCAC2 gives a “pseudo-R magnitude” of  12.1 mag

The max duration is expected to be 4.0 sec with a max drop of 2.0 mag.
The event will take place at an altitude of 26 deg and at azimuth 297 deg. The sun will be at an altitude of -16 deg. (At predicted centre line for longitude E 05 deg)

There is a 1 sigma uncertainty interval of  ±  0.81 path widths.
The probabilities to see a positive event:

Centre line: ~ 46 %
Path limits: ~  39 %
1 sigma lines:  ~15 %
2 sigma lines: ~ 1 %

(Calculation according to Raymond Dusser, E.A.O.N. Circular #10)

PLEASE REMEMBER: Predictions are sometimes wrong. Please observe even with a small probability.
Let other observers know about you observing plans: Announce you station with OccultWatcher !

More information (coordinates, finder charts) at Steve Preston’s prediction:
http://asteroidoccultation.com/2008_12/1229_829_13436.htm

Table of potential observing stations and cities with distance from center of predicted path (Derek C. Breit):
http://www.poyntsource.com/New/Google/20081229_13436_Sites.txt

Map and Coordinates at the web page of  E.A.O.N. (not updated with Steve Preston’s latest data):
http://astrosurf.com/eaon/Occultations%20December.htm

Good luck with your observation,

Oliver Klös

IOTA-ES