THE LUNAR ECLIPSE OBSERVER

1996 SEPTEMBER 27 ECLIPSE CRATER TIMING OBSERVATIONS

1996 SEPTEMBER 27 TOTAL LUNAR ECLIPSE CRATER TIMING OBSERVATIONS

 

A new web page from the CALWELL LUNAR OBSERVATORY

Amended 1996 December 21

 

Prepared by

Byron W. Soulsby, 23 Andrew Crescent, Calwell, Australian Capital Territory, 2905 Australia.

e-mail minnah@netspeed.com.au

 

Picture 1 KbCALWELL LUNAR OBSERVATORY

Longitude 149 o 06 ' 00.9 "(E), Latitude -35 o 26 ' 31.4"(S), Elevation 630m.

The observatory logo above is a thumbnail of my first CCD image analysed from the 1990 February 9 eclipse.

 

This page provides data from the analysis of many crater timing observations made throughout the world for the total lunar eclipse of 1996 September 27. To date fourteen astronomers have submitted their observations for reduction. However, several potential observers were disappointed as their local weather conditions were poor, but some were able to view the eclipse live. See my page concerning the analysis of real time images at :

click for the analysis of real time images from the 1996 September 27 total lunar eclipse.

The eclipse circumstances described below, were provided to help observers plan their activities, and the times predicted can be compared with the actual observations in the summary of data and full reduction tables for each of the astronomers.

Here, the enlargement of the umbra, due to refraction of light from the Sun through the atmosphere of the Earth is revealed by the crater timings, as well as the shape of the umbral shadow. This shape is again proven to be elliptical of the order of 3 times that expected. One observer's data for this eclipse (see Figure 1 below) shows an observed out-of-round shape of the umbra of 1 in 63, which is in fact, around 3.4 times greater than that expected by the estimated geometry for this particular eclipse.

PRIME CONTACT TIMES FOR LUNAR ECLIPSE OF 1996 September 27

 

LUNAR ECLIPSE CIRCUMSTANCES

 

Figure 18 Kb

Figure 1: TOTAL LUNAR ECLIPSE 1996 SEPTEMBER 27.

 

PRIME CONTACT TIMES in U.T.

 

Moon enters penumbra 0h 12m 29s

Moon enters umbra (1C) 1h 12m 26s

Total Eclipse begins (2C) 2h 19m 20s

Middle of Eclipse 2h 54m 25s,

Total Eclipse ends (3C) 3h 29m 30s

Moon leaves umbra (4C) 4h 36m 24s

Moon leaves penumbra 5h 36m 21s

The eclipse Magnitude was 1.245

NOTE: As explained for the predictions for the eclipse of 1996 April 3-4, due to effect of umbral oblateness the 1996 September 27 FIRST CONTACT should be at 1h 12m 28s, (or 2 seconds later than that listed above), SECOND CONTACT at 2h 19m 38s (or 18 seconds later), THIRD CONTACT at 3h 28m 52s (or 38 seconds earlier) and FOURTH CONTACT at 4h 36m 13 (or 11 seconds earlier).

 

SUMMARIES OF CRATER TIMING OBSERVATIONS

click for the analysis of individual observers' crater timing reductions for the 1996 September 27 total lunar eclipse.

For an explanation of the terms used in these tables please refer to the nomenclature listed below and also listed on my other web pages.

ANALYSIS OF LUNAR ECLIPSE OBSERVATIONS

- BY BYRON W. SOULSBY, CALWELL LUNAR OBSERVATORY, AUSTRALIA

**** T A B L E 2 ****

STATISTICAL ACCEPTANCE USED IS 0 < %E < 4

CRATER TIMING REDUCTIONS FOR 1996 SEPTEMBER 27

 

IMMERSIONS EMERSIONS

 

OBSERVER

 

NUMBER

MEAN

%E

MEAN ERROR

NUMBER

MEAN

%E

MEAN ERROR







ROBERTSON, TIM




8

2.5952

0.3883

CASTANO, JOSE GOMEZ

29

2.0710

0.0781

5

1.7110

0.3749

BINDER, DR.LOUIS

2

1.2503

0.5540




GONCALVES, RUI

28

1.9363

0.1209

28

1.8358

0.1460

BARONI, SANDRO

14

1.8666

0.0330

8

1.9303

0.0275

GARCIA, ANTONIO




8

2.6999

0.2543

ZYL, KOOS VAN

7

2.1481

0.4194

1

1.4214

-

RAPAVA, DANIELA

22

2.8132

0.1007

1

0.5317

-

KEREKESOVA

17

2.5719

0.1350




AMBROZ

5

2.0829

0.1325




SANTOS, GERALDO

8

2.8395

0.0823




RIPERO, JOSE

11

2.1478

0.1177

13

2.2299

0.1535

SANTOS, JOAO RICARDO O

19

2.8842

0.1658

12

1.2552

0.1659

ZIBORDI, LUIZ FERNANDO

8

1.4205

0.1545

11

2.3090

0.2441

OVERALL MEAN %E FOR 170 IMMERSIONS IS 2.2734 +/- 0.1274 %

 

OVERALL MEAN %E FOR 95 EMERSIONS IS 1.9912 +/- 0.1921 %

 

TOTAL NUMBER OF OBSERVERS: 14, TOTAL NUMBER OF TIMINGS: 265

 

VALUES OF F & FM ARE 298.26, 218.863

DATE: 12-21-1996 AT TIME 15:25:55

 

 

Nomenclature used:

where OBSERVER is the astronomer conducting the crater timing observations,

IMMERSIONS where the craters timed are immersed into the umbra,

EMERSIONS where the craters timed have emerged from the umbra,

NUMBER of crater timings providing an %E within the range 0 < %E < 4,

MEAN %E, the computed umbral enlargement =

radii (theoretical - observed) * 100 % / theoretical radius.

MEAN ERROR is the error of the mean = standard deviation /SQRT(NUMBER).

 

The computations were made using MicroSoft™ QuickBASIC computer codes prepared by the author.

OBLATENESS ESTIMATES FOR 1996 SEPTEMBER 27

STATISTICAL RANGE USED 0 < E% < 4

OBSERVER

TYPE

No

Ecc

Re

Rp

Fo

SD

SK'









CASTANO, JOSE GOMEZ









IM

O

29.00

0.1759

0.7632

0.7513

64.1333

0.0459

3.4126

IM

T

29.00

0.0922

0.7383

0.7352

234.8081

0.0232

0.9321

EM

O

5.00

0.3249

0.7699

0.7281

18.4322

0.0079

11.8739

EM

T

5.00

0.1171

0.7403

0.7352

145.4591

0.0760

1.5046

GONCALVES, RUI









IM

O

28.00

0.1850

0.7633

0.7501

57.9487

0.0420

3.7768

IM

T

28.00

0.0978

0.7387

0.7352

208.5097

0.0217

1.0497

EM

O

28.00

0.1072

0.7527

0.7483

173.3893

0.0642

1.2623

EM

T

28.00

0.0897

0.7371

0.7341

248.1765

0.0523

0.8819

BARONI, SANDRO









IM

O

14.00

0.0553

0.7498

0.7487

-

0.0140

0.3350

IM

T

14.00

0.1017

0.7390

0.7352

192.8449

0.0250

1.1349

EM

O

8.00

0.1232

0.7557

0.7500

131.2786

0.0893

1.6672

EM

T

8.00

0.0946

0.7376

0.7343

222.9703

0.0660

0.9816

RAPAVA, DANIELA









IM

O

25.00

0.1428

0.7638

0.7560

97.6193

0.0281

2.2420

IM

T

25.00

0.0907

0.7381

0.7351

242.4865

0.0173

0.9026

KEREKESOVA









IM

O

19.00

0.0894

0.7568

0.7538

249.5250

0.0188

0.8771

IM

T

19.00

0.0875

0.7379

0.7351

260.6703

0.0184

0.8396

AMBROZ









IM

O

5.00

0.2149

0.7666

0.7487

42.7935

0.0031

5.1144

IM

T

5.00

0.0873

0.7379

0.7351

261.7988

0.0249

0.8360

RIPERO, JOSE









IM

O

11.00

0.2657

0.7822

0.7541

27.8200

0.0845

7.8671

IM

T

11.00

0.1015

0.7392

0.7353

193.6282

0.0311

1.1303

EM

O

13.00

0.1594

0.7643

0.7545

78.2254

0.1086

2.7979

EM

T

13.00

0.0895

0.7370

0.7341

249.3052

0.0585

0.8779

VALUE OF FM (RECIPROCAL) = 218.86

 

DATE OF RUN 11-24-1996 AT TIME 16:49:55.

 

 

Nomenclature in the table above:

TYPE is IM = Immersions, or EM = Emersions, No = Number of timings, Ecc = Eccentricity of umbra, Re = Radius at umbral equator, Rp = Radius at umbral pole, Fo = reciprocal oblateness, SD = standard deviation of data, SK' = oblateness ratio when compared with the expected oblateness (Fm) due to Meeus.

Picture 21 Kb

Figure 1: Best fit linear analysis of the observations by

Jose Gomez Castano showing the observed oblateness of the umbra as 1/63.

Occultations during the 1996 September 27 eclipse

 

Stellar occultation predictions were produced using Dave Herald's program Occult.exe Version 2.0. and were given for selected sites in the Supplement:

* Occultations for the 1996 Lunar Eclipses

 

 

Please forward your site details and occultation observation details to me by e-mail: minnah@netspeed.com.au

* A full analysis of observations of the 1996 April 3-4 eclipse

 

* A progressive analysis of real time images and video observations of the 1996 September 27 eclipse

 

* About the Lunar Eclipse Observer

* Return to Lunar Eclipse Observer Home Page