The Venus Transit 2004 European Science & Technology Week 2004 Visit the websites of the VT-2004 organisers

The Venus Transit 2004

... Photos by Themes

The "Black Drop" Phenomenon

The 'Black Drop' phenomenon

On this page, photos related to the so-called "Black Drop" phenomenon are displayed, as they were recorded during the Venus transit on June 8, 2004 and shown at the VT-2004 website. This effect is illustrated on the drawing to the left and has been known by observers since long. It implies that Venus appears to be "stuck" to the limb of the Sun near the moments of the second and third contacts, as if with some kind of chewing-gum. It makes it difficult to estimate the moment when the border of Venus' dark circle exactly touches the border of the Sun.

Details about this phenomenon were placed on a dedicated webpage, warning all observers to be careful when timing the contacts. However, the experience during this year's transit proved that it must have been mostly due to the lesser optical quality of the telescopes that were used to observe the transits in the XVIII and XIXth centuries.

In any case, as the photos on this page demonstrate, the "Black Drop" phenomenon obviously did not play any significant role this time. Many observers remarked that they did not suffer any particular difficulties with the timing and many image sequences (see below) testify to the general absence of such an effect. Look also at the special page in the VT-2004 Photo Archive that deals with image processing techniques on photos obtained near the moments of the contacts.

An overview of the VT-2004 Photo Archive is available and a number of these photos have been elected "VT 2004 Photo of the Day".

All photos on this page may be downloaded and used, provided the photographers (authors) and the VT-2004 programme are indicated as source.


Individual Photos Displaying the Varying Degrees of the "Black Drop" Effect

Venus Transit - 2nd Contact

Venus Transit - 2nd Contact

[640 x 480 pix - 92

Andjelko Glivar
Celestron 102mm f/5 with 2x teleconverter
Canon EOS 300D digital SLR camera
[Black Drop?]
More images at this site
June 8, 2004
Croatia

Venus Transit - 2nd Contact

Venus Transit - 2nd Contact

[2900 x 1946 pix - 161k]

Paolo Campai
[Black Drop phenomenon visible]
June 8, 2004, 07:39:50 UT
Florence, Italy

Venus Transit - Second Contact

Venus Transit - Second Contact

[384 x 288 pix - 47k]

Frederik Bove
10-inch Meade LX200
Mintron MTV-12v1
June 8, 2004
Belgium

Venus Transit (Black Drop)

Venus Transit (Black Drop)

[604 x 564 pix - 25k]

Statis Kalyvas
4.5-inch Mizar telescope
Nikon Coolpix 750
June 8, 2004
Thessaloniki, Greece

Near 2nd Contact

Near 2nd Contact

[800 x 640 pix - 38k]

VT-2004 Team
Slovak Union of Amateur Astronomers
Observatory Rimavska Subota
160/2450mm refractor with AstroSolar filter
CCD camera SHT
June 8, 2004, 05:39:50 UT
Rimavska Subota, Slovakia
More images at this site

Venus Transit - Second Contact

Venus Transit - Third Contact

[384 x 288 pix - 50k]

Frederik Bove
10-inch Meade LX200
Mintron MTV-12v1
June 8, 2004
Belgium

Venus at 3rd Contact (3)

Venus at 3rd Contact (3)

[320 x 240 pix - 42k]

Daniel del Valle
8-inch Schmidt-Cassegrain telescope
Logitech QuickCam
["Black Drop" phenomenon] June 8, 2004, 11:10 UT
Aguadilla, Puerto Rico, USA

Near Third Contact

Near Third Contact

[640 x 480 pix - 16k]

Saverio Cammarata & Giuseppe Marino
Gruppo Astrofili Catanesi
Webcam Philips Toucam Pro and Schmidt-Cassegrain 25 cm telescope.
Median of 40 frames.
June 8, 2004
Catanese, Italy

Third Contact

Third Contact

[800 x 640 pix - 18k]

VT-2004 Team
Slovak Union of Amateur Astronomers
Observatory Rimavska Subota
160/2450mm refractor with AstroSolar filter
CCD camera SHT
June 8, 2004, 11:03:40 UT
Rimavska Subota, Slovakia
More images at this site

 

Photo Sequences Near Second Contact

Venus Transit - The Beginning

Venus Transit - The Beginning

[512 x 1024 pix - 22k]

Robert Fosbury
ST/ECF - ESO HQ
3-inch refractor
Sony DSC-F717
June 8, 2004
Ottobrunn near Munich, Germany

Venus Transit (Ingress)

Venus Transit (Ingress)

[1300 x 975 pix - 110k]

Elio Daniele
Gruppo Astrofili O.R.S.A.
Apochrom. refractor Tele Vue NP101
550mm - f/5.4 with AstroSolar filter
Nicon D100 Camera
June 8, 2004
Palermo, Italy

Venus Transit (Composite)

Venus Transit (Composite)

[900 x 823 pix - 197k]

Domenico Licchelli
Osservatorio del Fiorini
Apo 75mm f/6.7 with 3 x Barlow
TouCam Pro
Exposure 1/250 and 1/1500 sec
[Very poor seeing]
May 20, 2004, 05:34:06 - 11:12:06 UT
Lecce, Italy

 

Photo Sequences Near Third Contact

The Black Drop and Optical Resolution

The Black Drop and Optical Resolution

[406 x 606 pix - 77k]

Herbert Raab
Linzer Astronomische Gesellschaft
100-mm f/9 flourite refractor
Solar Max 60 H-alpha filter
Mintron 12V1C-EX B/W video camera
[Images from the video sequence obtained at nearly the same moment, but with "bad" (left) and "good" (right) image sharpness are compared. It is clear that the "black drop" phenomenon is more pronounced in the "bad" images.]
More images at this site
June 8, 2004, 11:03 UT
Linz, Austria

Third Contact at High Resolution

Third Contact at High Resolution

[1500 x 554 pix - 73k]

Ralf Vandebergh
6-inch refractor f/8
Sony TRV740 camcorder
[All images are composites of several frames]
June 8, 2004, 11:00 - 11:05 UT
The Netherlands

Black Drop Development

Black Drop Development

[408 x 1006 pix - 173k]

Eric Walker
Highlands Astronomical Society
114-mm reflector with 32-mm Plossl
Nikon Coolpix 5700
June 8, 2004, 11:03:04 - 11:07:11 UT
Culloden Moor near Inverness, Scotland, UK

Venus Exit

Venus Exit

[1200 x 960 - 106k]

Elio Daniele & Salvo Careri
Refractor Tele Vue NP101 550mm f5.4
Nikon D100, Astrosolar Filter
June 8, 2004
Palermo, Italy
Astronomy Club O.R.S.A.

Black Drop Effect

Black Drop Effect

[503 x 1300 pix - 41k]

Mauro Auteri & Floriano Paglia
G.V. Schiaparelli Astronomical Observatory, Varese, Italy
SC 203mmm at f/10 + Webcam Toucam Pro. June 8, 2004 ; 11:02-11:04 UT

Venus Transit (Egress)

Venus Transit (Egress)

[1300 x 975 pix - 100k]

Elio Daniele
Gruppo Astrofili O.R.S.A.
Apochrom. refractor Tele Vue NP101
550mm - f/5.4 with AstroSolar filter
Nicon D100 Camera
June 8, 2004
Palermo, Italy

Venus Transit (Composite)

Venus Transit (Composite)

[900 x 823 pix - 197k]

Domenico Licchelli
Osservatorio del Fiorini
Apo 75mm f/6.7 with 3 x Barlow
TouCam Pro
Exposure 1/250 and 1/1500 sec
[Very poor seeing]
May 20, 2004, 05:34:06 - 11:12:06 UT
Lecce, Italy

Venus Transit - Near Third Contact

Venus Transit - Near Third Contact

[1424 x 493 pix - 117k]

Jamie Cooper
June 8, 2004
Northampton, UK

Venus Transit (Egress)

Venus Transit (Egress)

[320 x 240 pix Animated GIF - 383k]

David Brown
LX200 Meade telescope f/6.3
TuoCam
June 8, 2004
Worth Matravers, England, UK
More images at this site

Venus Transit Black Drop Phenomenon

Venus Transit - Black Drop Phenomenon

[350 x 237 - 22k]

Astronomical Observatory Sliven
100/1000mm Cassegrain telescope
SFO80 filter
Praktika camera
June 8, 2004, 11:03:03 - 11:04:20 UT
Sliven, Bulgaria
[See images of the event here.]

Venus Transit - Egress

Venus Transit - Egress

[1280 x 1200 pix - 175k]

Enrico Mariani
Meade ETX90EC f/13.8
Webcam Vesta
June 8, 2004
Tradata (VA), Italy

 

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last modified: 2004/12/29
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