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Well my arrows are made of Desire, 
from far away as Jupiter's sulphur mines!

Say my arrows are made of Desire, Desire...
from far away as Jupiter's sulphur mines-
way down by the Methane Sea, ha! ha!

- Jimi Hendrix

Simultaneous transit of the ISS and Venus - Tomas Maruska

Updated 5:00 UTC, June 8

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More on Tomas Maruska's unique photo / video of the International Space Station transiting Venus transiting the Sun!

If you have previously viewed this webpage, it may be necessary to click on your browser's Refresh button (or press F5, in Microsoft Internet Explorer), to see updates.

Below are text files specifying ISS / Venus transit-track latitudes, longitudes and times (all times are Universal Coordinated Time / UTC), based up Mission Control Center tracking data^, June 7.  It's recommended that, to observe a transit of Venus by the ISS, you locate as near the transit path as possible (e.g., 10 to 100 meters).

ISS / Venus transit track - June 7 final predictions Orbit-1  Orbit-2  Orbit-3  Orbit-4  Orbit-5

Local Maps
Orbit-1  Orbit-2  Orbit-3  Orbit-4  Orbit-4_Cape_Verde  Orbit-4_Brazil  Orbit-5

The maps are simple graphic files in the .gif format, and are in chronological order.  Just click on them, and they'll be displayed in your browser (go ahead and try the Cape Verde one, since there is only one; use your browser's back-arrow to return here).

For the purpose of comparison, here are the predictions from June 4:

ISS / Venus transit track - June 4 predictions 1  2  3  4  5

Shown below is a worldwide map of the ISS / Venus transit track, based upon a prediction made on June 3 (on the scale of this map, the actual track will not differ from what is shown here).

Worldwide map of ISS/Venus transit track

Archived discussion
ISS Transit main page
Shameless self-promotion

Looking directly at the sun, with your eyes or with binoculars or a telescope (unless it's fitted with a solar filter, that blocks 99.99% of the light), can permanently damage your eyes.  However, it's possible to use binoculars indirectly to view, and even photograph the Sun: binocularCamera.html^

A simple way to use binoculars to safely view the Sun

Below, I've plotted the June 4 prediction with the June 7 prediction, in the area of Lodi, Italy.  Unfortunately, Microsoft Streets & Trips has limited resolution outside of the U.S. and Canada.

So, to create a clearer comparison, I shifted everything 100░ west, to put it inside the U.S.  That plot, which follows the Lodi plot, shows that the June 7 prediction (in the area of Italy), moved about 222 meters northwest, and was delayed by about 1 second, compared with the June 4 prediction.

If the error from June 7 to June 8 is proportional, then it will amount to only about the size of the ISS itself.

June 4 transit path prediction vs. June 7 prediction

A clearer (but fakey) comparison

Using the "transit paths" I've posted, it will be possible for observers along the path to see the silhouette of the ISS pass briefly across the face of the Sun, and Venus itself, while Venus is passing in front of the Sun (the dark circle is Venus, and the gray circles are the ISS, at split-second intervals along the path taking it across the disk of the Sun & Venus):

Image credit: Arnold Barmettler & CalSKY

With the help of John Locker^, Arnold Barmettler has put together an informative web page, with links to other information, here:^

For my predictions, I used information from NASA's Mission Control Center, in Houston, Texas.  CalSKY uses that same information to make predictions that are more than a day or two into the future, but uses information from NASA's Orbital Information Group for near-term predictions.

At about 2:30 UTC (i.e., 3 hours before the event) I entered my prediction for "Contact 2"- when Venus is first entirely within the disk of the Sun, at 5:32:55 UTC- into CalSKY, which indicated that from that spot, the ISS would miss Venus by a significant amount.  The 2-line element^ orbital data being used by CalSKY at that time was the following:

1 25544U 98067A   04159.93711806  .00014804  00000-0  13139-3 0  9452
2 25544  51.6330  12.8933 0005507 205.7066 355.6711 15.68799899316862

The orbital data I used was this:

1 25544U 98067A   04159.51929753  .00020000  00000-0  20000-3 0  9009
2 25544  51.6330  15.0298 0005537 207.1571 152.9300 15.68796178 36803

Entering both TLEs into Rob Matson's SkyMap 6.6^ program, and using the transit position I predicted for 5:32:55 UTC (45.9176░N, 80.9990░E; using the MCC TLE), gave the following result:

MCC vs. OIG TLE comparison

SkyMap confirms a "dead hit" if the MCC TLE proves to be accurate, and also confirms a significant miss of Venus if the OIG TLE proves better.  (It's now almost 5:00 UTC, or about 35 minutes prior to the event, and CalSKY is still using the OIG TLE above).

Transiters, choose your weapon!

The likely 3D orientation of the ISS, as it passes in front of the Sun in the area of Milan, Italy, is depicted below by the ISS VRML simulator^, developed by Mike Tyrrell^ and Phil Masding^; it will be traveling in the direction of the green line.  Based upon^ "NASA Space Station On-Orbit Status 4 Jun 2004^," I assume it to be in the XPOP^ orientation.

Though obscured by the glare of the Sun, the Pleiades star formation (near the tip of a solar panel) will be to the right, and above the Sun:

Likely 3D orientation of the ISS passing over Milan, Italy, June 8, 2004

Shown below is a composite photograph, made by Roland Stalder in Luzerne, Switzerland, of the ISS transiting the Sun on August 16,  2003, to which I've added a fake Venus.  

For size comparisons, the Sun has an angular diameter of about 30 minutes of arc ( 30' ), or half a degree ( 30 / 60 ).  Venus currently has an angular size of about 1', or 58 seconds of arc ( 58" ) to be more precise ( 58 / 3600 of a degree ).  For a high-elevation pass, the ISS will be about 410 km / 255 mi distant, and the 73 meter / 240 foot width of its main solar panels will have an angular size of about 37" of arc (if oriented perpendicular to the line of sight).  Bottom line:

the ISS will be appear to be about 2/3 the size of Venus, for a good pass.

Roland's 1000 frame-per-second !!! video of this solar transit may be viewed here.

- 5 June 2004 -

June 8, 5:00 UTC, clear skies, good luck, and...