ISS Transits the Lunar Surface, Sunday, July 31st, 2011

Good morning and welcome to yet another ISS Transit opportunity...
This time the ISS will transit the Moon!

On Sunday morning, July31st, 2011, at 09h 06m 53.92s EST the ISS will transit the Moon as it is low on the Eastern horizon. At 17 degrees altitude this would be an almost impossible apparition except for the fact that the Lunar disk will be transited at Sherod Park in Vermilion, Ohio overlooking Lake Erie. This will result in an unprecedented, unobstructed Eastern horizon.
As a result of the steep angle between the observer, the ISS and the Moon, the Space Station will take over two whole seconds to complete it's journey across the face of the Lunar Surface. This could place the transit within the reach of still photographers. (Set the camera in burst mode and hold the shutter down!) Guys shooting 30 f/s will capture ~60 images and guys shooting 70 f/s will record a whopping 140 something seperate frames of the transit.
A major detractor of this event is that the Sun will only be 11 degrees away from the Moon at the time of transit, creating some obstacles we will need to prepare for and overcome,including:
First, the Moon will be hard to locate at this distance from the Sun.
Second, there won't be a lot of contrast, and
Third, extreme caution will need to be exercised to prevent accidentally pointing imaging devices and unprotected eyes at the Solar Surface.

 More details to come soon....

Astronomically, Dr. John

ISS/Lunar Transit DataSheet:
ISS crosses the disk of Moon. 
Separation=0.116°  
Position Angle=271.0°, 
Position angle vertex=320.8°.  
Transit duration=2.01s
Angular diameter=25.8"  
size=109.0m x 73.0m x 27.5m
Satellite at Azimuth= 90.6° E    
Altitude= 17.1°  
Distance=1070.0 km  
Magnitude=2.3mag
In a clock-face concept, the satellite will seem to move toward  4:19
Angular Velocity=14.5'/s

Centerline, closest point →Map: Longitude= 82°13'42"W  Latitude=+41°21'59" (WGS84) Distance=3.45 km  
Azimuth=200.3° SSW  
Path direction=110.3° ESE  
ground speed=10.417 km/s  
width=10.8 km  max. duration=2.2 s
Sun elevation=+29°  
Elongation from Sun=11°
Orbit source: NASA predicted orbit