International Space Station Viewing

The International Space Station (ISS) will be visible from the USVI many times in the next week. The ISS is very large due to its solar panels and other equipment, making it the most visible man-made satellite, and it appears about as bright as Venus. It can be seen even in twilight when no stars are yet visible, and it can be seen even in areas with light pollution. The ISS, and low earth orbit satellites in general, can be seen just after sunset and just before sunrise, when the sky is dark and the satellite is lit by sunlight.

Here are the ISS viewing times, compass directions, and altitudes. The data is updated continuously, so you can view it any time for the next 10 days.
For STX: http://www.heavens-above.com/PassSummary.aspx?satid=25544&lat=17.72776&lng=-64.7644&loc=St.+Croix&alt=0&tz=UCT4
For STT/STJ (at Red Hook): http://www.heavens-above.com/PassSummary.aspx?satid=25544&lat=18.32584&lng=-64.8519&loc=St.+Thomas+Red+Hook&alt=0&tz=UCT4
Please re-check the pages as you get nearer to each date, because sometimes the data changes.

The given “altitude” is the number of degrees above the horizon. Horizon = 0 degrees, and directly overhead = 90 degrees. Most passes start and end at 10 degrees, because below that the atmosphere gets in the way. If a pass starts or ends at a number higher than 10, it’s because the ISS is in the earth’s shadow before or after that. The higher the altitude, the brighter and longer it will appear, and the easier it will be to see. For example, a pass with a max altitude of 12 degrees is very hard to see, and a pass of 80 degrees is very easy to see (assuming it’s not cloudy).

The given times are in 24-hour format. 19:30 means 7:30pm. 05:15 means 5:15am.

To synchronize your watch: http://www.heavens-above.com/whattime.aspx?lat=17.72776&lng=-64.7644&loc=St.+Croix&alt=0&tz=UCT4

For other parts of the world, you can start at http://www.heavens-above.com/ and find your location.

You can recognize a satellite from an airplane because a satellite doesn’t blink, and doesn’t make any noise. Sometimes a satellite will flare, which means it briefly reflects sunlight directly to earth via a flat reflective surface such as a solar panel.

The ISS orbits at an average of about 211 miles above sea level, and each orbit takes about 91 minutes.