The International Space Station was visible to Southeast Texans at 8:45 p.m. Monday night, Aug 5. The $150 billion habitable artificial satellite was visible for only six minutes, appearing from the southwest and disappearing in the northeast.
"Sightings of a wide variety of satellites are fairly common. Usually, however, sightings of the Station are limited to some parts of the country on some days, and other parts of the country on other days," said Bill Tracy, a flight dynamics officer in the Mission Control Center in Houston said in a NASA press release.
Because of the Station's orbit and the rotation of the Earth, the number of sighting opportunities and times will vary from location to location, the website states.
"First, obviously, the satellite must be above the horizon at the observer's location. That's easy enough," Tracy said. "The second requirement is that the observer must be in darkness, when the sun is more than 6 degrees below the horizon. It may not be totally dark, but past experience shows that 6 degrees is about right.
"Third, the satellite itself must be lit by the sun. This means that the sun must be above the satellite's horizon. With the observer in darkness, sightings generally occur near sunrise and/or sunset at the observer's location. Finally, the lit side of the satellite must be facing roughly in the direction of the observer. Even if all other conditions are met, if the lit side of the spacecraft is facing away from the observer, then a sighting cannot take place."
According to NASA's website, there are currently six astronauts aboard the Station, Expedition 36 Commander Pavel Vinogradov, Flight Engineers Fyodor Yurchikhin, and Alexander Misurkin, Chris Cassidy, Luca Parmitano and Karen Nyberg.
The International Space Station orbits the Earth once every 90 minutes, Honolulu's Bernice Pauahi Bishop Museum website states.
"Sometimes it passes overhead in the daytime, when you can't see the station anymore than you can see any bright star. Sometimes the station passes over in the dead of night, when it is cloaked in darkness.
"To see the station, we on Earth need to be in darkness, while the station (220 miles above us) catches the light of the Sun. So good viewing times are either around dusk or around dawn.
"The station will appear much as any satellite, a bright point of light moving steadily across the sky, visible for up to six minutes."