The International Space Station, a habitable satellite, is the largest artificial satellite in space that orbits our planet Earth. Because of its massive size, we human beings can see it through our naked eyes from Earth.
If you go out for a stroll and spot a bright thing in the sky, it could be the ISS. The ISS orbits the Earth at a speed of 8 km/second and at a distance of 400 kilometers, which is why people manage to take a glimpse of it very often. In a day, it revolves around the Earth 15 times.
The ISS is basically a microgravity and space environment research laboratory which helps scientists carry out experiments in biology, human biology, physics, astronomy, meteorology, and other fields.
Also, the testing of spacecraft systems and equipment for missions to the Moon and Mars are conducted in the ISS.
The ISS sighting website
You can logon to the ISS sighting website and search your locations there. It will show you the date and time to view the ISS. If you fail to find out positive search results for your location, then it will find you near by places from where you can spot ISS.
How to spot the ISS
Within a few hours before or after sunrise is the best time for ISS sighting. During this period the sun reflects off the ISS and its contrasts against the darker sky.
The Max Height, which represents the height of the International Space Station, is measured in degrees, known as elevation. The horizon is at zero degrees while directly overhead is 90 degrees. Hold your fist at arm's length and place it resting on the horizon, then the top should be about 10 degrees.
Appears represents the location where the ISS would be first visible. This value is also measured in degrees from the horizon. The letters represent compass directions — N for north, WNW for west by northwest, and so on.
Disappears is where the ISS will leave your field of view.
The ISS appears as an airplane or a bright star moving in the sky, however, it doesn't have a flashing light. Also, compared to an airplane, it moves considerably faster.
Airplanes generally fly at about 600 miles (965 km) per hour, while the ISS flies at 17,500 miles (28,000 km) per hour).
Some facts about the ISS
#The International Space Station is not bright enough to be viewed during the day. So, the right time to see it is dawn or dusk at your location.
#Sighting opportunity ranges from one a month to several a week as it has to be dark and ISS has to be moving overhead.
#The International Space Station is the third brightest object in the night sky.
#Till date, 226 persons from 18 countries have visited the International Space Station.