That bright moving star on sky is NASA's International Space Station: Everything you should know

The skygazers in Mumbai witnessed the NASA’s $150 billion International Space Station (ISS) with naked eyes in the evenings on Wednesday. The Mumbaikers will be able to watch it on Thursday, Dec 22 and Friday, Dec 23 as well.

The second day, that is Thursday, will offer the most extraordinary sight when the habitable artificial satellite in low orbit of the Earth will pass between Venus and Mars.

The most extraordinary sight will play out on the second day when the $150 billion satellite passes between Venus and Mars.

People witnessed the first sighting at 6:54 pm on Wednesday. “At that time, the ISS will be visible on Mumbai’s horizon,” said Arvind Paranjpye, director of Nehru Planetarium. 

“It will be in the line of sight of Mumbaikars, and slightly west of true north. At 6.51 pm and 16 seconds, it will climb up to 10° above the horizon. At this point, the satellite will head due north. At 6.54 pm and 2 seconds, it will move in the northeast direction; one should be able to see it passing at a 25° angle above the horizon. The ISS will become clearer as it climbs higher.”

On the first day, the ISS appeared for seven minutes. On the second day, the ISS will be visible for 9 minutes and will occur at 7:35 pm.

“If Mumbaikars face west during this time, they will see a very bright object in the sky. This’ll be Venus. Slightly above it will be a reddish-coloured astral body. That’ll be Mars. Since it will be really dark, both bodies will be easily identifiable. During those 9 minutes, the ISS will pass between both planets.”

The right time to capture the pictures is between 7.36 pm and 7.41 pm.

“One will be able to capture the trails of Venus and Mars, as well as the ISS passing between the two,” said Paranjpye.

The ISS will appear clearer and brighter on Friday and will be visible for 10 minutes on this day. “It will pass right overhead,” said Paranjpye. 

“It will start moving in the northwest direction at 6.41 pm and rapidly climb above the horizon at 6.43 pm. At 6.46 pm, it will be in an almost overhead position. Anyone in Mumbai should be able to spot it at this time.”

About ISS

The first component of ISS, which is now the largest artificial body in orbit, was launched into orbit in 1998.

The ISS can often be seen with the naked eye from Earth. The ISS consists of pressurised modules, external trusses, solar arrays, and other components. Russian Proton and Soyuz rockets, and American Space Shuttles have launched the components of ISS.

The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology, and other fields

The station is suited for the testing of spacecraft systems and equipment required for missions to the Moon and Mars.
Five space agencies - NASA, Roscosmos, JAXA, ESA, and CSA – are involved in the ISS programme.

The station is divided into two sections, the Russian Orbital Segment (ROS) and the United States Orbital Segment (USOS), which is shared by many nations.