The two satellites graze each other at a speed of 52,800km per hour

IRAS and GGSE-4 satellites are likely to escape the risk of collision above Pittsburgh, Pennsylvania, USA, at 6:39 am on January 30 (Hanoi time).

IRAS satellite in Earth orbit.(Photo: NASA).

Earlier, the ground radar system of LeoLabs, a company that monitors objects operating in low Earth orbit (LEO), tracks the flight path of the IRAS and GGSE-4 satellites. The company warned that they can fly over only 15-30 m apart with a collision rate of about 1/100, very high compared to the standard in the universe.

IRAS launched in 1983 and GGSE-4 launched in 1967. Both satellites have stopped working. Compared to other cosmic debris, they are quite large in size.

Professional and amateur astronomers tracking the two bright 30/1 satellites detected no sign of collision. Jan Kansky, an engineer at the Harvard-Smithsonian Center for Astrophysics, records IRAS videos flying out of danger.

If a collision occurs, the two satellites will shatter and create more space junk. However, LeoLabs also confirmed that his radar system did not detect any new debris.

IRAS and GGSE-4 will continue to float in orbit for a while longer. With SpaceX's Starlink satellite series and many other satellites coming into space, the risk of collisions is likely to increase.

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