Hundreds of asteroids approach Earth every year and while some of them enter the atmosphere, most of them either pass by the planet or get trapped by its gravity. NASA experts have detected one such incoming asteroid that will be trapped by Earth's gravity and will become a "mini Moon" for some time. However, what appeared to be an asteroid, turned out to be an old rocket that was sent to the Moon in the 1960s.
Dubbed as 2020 SO, the new Moon would circle around Earth from October 2020 to around May 2021. However, unlike an asteroid, the object is approaching Earth at 1,880 miles per hour or 3,025 kmph. That is considered slow for an asteroid and that's the reason, experts argued that it could be man-made space junk. Based on its brightness, experts believe that the object has a diameter of around eight meters.
The low velocity first caught the attention of the experts. While Moon rocks also have lower velocity when they approach Earth, 2020 SO is even slower. "The velocity seems to be a big one. What I'm seeing is that it's just moving too slowly, which reflects its initial velocity. That's essentially a big giveaway," Alice Gorman, a space archaeologist at Flinders University told ScienceAlert.
Paul Chodas, manager of the NASA NEO Program Office at Jet Propulsion Lab (JPL), suggested that the object could be a Surveyor 2 upper rocket stage that was launched on September 20, 1966, atop an Atlas LV-3C Centaur-D rocket. But failure in mid-course correction led to NASA losing contact with the ground.
In this case, the multi-stage rocket's boosters fell back on Earth while the other half of the rocket transported the payload to Moon. However, the lander crashed on Moon but the upper stage rocket traveled past the satellite and became a space junk. But it appears that the junk has come back to its origin.
The other aspect that attracted Chodas' attention was the object's near-circular orbit around the Sun. He believes that is unusual for an asteroid. In addition, unlike asteroids that fly by Earth at odd angles, 2020 SO's flight path isn't tilted. All those factors led him to believe that it could be a man-made object rather than an asteroid. As the object approaches Earth, experts including Chodas will be able to take a closer look and use spectroscopic observations to better understand what the object is.
It's, however, not the first time that a man-made object has come back to Earth. In 2002, Chodas and his team detected an object that appeared to be a man-made object. After a year of orbit, the object drifted off into deep space. He believed that the object was the Saturn V rocket's third-stage from 1969 that was used for the Apollo 12 mission. It was the second time that astronauts landed on Moon.
Another object As WT1190F approached Earth and entered its atmosphere in 2015 appeared to be an asteroid but spectroscopic analysis suggested that it was man-made space junk. It disintegrated upon entering the atmosphere on November 13, 2015.
"I could be wrong about this. I don't want to appear overly confident. But it's the first time, in my view, that all the pieces fit together with an actual known launch," Chodas told the Associated Press.