Asteroid 163899, also known as 2003 SD220, is a potentially hazardous asteroid about 1.5 miles across and it is expected to pass perilously close to Earth on December 24, Christmas Eve, according to NASA astronomers.
Asteroid 2003 SD220 is one of the biggest, near Earth asteroids (NEAs) to make such a close approach to Earth in recent years. The asteroid is so big that it could cause continent-wide catastrophe if it hits Earth. An impact by an asteroid in the 1.5-mile-range could trigger earthquakes and tsunamis that could engulf an entire continent.
Astronomers are concerned about 2003 SD220 because it is one of the largest NEAs to make a close approach to Earth in recent years. At an estimated distance of 6.7 million miles — a hair’s breadth on the cosmic scale of distances – it could come on a collision course with Earth in the future due to physical effects, such as the Yarkovksy effect which induces subtle changes in the orbits of NEAs.
Astronomers have detected two cases of Yarkovsky effect using radar observation methods. The effect was first detected in the asteroid 6489 Golevka using the Arecibo radio telescope. The asteroid was observed to drift 15 km from its original course over a twelve-year period from 1991 to 2003.
According to NASA, asteroid 163899 (2003 SD220) was detected by the NEOWISE spacecraft on November 16. The asteroid is high on the list of 17 “top-priority” near-Earth asteroids for close radar observation by astronomers due to the potential threat they pose to Earth.
Astronomers fear that ten of a group of asteroids — including 2003 SD220 — could be much larger than suspected. Six of the group — including 2003 SD220 — are classified as potentially hazardous asteroids (PHAs).
The six are considered potentially hazardous asteroids because scientists know too little about their trajectories despite the fact that their orbital trajectories bring them very close to Earth.
Space rocks falling into the PHA category are generally larger than 100 meters and approach Earth closer than 0.05 AU (approx 7.5 million kilometers or 4.65 million miles).
Currently, NASA does not know of any PHA on a collision course with Earth but astronomers are searching actively. There is a risk that the trajectory of any of the known objects could undergo subtle changes due, for instance, to the gravitational fields through which their orbital paths pass that could bring them on collision course with Earth.
Reports of the close approach of asteroid 2003 SD220 on December 24 have sparked speculations online among Planet X or Nibiru cataclysm believers. Conspiracy theorists are spooked by the timing of the approach of 2003 SD220, following the close approach of asteroid 2015 TB145 last Halloween. Some conspiracy theorists are speculating that some invisible hand could be “pushing them (large asteroids) towards Earth,” while others are speculating that the gravitational pull of 2003 SD220 could trigger earthquakes and disrupt continents.
The force of its gravitational pull as it passes close to Earth will rip up the continents and cause a massive shower of comets that wipes out life from Earth, according to conspiracy theorists.
But, of course, conspiracy theorists have predicted Planet X or Nibiru cataclysm for decades and so far their predictions of doom have failed.
NASA astronomers with the Near-Earth Objects Observation program and astronomers at the Arecibo observatory in Puerto Rico will conduct radar observations of 2003 SD220 as it approaches Earth. Radar observation is considered one of the most effective techniques for determining the physical and orbital properties of NEAs and PHAs.
According to a report by a team of experts working with NASA, “Radar is particularly effective at detecting satellites around near earth asteroids having discovered two-thirds of all known binaries and all the known or suspected triple systems.”
[Image via NASA/Wikimedia]