Just over a week after a meteor exploded across the sky above the Chelyabinsk region of Russia, a group of astronomers published a paper that reconstructs where the rock came from. The men in question were Jorge Zuluaga and Ignacio Ferrin at the University of Antioquia in Medellin, Colombia. And the method they used was quite unconventional, and is perhaps a testament to the age we live in.
Basically, Zuluaga and Ferrin used the many sources of dashboard and security cameras that captured the event on film. Using the trajectories shown in the videos posted on YouTube, the researchers were able to calculate the trajectory of the meteorite as it fell to Earth and use it to reconstruct the orbit of the meteoroid before its fell to Earth and cause the shockwave that damaged buildings and shattered windows.
From their calculations, they were able to determine the height, speed and position of the meteorite as it fell to Earth. According to the team’s paper:
“…the Chelyabinski meteor started to brighten up when it was between 32 and 47 km up in the atmosphere. The velocity of the body predicted by our analysis was between 13 and 19 km/s (relative to the Earth) which encloses the preferred figure of 18 km/s assumed by other researchers.”
They then used software developed by the US Naval Observatory (called NOVAS) and the Naval Observatory Vector Astrometry to calculate the likely orbit. From all this, they came to the preliminary conclusion that the meteorite came from the Apollo class of asteroids, a well-known class of rocks that cross Earth’s orbit.
This conclusion has some worried, since the Apollo group, which orbits the Sun in the vicinity of Venus and Earth, contains over 2000 asteroids that are larger than 1 km in diameter. And considering that this one meteor, which measured between 17 and 20 meters, caused 1491 injuries and damage to over 4000 buildings in the area.
Lucky for us, NASA and every other space agency on the planet has some defensive strategies in mind. And of course, early warning is always the most important aspect of disaster preparedness. In the near future, we can expect some of the proposed observation satellites that will be going up to ensure there will be a better degree of early warning.