Astronomers tracking asteroid 2014 J025 need not look far to examine the rock. The space object comfortably brushed by Earth on April 19. Scientists have been tracking the asteroid since 2014, and NASA has recently warned the public about the passing of the mile-wide asteroid.

"Although there is no possibility for the asteroid to collide with our planet, this will be a very close approach for an asteroid this size," a NASA official from the Jet Propulsion Laboratory said in a statement.

The mile-wide mega asteroid, also known as "the rock," passed by the planet on April 19, and came close at over one million miles (1.8 million kilometers). Scientists call it the "comfortable" phase since it is very unlikely to collide during transit.

Although not fatal, some experts say that smaller and less risky asteroids do pass the Earth at even nearer distances than "the rock." Asteroid 2014 JO25 is not unlike frequent, smaller asteroid -- it's gigantic with a reflective surface such as the moon. It's about 2,000 feet, making it the largest asteroid to approach Earth within this proximity since 2004. 

"We know the time that the object is going to be closest within seconds, and the distance is known within hundreds of kilometers (miles)," Davide Farnocchia mathematician at Nasa's Near-Earth Object program, said in an interview.

Since astronomers have been looking at this particular asteroid since early 2000, they were able to predict its path. With its proximity, it can be seen in the sky using a telescope. The naked eye has difficulties identifying the asteroid in a sea of stars. The space rock is expected to be visible for a couple of days starting April 19.

"The rock" despite its ferocious name is harmless to Earth. However, by itself, its energy is equivalent to 1,000 atom bombs. Despite not being an asteroid with "extinction level" credibility, experts warn that an impact from an asteroid this size would yield a calamity or global significance.