1998 QE2 zipped past Earth in the afternoon. Just before 2 p.m., it was at its closest point, some 15 times the distance from us to the moon, or 3.6 million miles away.
The asteroid is believed to be about 1.7 miles in diameter, or about nine Queen Elizabeth 2 cruise ships, which the asteroid is not named after. 1998 QE2 is just a scientific tag for the huge space rock, which NASA scientists say rotates every 5.3 hours.
If 1998 QE2 decided to visit us, astronomers say it would not be fun to experience.
"If an object that large were to crash into earth, it would be devastating. It would be extinction-causing," said Laura Danly, Griffith Observatory curator.
But still, NASA experts will tell you visits like these should be considered a shot across the bow, and a good example of why Congress needs to fund programs to protect against killer space rocks.
Fortunately, the space agency isn't predicting any catastrophic asteroid-earth collisions in the next 100 years. NASA discussed plans Thursday to study a way to move future asteroids that could pose a threat.
"The question that we always get is, 'can we protect the planet?' The answer to that is no, right now," said NASA Administrator Charles Bolden. "But if we're able to demonstrate that humans are able to redirect an asteroid or deflect it in some slight way, we may be getting close to the day that we say, yes, we can protect the planet."
1998 QE2 was first discovered back in 1998, but some latest images show a small white object which scientists believe is the satellite or moon orbiting the asteroid.
"It's definitely possible to see with a small amateur telescope, even from near JPL here where there's a lot of light pollution," said Steve Wissler, a Jet Propulsion Laboratory astronomer.
It's so far away that even at its closest point, telescopes are only be able to see it as a small point of light.
"We don't know of any asteroids that have a significant chance of hitting the Earth right now," said Chodas.
The experts are quick to point out that there are no guarantees, which doesn't sit well with some folks.
"I guess all we can do is hope and pray," said Griffith Observatory visitor Allan Gumapus.