Small Asteroid Discovered Orbiting Earth (cnn.com)

Frosty Piss writes from a report via CNN: A small asteroid has been found circling Earth. Scientists say it looks like the asteroid, named 2016 HO3, has been out there for about 50 years. Calculations indicate 2016 HO3 has been a stable quasi-satellite of Earth for almost a century, and it will continue to follow this pattern as Earth's companion for centuries to come. Scientists think the asteroid is between 120 and 300 feet (37 to 91 meters) in diameter, and NASA says it never gets closer than 9 million miles (14 million kilometers) from Earth. It was found on April 27, 2016 by the Pan-STARRS 1 asteroid survey telescope in Haleakala, Hawaii. So how do we miss a 300 foot object that has been orbiting the Earth for around 50 years? Probably the same way we've missed all the flying saucers!

Comments

Re:To put it into perspective

[Kokuyo]

Jeez, what a surefire way to be wrong you've chosen. Others already commented on the infinite time frame you've chosen but I'd like to add that "cost effective" is pretty relative.

There just needs to be a shortage of material found on an asteroid that is either life threatening or lowers our quality of life enough for people to decide they're going to try it.

And why should this never be cost effective? Robotic mining equipment needs to be deployed once. And without much gravity to speak off, all you need to do is launch the mined material in the direction of a desert every few days.

Can't be that hard to accomplish.

3e-09 radians, 5e-19 stradians. in just 50 years??

[140Mandak262Jamuna]

Quick mental calculation shows that object is subtending 3e-09 radians at Earth. Need back of the envelop for solid angle. About 5e-19 stradians if it its a ball 300 feet across. Give or take a few orders of magnitude.

Now the question is not "how come we missed it for 50 years?". The question is "how come we found it in just 50 years! OMG our astronomers are awesome!".