Because when I was young, living in an outer suburb of a city I used to drag a couch out into the garden from the back porch at night and lie on my back on it looking at the stars through a pair of 8x40 binoculars.
One summers evening whilst checking out the nebula in orions sword and the stars in the belt a giant asteroid slowly drifted across my field of view.
Must have been big and close to be visible with binocs and well beyond earth's gavity and yet well within the orbit of the moon. I felt like I could reach out and touch it. It was clearly a rock and almost the colour of sandstone although you obviously don't get sedimentary rocks in space!.
I gave the binocs to my sister quickly and told here where to look, but being older she hogged them and didn't give them back quickly. When she did after much begging she didn't give me a reference point, so I never saw it again.
Rest assured it is still out there along with many others in potentially disastrous near earth orbits that have not yet been plotted.
Recently many luminous objects have been mapped due to reflectivity of the suns light. Also a new project has just gone in mapping dark object thats absorb light via thermal imaging.
But we are blind to pretty much anything that comes from the sun side. And as any fighter or space ship pilot should know, the enemy is always hiding in the sun!
One days Earth....Wham. Bam. Straight to the moon!
