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Earlier quoted context omitted.
It's not impossible. How closely were we tracking 3 km objects in 1983?
The US and USSR were looking very closely for much smaller objects leaving and entering the atmosphere.
Notice that this was spotted by an amateur only 2 weeks before closest approach. Why was it not found by the larger installations? One problem I like to repeat at times like this, is that these hunts for near earth asteroids look for bright spots that move against the background stars. That's a nice way to find things nearby. But any object on a collision course with earth will not be moving against the background in…
Congress mandated that NASA construct a surveillance capability for relatively-large NEOs (larger than the ones in OP), so the detection problem has been well-studied. A little googling will turn them up, but here's what I remember: - Detection in optical by ground-based telescopes is a good technique. You need several exposures and good spot-tracking. Because of the relatively short time-base, you also need good fol…
Earlier quoted context omitted.
But with computers and sky tracking charts shouldn't it be trivial to find new spots in the sky without using parallax? Anything new should be pretty note worthy.
Not all asteroids are “bright” enough to be imaged from earth, the problem is the low albedo asteroids you cant see, thats why we need this: https://solarsystem.nasa.gov/missions/neo-surveyor/in-depth/
Earlier quoted context omitted.
Congress mandated that NASA construct a surveillance capability for relatively-large NEOs (larger than the ones in OP), so the detection problem has been well-studied. A little googling will turn them up, but here's what I remember: - Detection in optical by ground-based telescopes is a good technique. You need several exposures and good spot-tracking. Because of the relatively short time-base, you also need good fol…
None of those links addresses the problem. Finding NEOs is important because they pass by repeatedly and can be tracked. My point is that one on a collision course is not detectable with that method of looking for motion against the background.
My understanding is that the robotic scanning telescopes can detect these objects, but that unless they get a high-quality track, the telescope has already moved on with its scan and the NEO will be lost. That is, detection is hard, but tracking is harder, and you need tracking.
And I guess my comments are also directed at the "systems" aspect of the NEO protection problem - detection, tracking, followup.