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Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

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Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#4
"Maybe the big take-home point on this one is it's a pretty big object and it was only found 10 or 12 days before closest approach,"

I've said this before. The way they find these things is looking for movement against the distant background / starfield. That works pretty well for finding things, but there is one problem. Any object on a collision course with earth will NOT be moving across the background in the days leading up to the collision. It will appear stationary against the stars, so will not be detected by these systems. To some extent it also doesn't matter that we are orbiting the sun because while near, earth and asteroid will be in the same accelerating reference frame.

Another way to model it is to think of firing a projectile from earth into deep space and see how that tracks against the background. That'd be the reverse scenario and there will be no relative motion until it's far enough to not get the same influence from the sun.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#5
How large? "anywhere from 120 metres to 260 metres in diameter".

Is that bad? According to NASA, "If a rocky meteoroid larger than 25 meters but smaller than one kilometer ( a little more than 1/2 mile) were to hit Earth, it would likely cause local damage to the impact area. We believe anything larger than one to two kilometers (one kilometer is a little more than one-half mile) could have worldwide effects."

So... it would really suck if it hit a populated area, though that's unlikely.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#6
post #4

"Maybe the big take-home point on this one is it's a pretty big object and it was only found 10 or 12 days before closest approach," I've said this before. The way they find these things is looking for movement against the distant background / starfield. That works pretty well for finding things, but there is one problem. Any object on a collision course with earth will NOT be moving across the background in the days…

One more reason for deep space telescopes. A PHA about to impact will not have much movement in relation to the background stars when seen from Earth, but will be moving when seen from a different vantage point.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#7
post #4

"Maybe the big take-home point on this one is it's a pretty big object and it was only found 10 or 12 days before closest approach," I've said this before. The way they find these things is looking for movement against the distant background / starfield. That works pretty well for finding things, but there is one problem. Any object on a collision course with earth will NOT be moving across the background in the days…

Sounds like we need a monitoring station on Mars.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#8
post #2

Was funding for the Asteroid Watch program drastically reduced, or why did the detection come in so late? https://www.jpl.nasa.gov/asteroid-watch

I'm confused about the late warning quote because the data page for MK2024 shows the first observation for the orbit fit was 2024-05-07.

https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2024%...

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#9
post #5

How large? "anywhere from 120 metres to 260 metres in diameter". Is that bad? According to NASA, "If a rocky meteoroid larger than 25 meters but smaller than one kilometer ( a little more than 1/2 mile) were to hit Earth, it would likely cause local damage to the impact area. We believe anything larger than one to two kilometers (one kilometer is a little more than one-half mile) could have worldwide effects." So...…

I'm surprised there's no TNT equivalent comparing it to the biggest weapons humans have created. That always seems like a data point used when showing destructive forces.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#10
post #8
post #2

Was funding for the Asteroid Watch program drastically reduced, or why did the detection come in so late? https://www.jpl.nasa.gov/asteroid-watch

I'm confused about the late warning quote because the data page for MK2024 shows the first observation for the orbit fit was 2024-05-07. https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2024%...

So even if they announced on the day of the first observation, that's not really much notice to do anything about it other than start prepping for accepting of loss of life. I would seriously hope it took some amount of time for other people to verify/validate trajectory than the first person that observes it.

At this point, we're still at the point of needing years if not decades notice for us to even have a chance of actually protecting from an impact in a meaningful way.

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