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Wow, that's the first step!

However, the most efficient method would be actually land (I know - maybe even impossible?) on it, and use propellers to change its trajectory. We don't have too much throwaway high-tech to crash it on asteroids...

Interesting. I'd not considered the loss of mass as a means of propulsion.

Obviously there was the kinetic energy transfer but the impact ejacted some of the asteroids mass opposite to it's trajectory further increasing it's trajectory change.

Cool demonstration, hopefully not needed one day.

When the impact happened the news articles seemed to imply some surprise about that as well which seemed strange to me. I just wrote it off to the journalist just not being up to speed on the subject matter. The size of the debris field trailing also seemed to be a surprising result.
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> ...I wonder how much kinetic energy it had...

Since kinetic energy is proportional to v squared, that highly depends on how you measure v...

Well done, DART, which country did you aim it to?
I'm annoyed at these nothing-burger titles...

Instead of pointing out that exact measurements finally came in (of long term movement change), journalist instead focused on the obvious outcome that everyone expects and knows

Wild that we went from "can we even deflect an asteroid" to measurably changing a solar orbit. 150 milliseconds sounds tiny until you realize compounding over decades makes that a meaningful trajectory shift. The engineering confidence this gives for actual planetary defense is massive.
I find it mesmerizing how predictable orbital mechanics are. We can tell where celestial body will be years ahead with meter accuracy.
Well, the article says that the effect of the impact was much larger than the scientists expected. That doesn't really give a lot of confidence in how good we are at predicting these things.
Makes you wonder how many other objects were sent on new trajectories by even smaller influences
> The engineering confidence this gives for actual planetary defense is massive.

Is it? Isn’t it the case that we can’t even detect the vast majority of objects on a potentially problematic intersection path with earth? I feel like the most likely scenario is that by the time we realize we’re about to get slammed by an asteroid, it’s way too late.

Is debris a problem? I think the ideal would be to embed or clamp a rocket on the target.
Some have suggested attaching a solar shield to objects to add drag to alter the course. However, that would require a much more precise landing and some sort of drilling/anchoring effort. A kinetic impact like this is always going to be more efficient.
> slowed the orbit of a pair of asteroids around the sun by more than 10 micrometers per second

Or in other words, 1 meter per day

Why not say that?

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What is the feasibility of changing asteroid orbits to impact a specific location on earth? What is the circular error probable with current technology?