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Two days after DART’s impact of Dimorphus, ejected dust extends like a comet tail out more than 6,000 miles

Dust tail from Dimorphus two days after DART impact
Click for full image.

Using a telescope in Chile, astronomers photographed the ejecta two days after the impact of DART into the 525-foot-wide asteroid Dimorphus, and detected a tail of dust extending out more than 6,000 miles.

The picture to the right, cropped and reduced to post here, shows that tail.

In this new image, the dust trail — the ejecta that has been pushed away by the Sun’s radiation pressure, not unlike the tail of a comet — can be seen stretching from the center to the right-hand edge of the field of view. … At Didymos’s distance from Earth at the time of the observation, that would equate to at least 10,000 kilometers (6000 miles) from the point of impact.

Didymos is the larger parent asteroid that Dimorphus orbits.

It is still too soon to get the numbers on how Dimorphus’s path in space was changed by that impact. In fact, we still really don’t have a clear idea what is left of Dimophus itself. The ejecta cloud needs to clear somewhat to see what’s hidden inside it.

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  • Jerry Greenwood

    It will be interesting to see the numbers when they come out and how closely they equate to the expected results. If the estimate (guess?) of the mass of the parent and it’s satellite are accurate, and knowing the velocity and mass of Dart, the numbers should be very close. The only variable would be how close to the center of Dimorphus’ CG the Dart struck.

    Keep us in the loop.

  • Jerry Greenwood: There are other variables that could not be measured in advance. For example, the structure of Dimorphus could be strong, or weak. If a rubble pile, for example, it would be very weak. In that case predicting the outcome is more difficult. It could break up into a cloud of debris that will slowly coalesce back together, or be flung apart. It would also be hard to predict how much breakage there would be.

    The images and subsequent large cloud (larger than expected) suggest a rubble pile.

  • sippin_bourbon

    Wondering if that trail means that it is more of a dust pile, rather than a rubble pile.

  • Max

    The early pictures suggest a rubble pile. It appears the rocket had an effect like a bullet hitting a watermelon.

  • Ray Van Dune

    sippin_bourbon: “Wondering if that trail means that it is more of a dust pile, rather than a rubble pile.”

    Perhaps it means a hunk of it was shattered / shocked into a dust pile?

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