The James Webb and Hubble telescopes on Thursday revealed their first images of a spacecraft deliberately smashing into an asteroid, as astronomers indicated that the impact looks to have been much greater than expected.

While those images showed matter spraying out over thousands of kilometers, the James Webb and Hubble images "zoom in much closer", said Alan Fitzsimmons, an astronomer at Queen's University Belfast involved in observations with the ATLAS project.

James Webb and Hubble can offer a view "within just a few kilometers of the asteroids and you can really clearly see how the material is flying out from that explosive impact by DART", Fitzsimmons told AFP.

An image taken by James Webb's Near-Infrared Camera (NIRCam) four hours after impact shows "plumes of material appearing as wisps streaming away from the center of where the impact took place", according to a joint statement from the European Space Agency, James Webb and Hubble.

Ian Carnelli of the European Space Agency said that the "really impressive" Webb and Hubble images were remarkably similar to those taken by the toaster-sized satellite LICIACube, which was just 50 kilometers from the asteroid after separating from the DART spacecraft a few weeks ago.