Mark McCaughrean | But because we have been watching HH211 for many years, we can also watch how the jet is expanding over time. Here's a comparison between the 2002 VLT 2.12 micron image & the 2022 JWST one at the same wavelength. The expansion is clear, even despite the change in spatial resolution. The jet is expanding at about 100km/s overall, but seems to be decelerating towards the top-left (NW) end, perhaps as the jet crashes into denser material in the region.
