2
$\begingroup$

enter image description here

Source: https://images.indianexpress.com/2023/08/An-ISRO-image-of-the-Chandrayaan-3-landing-site-taken-after-touchdown.-One-of-the-four-legs-of-the-lander-is-visible-on-the-right-1.jpg?w=414

If you see the landing surface of Chandrayaan-3, there is no loose soil left underneath the landed but in Apollo-11, it showed the foot print just below the lander. Let’s say it’s not thin layer of dust but with huge rocket engine it creates immense pressure and will likely to blow away the dust. Newton 3rd law works in vacuum as well. So, how come there is no dust in the landing site of Chandrayaan-3?

Improve this question
$\endgroup$
5
  • 5
    $\begingroup$ I am reasonably sure that it's documented that Apollo missions blew dust away to a noticeable degree as well. $\endgroup$
    – ikrase
    Commented Aug 24, 2023 at 2:51
  • 4
    $\begingroup$ There is substantial evidence that plenty of dust and indeed small rocks were blown away during the Apollo landings. Dust (regoligh) thickness varies by quite a lot on the Moon, and I can imagine that the mission planners chose a landing spot where the lander would not end up knee-deep for science and practical reasons. A lot more is known about the surface of the Moon now than was in 1969. For average thickness variation see How thick does lunar regolith ever get? Has the thickness been measured and mapped by satellite? $\endgroup$
    – uhoh
    Commented Aug 24, 2023 at 3:58
  • $\begingroup$ But I think there is a good question here - I wonder how think the regolith (dust) was before it landed - maybe they targeted a clean outcropping of rock to begin with. Is there any close-up imagery of the site just before landing? $\endgroup$
    – uhoh
    Commented Aug 24, 2023 at 3:59
  • 2
    $\begingroup$ From 13:30 on this video of the Apollo 11 landing dust can be seen to be blown away by the LEM as it is landing. At 13:50 the comment is made by Aldrin, "picking up some dust". $\endgroup$
    – Fred
    Commented Aug 24, 2023 at 7:27
  • 5
    $\begingroup$ What about that photo suggests to you that there's no dust left? It looks like a pretty normal mix of regolith and dust to me... (That said, rockets in a vacuum spread out very quickly after leaving the bell, so it's not going to be nearly as much pressure to push stuff around as the same rocket on earth has.) $\endgroup$
    – Darth Pseudonym
    Commented Aug 24, 2023 at 15:13

0

Reset to default

Browse other questions tagged or ask your own question.