Editing Space settlement (section)

===Meteoroids and dust===
The habitat would need to withstand potential impacts from [[space debris]], [[meteoroid]]s, dust,&nbsp;etc. Most meteoroids that strike the earth vaporize in the atmosphere. Without a thick protective atmosphere meteoroid strikes would pose a much greater risk to a space settlement. [[Radar]] will sweep the space around each habitat mapping the trajectory of debris and other man-made objects and allowing corrective actions to be taken to protect the habitat.{{citation needed|date=September 2012}}<!-- on what basis is this claim made? "will sweep ..." and "allowing corrective action...". Even in low-Earth orbit, these orbital speeds are thousands of meters per second, and there is no source to show that large habitats might easily avoid them with radar. -->

In some designs (O'Neill/NASA Ames "Stanford Torus" and "Crystal palace in a Hatbox" habitat designs have a non-rotating cosmic ray shield of packed sand (~1.9 m thick) or even artificial aggregate rock (1.7 m ersatz concrete). Other proposals use the rock as structure and integral shielding (O'Neill, "the High Frontier". Sheppard, "Concrete Space Colonies"; Spaceflight, journal of the B.I.S.) In any of these cases, strong meteoroid protection is implied by the external radiation shell ~4.5 tonnes of rock material, per square meter.<ref>{{cite web| url=http://www.quadibloc.com/science/spaint.htm | title=A Space Habitat Design | website=quadibloc.com | date= | access-date= 8 February 2021 }}</ref>

Note that Solar Power Satellites are proposed in the multi-GW ranges, and such energies and technologies would allow constant radar mapping of nearby 3D space out-to arbitrarily far away, limited only by effort expended to do so.

Proposals are available to move even kilometer-sized NEOs to high Earth orbits, and reaction engines for such purposes would move a space settlement and any arbitrarily large shield, but not in any timely or rapid manner, the thrust being very low compared to the huge mass.