Take a small denomination copper coin – a US or UK penny does fine for this circumstance.

Hold it at the furthest arm’s length that you possibly can, stretch really far, and imagine it polished-up to a bright, vomitous pink colour, the fleshy pink of a common “Band Aid” or other surgical item.

Imagine the face of the dead President or live Queen to be slightly dirtied by oxidation or verdigris.

Now imagine that someone has let drop the smallest drop of brilliant white paint fall upon the topmost rim of the coin, and that you are viewing the whole through a yard’s depth of swimming pool, the water making the coin swirl and shimmer against a backdrop that is as grey-green and dull as a unplugged television set’s screen.

Oh yes: and imagine that you are freezing, and yet feel like you are having perverse fun.

That, approximately, is what it is like to observe mars at 100x magnification from the British Isles.