Text 20 b exploring our sun

Give a summary of the text.

(A.Clark. “Profiles of the Future”)

How close to the Sun could a man-carrying ship approach in safety? The answer to this question depends upon the skill of the refrigeration experts; my guess is that five million miles is an attainable distance even with a crew-carrying vehicle.

There is one useful trick we may employ to get quite close to the Sun in (almost) perfect safety. This is to use some asteroid or comet as a sunshade, and the best choice known at the moment is the little flying mountain named Icarus.

This minor planet travels on an orbit that every thirteen months brings it within a mere 17 million miles of the Sun.

Occasionally, it also passes quite close to Earth; it was within 4 million miles of us in 1968.

Though small in diameter (approximately one or two miles), Icarus casts a cone of shadow into space, and in the cold shelter of that shadow, a ship could travel safely around the Sun.

Small though it is, this minor planet must weigh about 10 billion tons.

There may be other asteroids that go even closer to the Sun, if there are not, we may undoubtedly one day make them do so by a nudge at the right point in the orbit.

It is interesting to consider how long the travel would take. Being a rather small star, the Sun is “only” three million miles in circumference. A satellite just outside its atmosphere would move about a million miles an hour, so would circle it every three hours.

Magneto-hydrodynamics is concerned with the handling of very hot gases in magnetic fields. Already it has enabled us to produce temperatures of tens of millions of degrees in the laboratory, and ultimately it may lead us to the limitless power from hydrogen fusion.

I suggest that, when we have acquired some real mastery of this infant science, it will also give us magnetic and electric shields that can provide far more effective protection against both temperature and pressure that can be obtained from any walls of metal.

guess — припущення

cast a cone of shadow — відкидати тінь у вигляді конуса

nudge — поштовх

circumference — коло