Story Time: Advancing the frontiers of knowledgeMagazines
For some time now, we have delved into the stories of the masters of the past. No longer are Galileo, Kepler, Newton, Herschel or Einstein strange or alien names for us. It is another matter that we have not probed the above-named individuals’ work in detail. But rest assured, we shall delve into their achievements more comprehensively as opportunity presents itself.
But first: the remaining part of the last Ice Age, discussed in the recent past.
The most intriguing aspect of this great period is the wall paintings pertaining to Ice Age that have been discovered at more than a dozen places in caves around the world, notably in Spain, France, Morocco and some other parts of the world. These have been chemically tested and found to be 20,000 to 30,000 years old, meaning that some were drawn by people bang in the middle of the last Ice Age! Some others pertain to the period when the Ice Age was drawing to a close, some 12,000 years back. Both details are remarkable.
This is enough to substantiate two facts. One, men and women, pretty advanced in culture and imagination, existed then and had been around for many thousands of years to have attained such a high degree of advancement. And two, that paint technology had run up a high position, perhaps not attained in other aspects of life such as house-building and city-dwelling.
Great migrations were taking place, irrespective of the prevailing Ice Age, such as the peopling of the Americas by the peoples of the Asiatic steppes. Or the migration of Australia’s Aborigines into that country or away from it. It goes also to prove that humans were always a hardy and determined species, not bogged down by impediments such as bitter cold or the intervening seas. During the Ice Age, and somewhat later, the seas provided humans with land bridges, making travel easier.
Now back to the parlance.
Jupiter: The fifth planet out from the Sun, it is also the largest of them all — more massive than all the planets put together. It has been known to be so since ancient times.
It has a faint ring system. In fact, all four Jovian planets (Jupiter, Saturn, Uranus and Neptune) have a ring system each. Jupiter’s was only discovered by Voyager1 (in 1979). We know that Galileo trained the newly-invented telescope at Jupiter in 1610 and discovered the four moons in its close proximity. Galileo’s discoveries, particularly of the Earth revolving around the Sun, came much to the annoyance of the Church which believed it was the other way round. As a result, the dreaded Inquisition went right after him. Only his old age came to his rescue.
Jupiter is massive by any standard:
It contains 71 percent of all planetary matter of our solar system.
It contains 317.83 times more mass than the Earth. Its diameter is 11 times that of the Earth’s.
The pressure of hydrogen is so great that it is regarded as a liquid planet, which is proved by its plastic surface.
Its rapid rotation takes only nine hours 50 minutes and 30 seconds. Comparing the Earth with Jupiter on its rotation alone will show that it rotates more than twice the rate of the Earth.
Due to its gases, it is not a perfect ball but oblate. A great ball of gases, it still has an Earth-like core, that is, rocks and metals.
The interior pressure is 300 million times the pressure of the Earth’s atmosphere. That is, sort of crazy! Enough to crush an elephant to cinder instantly.
It might be as hot as 30,000K at its centre. Just a little lower than incandescence, which would turn it into a star.
With such remarkable statistics, Jupiter might well have become a small star. In many ways it rivals the sun, (or a star) following a star’s eminence.
Jupiter’s average distance from the sun is 5.23 AUs (Earth’s is 1AU, as you know). It goes around the Sun at over 13 km/sec, and takes 11.87 years to go around the sun once. Its equatorial diameter, 143,800 km, is massive, and the gravity means that its escape velocity is 61 km/sec. Earth’s is 12,756km and 11.2 km/sec respectively.
Jupiter has some 25 moons, some of them too small to be classified as moons; I’d rather call them asteroids wrested from the belt. They are rocky and uneven, a few measly kilometres across, revelling in prominent company. It is often cited to have more moons. So much for Jupiter for now.
Published in Dawn, Young World, January 28th, 2017, 2016