Mass and Weight. What's the Difference?

British spelling!

Here are two of my short stories, I hope you find them interesting and educational.

<><><>

1/2

Mass and weight, what's the difference?

Mass

Imagine a steel ball. Now send the ball to the moon, Mars, or even far out into space, and its mass would stay the same. The mass of an object never changes, no matter where it is in the universe.

I will say this before someone corrects me! Add or subtract steel from the ball, and of course, its mass would change.

Weight.

The weight of an object is due to its mass and the force of gravity acting on it.

The gravitational force of the Earth is trying to pull me down to its centre, so when I stand on my weighing scales here on Earth, it registers at 80 kilograms.

If I went to the moon and stood on my scales there, it would register at 13 kilograms.

The reason I am being pulled down with less force on the moon is that it has less mass than the Earth and, therefore less gravity. On Mars, I would weigh a little over 30 kilograms.

The largest, by far, of the eight planets in our solar system is the gas giant Jupiter. It would be impossible to stand on Jupiter as it has no solid surface, but if it was possible, my weight on Jupiter would be just over 202 kilograms.

Not including a black hole, a neutron star has the highest gravitation force of any known celestial object in the universe. If it were possible to stand on its surface, my weight would be an incredible 11,200,000,000,000 kilograms, that number is over 11 trillion.

I could say that I would weigh zero in deep space, but I would always be gravitationally attracted to something, albeit a very small attraction.

This is an interesting paragraph about gravity.

Imagine dropping a large rock and a feather from a high building, it would be no surprise when the rock makes contact with the ground first, air resistance will have slowed down the feather.

Now do the same experiment in a vacuum, no matter how high you drop the rock and feather they will both make contact with the ground at precisely the same time.

<> <> <>

2/2

Imagine the chaos if the sun disappeared.

Imagine what would happen if our local star the Sun just disappeared.

The Sun started shining about 4.6 billion years ago and will continue to do so for another 5 billion years or more. The sun is a ball of hot plasma heated by nuclear reactions in its core.

The sun is the most important source of energy for most of life on Earth. I say most because there is life in the ocean depths that doesn't depend directly on the sun.

Around hydrothermal vents deep in the ocean, microbes eat nutrient chemicals that form the base of the food chain for more complex communities of organisms.

If you have a good imagination, then you might find the next few paragraphs interesting.

Ok, so the sun just instantly disappeared; we would have no idea until just over eight minutes later when the sky turned black.

That eight minutes is the time it takes for light to travel 150 million kilometres which is the distance between the sun and our planet.

No more bright moon or planets; we are accustomed to seeing the moon and some of the planets shining in the night sky, but of course, the moon and planets have no light of their own; moonlight is just reflected sunlight.

As you know, the Sun is by far the most massive object in the Solar System; its gravitation force is the reason all the planets, dwarf planets, moons, and all the other celestial objects are in organised paths around it.

Gravity waves travel at the same speed as light, and now it gets interesting. Without the sun, its gravitational force will also have ceased. Gravity waves also take just over 8 minutes to reach our planet; this is when planet Earth is released from the sun's gravitational grip and speeds away in a straight line at 107,000 kilometres per hour.

Mercury and Venus are closer to the Sun, so they will have gone on their separate paths before the Earth escaped. The other five planets will continue to orbit in the same position for a little while longer.

Can you imagine the chaos throughout the solar system?

As the Earth cooled down and our oceans and lakes froze, life would eventually come to an end. But remember the communities of life around hydrothermal vents deep on the ocean floor; they may survive for a very long time.

Back to reality:

Primitive life on our planet can be traced back at least 3.5 billion years; that is how long evolution has taken for the human species to appear.

The universe holds an estimated two trillion galaxies; some of those galaxies will hold millions, and others will hold billions of stars with unimaginable amounts of planets.

Surely there must be other life in that gargantuan area we call the universe, or could we be so unique that we are indeed alone?

We may never get a definite answer to one of the most important questions we ask: "Are we alone in the universe?"

The end.

<><><>

You may find my easy-to-understand stories about the universe and life interesting and educational.

If you subscribe to me for free, you will see my latest stories. Regards.