Space and related Trivia Flashcards
What is the actual color of the sun, why does it appear yellow, and related to this why is the sky blue?
The sun is so hot, and when something is very very hot its color becomes white – so the actual color of the sun is white. Astronauts have verified this, they have looked at the sun from space and and see the sun as white in color.
When suns white light travels through the miles of earths atmosphere the atmosphere causes diffusion of the suns white light. This difiusion happens in such a way that the violet and blue components of the suns light get dispersed in the atmosphere and the remaining components of the light specturm which add up to the yellow color make it down to earths surface and that is why we see the color of the sun as yellow – becuase of the selective diffusion of the light as it travels through the atmosphere
For the same reason of diffusion, the blue and violet spectrum that is filtered in the atmosphere makes the sky appear blue to us. If we did not have an atmosphere there would be no diffusion and the sun would appear white in color, and the sky would appear black – just as the sky appears black when seen from the moon, which does not have an atmosphere
What is the concept of multiple universe’s?
The universe as we understand it is everything that was formed as a result of the big bang that occured some 14.5 billion years ago – our star the sun, our solar system, our galaxy, and all other galaxy’s, black holes, etc were born out of this big bang and that is our known universe.
But imagine that there were other big bangs of the same kind that have similarly created their own universe – that is how the concept of more than one universe comes about. In other words – there can be multiverse. The only reason we do not see those other universe is because they are so far away that their light is somehow not able to make it to us – not a perfectly clear explanation…but something to be developed further.
What are some of the interesting distances in space
Earth is about 100 million miles from the sun. It takes about 8 minutes for the light to travel that distance from the sun to earth
Mercury is about 33 million miles from the sun
Jupiter is about 600 million miles from the sun
Our moon is about 250 thousand miles from the earth (1/4th of a million mile – if talking in terms of millions of miles that seems to be the right unit for Space related distances)
What is the concept of the Sun becoming larger and its implication for life on Earth?
It is believed that (for some reasons) Sun’s size is expanding – it is becoming bigger. At some point it will be large enough to engulf Mercury, and then Venus, and eventually even Earth. As the Sun expands, earth will start becoming hotter (Sun will be bigger and closer to earth) and that high temperatures on earth will result in destruction of first basic life – plant life, followed by animal life, and mankind will be left with no food sources and even temperatures will be too high for mankinds living. Earth will become more like Venus is today. That is why many hundred million years from now, mankind will have to start looking to create earth like conditions on a distant planet – such as Mars.
Just like Columbus and other explorers colonized earth, similarly in future there will be new Columbus’s that will explore the Space and help with colonization of say, Mars and settling mankind over there.
This will all have to be done in about 600 million years time. Look for another question to fully understand this timeline.
The expansion of Sun will result in earth becoming un-inhabitable for life. What is the timeline associated with this?
It is believed that mankind has about 600 million years before the conditions on earth will become too hot for survival (due to the expansion of the Sun). To put this in context, it was about 65 million years ago that Dinosaur’s lived on earth and became extinct. So the time available to mankind is about 10 times of since the Dinosaurs became extinct. Further, it was about 250 thousand years ago when the first human-like creatures began to evolve from the Apes. It was about 100 thousand years ago that mankind that resembles us evolved. It was only about 20,000 years that mankind started to sow the seeds from which our culture started to evolve. It was only about 10,000 years ago that mankind started settling down by river banks and living in communities. The Egyptian civilization started about 5000 years ago.
How can you make vast amounts of time such as 14.5 billion years ago that the universe was created and make it more comprehensible
By compressing that time of 14.5 billion years ago onto a scale of 1 year – a scale that you can related to.
When you divide 14 billion years by the number of seconds in a year the number you get is how many years a second represents. Thus 14,000,000,000/365*24*60*60 = 444 or say 500 years – in other words 500 years corresponds to 1 sec.
Similarly, if the Egyptian civilization was formed 5000 years ago – that would be just 10 seconds ago.
Human beings evolved some 100,000 years ago which is about 200 seconds or 3 minutes ago
Dinosaurs ruled the earth some 60 million years ago which is about 3*10*60 = 1800 minutes = 30 hours or about 1.2 days ago
What is the relative size of the Sun, Earth our solar system in the Universe
If you imagine the Universe to be a gian sphere that is expanding outwards at lightining speed as a result of the big bang, our solar system would just be a tiny speck near one of the outer edges of this sphere. So we think of our solar system as really vast even the moon so far away from us, but on a galactic scale it is all very tiny and our solar system is just a speck.
