Philosophical musing for today (something I learned from Sophie’s World by Jostein Gaarder):
Did you know that when you look at the stars in the sky, you are actually looking back in time? The universe is vast beyond comprehension and the distance between the earth and the stars is so great, they are measured in light-minutes and light-years. A light-minute is the measurement of the distance light travels in one minute. Light travels through space at 300,000 kilometers a second. A light-minute, therefore, is 18 million kilometers. One light-year is approximately around ten trillion kilometers.
The furthest planet away from earth in the solar system is Pluto, around 5 light-hours away from us. So when you look at Pluto through a telescope, you are actually looking five hours back in time.
The entire Milky Way is 90,000 light-years wide. So when we gaze at a star in our galaxy, 50,000 light years away from the sun, we are looking back 50,00 years in time. Beyond our galaxy, there are a hundred billion stars. The nearest galaxy to ours, the Andromeda nebula, is two million light-years away. That means the light from that galaxy takes two million years to reach us. So we’re actually looking back in time when we see the Andromeda nebula in the sky.
And apparently, no galaxy in space remains where it is. All galaxies in the universe move further away from each other at incredible speeds. The further they are away from us, the faster they move. The universe has no geography. So when astronomers pick up light from galaxies billions of light-years away, they are actually charting the universe as it looked during the Big Bang. Everything we see in the sky is cosmic fossil from millions of years ago. And that is why I no longer believe in astrology. All it does is predict the past.
