Space (2019 | Issue 1)

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We are all drawn to exploration. To go beyond the familiar is a natural inclination. Beyond our neighbourhoods, cities, countries and, for a select few, further on. We’ve all looked up at the night sky wondering what lies out there and what our place is in the universe. What’s Up, Germany? focuses the telescope on the infinite space around our Earth.

The sheer vastness of the universe is staggering. It contains everything that exists: All of space and time, including the planets, stars, galaxies and other forms of matter and energy. No one knows how big the universe is. We cannot see its edge—if there is one! What we do know is that the visible universe is about 92 billion light-years across. (A light-year is the distance light travels in one year, which is roughly 9.5 trillion kilometres.) We believe the universe was born with the Big Bang more than 13 billion years ago when there was a massive expansion of space.

Our Little Blue Planet

The Earth is part of the Milky Way, a spiral-shaped galaxy that contains the solar system and hundreds of billions of stars and planets. Traveling at the speed of light, it would take a spaceship 100,000 years to cross the Milky Way! And that’s just the size of our cosmic neighbourhood! The rest of the universe is unimaginably large.

There are at least two trillion galaxies in the observable universe. Can you imagine the size of it?! Now you might conclude that the universe is densely packed, but that’s not the case. Most of it is empty space. Ninety-five percent consists of dark matter and dark energy. The planets, stars and galaxies make up just five percent of the universe.

Out of this World!

For us earthlings, outer space officially begins at the invisible Kármán line, which is 100 kilometres above sea level. It is the void that exists beyond the Earth and between celestial bodies. This void is not devoid of matter though; it contains huge amounts of thinly spread gas and dust. Since there is no air to scatter sunlight nor any sound waves, space looks like a black blanket covered with stars and is completely silent.