How long would it take to travel to the new planet?
The Sunday Nation
Nairobi,
11 December 2011
Astronomers have recently announced the discovery of a planet that appears to be a likely candidate for life outside the Earth. But before you get all excited about the news, it important to not that this “new world” is 600 light years away.
As the name implies, it takes a beam of light 600 years to travel from the Earth to this planet. Now the speed of light is 300,000 kilometres per second. This is much faster than any rocket that has ever been build. The cruising speed of Space Shuttle, for example was about 30,000km/h during re-entry into the Earth’s atmosphere.
At first sight, 30,000km/h looks quite high, but not so when it is converted to km/s. Since one hour has 60 minutes and one minute has 60 seconds, it is easy to see that one hour has 3,600 seconds (60 x 60).
Therefore to convert any speed from km/h to km/s, we must divide it by 3,600. Thus, 30,000km/h is equal to 8.33km/sec. Compared to light, the Space Shuttle is slower than a snail! If we were to use it to travel to the new planet, the journey would take about 21 million years!
But millions of years are difficult to conceptualise and the Space Shuttle is not the fastest craft ever built. That record is held by Voyager 1, the NASA outer solar system explorer launched in 1977. There were actually two identical spacecrafts, Voyager 1 and Voyager 2 launched only two weeks apart.
Currently, the two crafts are 18 billion and 14 billion kilometres away and cruising at 17.3km/s and 15.5km/s respectively. That’s very far and very fast: both Voyagers have gone way past the outer extremes of Pluto’s orbit.
But their journey brings out the great challenge of space travel: 34 years later, the spacecrafts are still within the known solar system…and they are the fastest man-made objects in the universe! At current speeds, they will cover one light year in about 14,000 years and about 30,000 years to get out of the solar system. So how would they take to travel 600 light years? Well, you work it out!
Clearly, distances between stars are so vast that they cannot be covered in a normal human lifetime. Unless, of course some one figures out a way of getting from point A to point B without traversing the distance.
One theory says that we could try to create so-called “wormholes” in the space-time continuum. To understand the idea, imagine that there is a worm crawling on the outer surface of an apple. If the worm wanted to travel from one side of the fruit to the next, it has two choices.
It can crawl along the curved surface – a
long but easy journey – or it can eat a hole in the apple, through the
centre and out the other side – a short but difficult route. There are
those who think that the same CAN be done in space-time. This would have
two important results: much quicker transits through space and the
ability to travel through time. But first, we would have to “bend” it
and so far, no one knows how to do that.
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