If you had the power to look back in time and see events before they happened how much would you pay for this gift? The price has a broad range believe it or not. Anywhere from free, all the way up to a cost of around 6.5 billion dollars.
When you look up into the night sky, it doesn’t cost you anything and you are also looking into the past at the same time.Many of the stars that you see when you look into the sky are not even there anymore or are at least in a different from now. See It comes down to the great distances that the light has to travel in order to reach us for us to “see” it.
Let’s use the sun as an example. When you look up at that great ball of fire in the sky, it has taken that light roughly seven minutes to reach us. So when you see the sun, you are actually looking at how the sun looked over seven minutes ago. So let us imagine tomorrow at exactly 1pm, the sun explodes and is with us no more. With only the aid of our eyes we would not actually see the explosion until around 1:07 pm when the light from the event actually reached us.
The stars we see at night are so much farther away that in many cases it has taken hundreds of thousands, if not millions of years for their light to reach us. So many of the stars we see may not even be there anymore. Yet the light from their previous existence continues to travel toward earth so we can still see them.
This is one reason why telescopes such as the Hubble and the James Webb Telescope (the possible future replacement of the Hubble) are so important to us, They provide a window into the past giving great clues into just how our universe was formed. The stronger the telescope, the farther back in time we can look.
Due to cutbacks in the NASA budget, the newer James Webb Telescope is in danger of never seeing the light of day despite the budget of the telescope already exceeding 6.5 billion dollars. I am aware at first glance this sounds like a lot and in fact it is. But keep in mind that the Hubble Telescope has cost right at 6 billion dollars to this date and that equates to just over 250 million dollars a year in the 20 plus years it’s been in service.
It is also a drop in the bucket when you consider that each shuttle launch costs around 450 million dollars, and also given the fact that the shuttle fleet has now been grounded, NASA will now be paying Russia over 500 million dollars for each trip to the international space station.
When you think about the benefits that these telescopes can offer, it would be a shame to see the end of support for the Hubble in the next few years and see the Webb Telescope scrapped due to budget concerns. Given the amazing amount of knowledge we have gained from the Hubble, the Webb Telescope, which is purported to be 100 times more powerful, would give a view of our universe that would be simply unimaginable.
So remember next time your outside, take a look up at the night sky. While time travel may not be possible, it is possible to take a look back in time. All from the comfort of your back porch and hopefully a little help from NASA.
Sources: space.com