Space is Big
“Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.” Douglas Adams – Hitchhikers Guide to the Galaxy.
Space really is big and it is difficult to give perspective to many of the deep space objects shown. Not only are they big, they are also a long way from earth.
Astronomical distances are measured in Light Years, that is the distance that light travels in one year.
Light travels at 186,282 miles per second, so in one year it travels around 6 Trillion miles (6,000,000,000,000 miles).
Many of the objects featured on this site are thousands of light years from earth and, despite this, when viewed from earth they can take up more of the sky than a full moon.
For example , the Heart Nebula takes up the same space in our night sky as 25 full moons but is 7,500 light years away – that is 7,500 x 6,000,000,000,000 Miles – almost beyond comprehension!
Time Travel
The vast distances of deep space objects from earth means the light we see from them today left those objects many, perhaps thousands or millions, of years ago. If an object is 1,000 light years away we are actually seeing what it looked like 1,000 years ago.
Some of the objects photographed may actually have changed significantly since the light we now see left them, for example some stars may already have become supernovae yet it may be thousands of years before the light from the explosion reaches earth and future generations will be able to see there demise.
Facts and Figures Disclaimer
All of the measurements of size and distances used are estimates and in many cases the “expert” opinions will differ and change over time. I have used currently available estimates but do contact me if you have more accurate information.