The Speed of Light and Telespcopes

If scientists base themselves on the speed of light to calculate the distance of a distant planet, could this mean that if they find a new planet what they observe is exactly x lightyears old.

Everything we see is X light-years old, even things near us.

When we look at the Sun we see it as it was some 8 minutes ago.

And the scientists use other systems to calculate the distances, they could only use the speed of light if they knew the time that the light from a distant planet had taken to reach us.


PS: I think you should have posted this in a different forum, this has nothing to do with Aliens and/or UFOs, at least at the momment.

Not x lightyears old, x years old. A light year is a measurement of distance, as in how far light can travel in x years. To answer your question, take for example the recent discovery of a Earth type planet 20 lightyears away. The astronomers are seeing it as it was 20 years ago. When you look up to the Sun (Sol), you are seeing it as it was 8.3 minutes ago. When you look at the moon, you are seeing it as it was 1.25 seconds ago.

Originally posted by 10538
Not x lightyears old, x years old.

You are right, I also said "light-years old" when it should have been "years old".