Speed of Light; Age of Universe ```Name: Gary Status: other Grade: other Location: NV Country: N/A Date: N/A ``` Question: When viewing Hubble deep field images on the Internet, we are told we are looking at how the objects looked at that time i.e. 12 billion years ago. Assuming nothing can exceed the speed of light, including the expanding universe, how can we see light from 12 billion years ago if we are moving away from the big bang slower than the light we are looking at? Replies: Gary, If we took a look at a galaxy, say in January, and then again in June, we would be looking at that particular galaxy from two corners of a triangle (with the galaxy forming the last point of the triangle), and have the longest possible edge length between the measuring points (since the Earth will have moved between the farthest points of its orbit around the Sun). Using the angle of sighting, we can then triangulate the distance of that particular galaxy. We can estimate the distance of that galaxy from the Earth. If we then find that the galaxy is so far such that it would take 12 billion years for the light of that galaxy to reach us, then we have to accept that whatever information the light that is currently reaching us contains -must be 12 billion years old. Greg (Roberto Gregorius) Click here to return to the Astronomy Archives

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