View Full Version : Astronomers Use Light Echos to Measure the Distance to a Star

2008-Feb-12, 12:10 AM
Because stars are just points of light in the sky, it's very difficult to know how far away they are. Astronomers use several techniques to measure distance, but they've got a new one now. By measuring echos of light bouncing off a distant nebula, researchers have fine-tuned their accuracy to an amazing level of precision.

More... (http://www.universetoday.com/2008/02/11/astronomers-use-light-echos-to-measure-the-distance-to-a-star/)

2008-Feb-12, 05:44 PM
The video link in this story is *very* cool. You can see 41 day separated pulses radiating through and out of the cloud. This is great to see. It is also nice to have a new tool to nail down this key element of the distance ladder a little more tightly.

2008-Feb-12, 09:23 PM
That's a pretty neat idea.

2008-Feb-12, 10:16 PM
I remember pictures a few years ago showing
disturbances in the Crab Nebula emanating
from the central pulsar. The same principles
must have improved the distance estimates to
the object by an order of magnitude. Dont
remember any song and dance about it though!