Is there a limit?

[pioneer0333]

Is there a limit on how far we can see with a telescope?<br /> And if there is, who are we to say that there is nothing beyond that of which we can see? Finally, how strong is the strongest telescope that is in use presently? <div class="Discussion_UserSignature"> </div>

 

[newtonian]

Pioneer0333 - Yes, but....<br /><br />For light telescopes [as in electromagnetic radiation, not lack of weight], the limit is the speed of light.<br /><br />This is equally true for visible light as ii is for microwave, infrared, x-ray, gamma-ray, etc.<br /><br />The limit then becomes time, i.e. how old is light, or electromagnetic radiation.<br /><br />Thus one could say, at least for our universe, this limit might be 100,000 years after the big bang.<br /><br />Then, of course, we need to date the big bang.<br /><br />Which is mostly done by telescope, i.e. spectral analysis, red shift effects, etc.<br /><br />There is, of course, a degree of circular reasoning in these estimates - but they generally are about 10 - 20 billion years ago [more precisely 12-15 billion years ago, current popular estimates].<br /><br />Hence 10-20 billion light years away for distance limit.<br /><br />Note that the universe was opaque before becoming transparent.<br /><br />And, of course, the possibility that there are forms of energy penetrating our universe from another universe.<br /><br />Which is why I started my thread on dark energy telescopes. [dark energy could be from outside the system, making our universe an open system - which is opposite the assumptions of most astronomers, btw.]<br /><br />If dark energy travels faster than c (c=the speed of light), then dark energy telescopes could vastly extend our visibility horizon far beyond current limits.<br /><br />First, though, we must find a detector surface for observing dark energy!

 

[mpai]

Newtonian is to the point with the reply "Hence 10-20 billion light years away for distance limit. "<br /><br />You might like to the check Phil Plait's Bad Astronomy link on the subject here<br /><br />http://www.badastronomy.com/bitesize/howfar.html<br /><br />Clear skies<br />