Move Over, Hubble: Gravity Itself Is The Best Cosmic Telescope Of All (Synopsis)

"Gravitational and electromagnetic interactions are long-range interactions, meaning they act on objects no matter how far they are separated from each other." -Francois Englert

Want a recipe for seeing as far into the distant Universe as you can? Because of how distance and brightness are inversely related, you need to make the most of every photon, build as large a telescope as possible and observe for long periods of time in order to collect the most light.

Image credit: NASA/ESA, of an illustration of how gravitational lensing works. Image credit: XMM-Newton, ESA, NASA.

But there's an extra bit of magnification that Einstein's General Relativity gives to us for free: gravitational lensing, where any large mass magnifies the light from the objects directly behind it. Thanks to this technique, we've discovered the most distant galaxies ever.

Image credit: NASA, ESA, R. Bouwens and G. Illingsworth (UC Santa Cruz). Image credit: XMM-Newton, ESA, NASA.

Starts With A Bang begins on Forbes today; come check out our debut piece!

More like this

"Not only does God play dice, but... he sometimes throws them where they cannot be seen." -Stephen Hawking The New York Times ran an article on Stephen Hawking promising there was a possible escape route from a black hole, after all. In the text, Hawking asserts, "They are not the eternal prisons…
“End? No, the journey doesn’t end here. Death is just another path, one that we all must take. The grey rain-curtain of this world rolls back, and all turns to silver glass, and then you see it.” -J.R.R. Tolkien There's a realization we all face at some point in our lives: that not only are we…
"Gravitational and electromagnetic interactions are long-range interactions, meaning they act on objects no matter how far they are separated from each other." -Francois Englert One of the most spectacular predictions of Einstein's General Relativity was the existence of gravitational lensing,…
"The first amazing fact about gravitation is that the ratio of inertial mass to gravitational mass is constant wherever we have checked it. The second amazing thing about gravitation is how weak it is." -Richard Feynman One of the strangest, most novel predictions of Einstein's relativity is that…

Ethan, I was hoping this post might say something about the plausibility of using our sun as a gravitational lens, and sending a telescope far enough away to make it work (iirc the distance required is on the order of 1/100th of a light year). Of course you only get to point it at one target, aligned with your trajectory... Is it a crackpot idea, or will we probably do this one day?

By wrathOfShereKhan (not verified) on 10 Nov 2015 #permalink