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

"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,…
"One mustn't look at the abyss, because there is at the bottom an inexpressible charm which attracts us." -Gustave Flaubert The deepest depths of space, out beyond our atmosphere, our Solar System, and even our galaxy, hold the richness of the great Universe beyond. Stretching for billions of light…
"You may hate gravity, but gravity doesn't care." -Clayton Christensen What's the deal with gravity, dark matter, and this whole "lensing" business anyway? You've probably heard that energy -- most commonly mass -- bends light. And perhaps you've seen an image or two like this one to illustrate…
"The best way to escape from a problem is to solve it." -Alan Saporta One of the greatest puzzles in the Universe today is just why the Universe is structured the way it is. Image credit: Robert Gendler / Hubble Legacy Archive. For the individual galaxies that we see, the puzzle is why they…

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