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Reading this question and then this report in a comment by @called2voyage

At some point they talk about possibility to send (using antimatter as propellant) a space mission to solar gravity lens focus, using it as a giant telescope to observe exoplanets.

Since this solar focus is quite far ( 550 UA )

Is gravitational light bending capability of the earth enough to think of a smaller mission to earth gravity lens focus? How far would this focus be? And how magnifying this virtual lens would be? What about other planets focii in the solar system?

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    $\begingroup$ A lens being smaller does not equal the focus being closer. $\endgroup$ – jkavalik Nov 11 '17 at 12:48
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    $\begingroup$ Dr. Claudio Maccone has put some thought into these ideas. If I remember it correctly the focus of Jupiter's gravitational lens is about 10 times further away than the Sun's. And for Earth it's something like 30 times further away. I suppose the pointing challenge and other things get worse with distance. And anti-matter isn't required to send something 550 AU away, given patience and good engineering. $\endgroup$ – LocalFluff Nov 11 '17 at 14:43
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    $\begingroup$ Here's a table by Maccone on using planets as gravitational lenses: youtu.be/iB6d27oLAnc?t=435 $\endgroup$ – LocalFluff Nov 11 '17 at 15:00
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    $\begingroup$ A planet as a gravitational lens at least has the advantage of getting rid of the Sun's corona. $\endgroup$ – LocalFluff Nov 11 '17 at 15:27
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    $\begingroup$ Interesting. Didn't see any dependence from body's density coming. Very strange to see that Earth has better optical power than Uranus. $\endgroup$ – ZuOverture Nov 11 '17 at 17:45

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