NASA's Plan To Block Light From Distant Stars To Find 'Earth 2.0' 92
Daniel_Stuckey (2647775) writes "Over the last five years, NASA's Kepler Space Telescope has found dozens of potentially habitable planets. The only problem is that we can't actually see them, because the glare from those planets' stars makes it impossible to image them directly. A new, audacious plan to completely block out the light from those stars, however, could change all of that. The plan calls for a satellite to be sent out several tens of thousands of miles from Earth. The satellite will unfold a huge, flower-shaped metal shade that will literally block the light of some far-out star to the point where a space telescope, which will directly communicate with Starshade, will be able to image whatever planets are orbiting it directly. It's called Starshade, and, given the name, it works exactly how you might expect it to. If you look directly at the sun, you're not going to be able to see anything in the sky around it. Hold up something between your eyes and the sun to block it, however, and you'll be able to see much better."
Re: Can they make a 3D shade? (Score:4, Insightful)
The petals are to deal with diffraction issues. If you had just a circle, the diffraction pattern is such that you get a small bright spot [wikipedia.org] in the center of the area behind the circular obstruction, which would basically counteract what the obscurer is trying to do. This would make something like a sphere rather difficult since you need to get the shape right, otherwise diffraction will still dump a lot of the star's light on the center of the telescope.