Solar gravitational lens

Dithered illustration of Solar gravitational lens

The Sun's gravity bends light like a lens, bringing it to a focus at least 550 astronomical units away. A telescope there could map a planet around another star, but only one pixel at a time.

The Sun works as a lens: its gravity bends light from a distant world to a focus far beyond it. Those planning missions there call it the only practical way to get a detailed, many-pixel image of an Earth-like planet around another star. The focus begins at least 550 astronomical units from the Sun, and no spacecraft has travelled even half that far. There is no snapshot: a 1000x1000 image of a planet at Proxima Centauri builds up pixel by pixel over about 14 months.

  1. Fermi paradoxThe Fermi paradox: life elsewhere looks likely, yet the universe we observe looks empty. Enrico Fermi, whose name it carries, never published a word about it.
  2. Breakthrough StarshotBreakthrough Starshot is a plan to fly gram-sized probes to Alpha Centauri on sails pushed by lasers from Earth. It has since been put on hold, with about $4.5 million of $100 million spent.
  3. XenobotsXenobots are living machines built from frog embryo cells to shapes designed by AI. Set among loose cells, they shove them into piles that grow into new xenobots.