Three planets orbit the star HR 8799, as revealed by this infrared image. Hawaii’s Keck and Gemini North telescopes zeroed in on the young planets’ heat signatures to create the first group portrait of another solar system.
Christian Marois/National Research Council Canada
aliens could image Venus, Earth, Jupiter, and Saturn. The scientists could also track the planets’ orbits and collect spectroscopic data that would reveal Earth’s water and oxygen as well as carbon dioxide on Venus and methane on Jupiter and Saturn.
