A scientist uses a telescope to observe the two stars. Which of these is the best conclusion about the images of the two stars a
s seen by the scientist? A: The images show the stars as they existed 7 years ago. B: The images show the stars as they existed 15 years ago. C: The image of 61 Cygni is more recent than the image of Proxima Centauri. D: The image of Proxima Centauri is more recent than the image of 61 Cygni.
Astronomers use NASA's Spitzer Infrared Telescope and Chandra X-ray Observatory to see young stars, which emit a lot more high-energy radiation than their older versions.
