Which of the following techniques have now produced the sharpest images of sources in the universe?
A.the combination of many radio telescopes into an interferometer
B.the electronic imaging on the new 10-meter-diameter Keck telescope on the high volcanic mountain, Mauna Kea, on Hawaii
C.CCD photography with cameras on board the 2.4-meter Hubble Space Telescope from above the atmosphere, in space
D.imaging using X-ray telescopes in space, such as NASA's Chandra X-ray Observatory
A.the combination of many radio telescopes into an interferometer
B.the electronic imaging on the new 10-meter-diameter Keck telescope on the high volcanic mountain, Mauna Kea, on Hawaii
C.CCD photography with cameras on board the 2.4-meter Hubble Space Telescope from above the atmosphere, in space
D.imaging using X-ray telescopes in space, such as NASA's Chandra X-ray Observatory