For most of human history, the universe was considered timeless and unchanging; no longer. At the Space Telescope Science Institute, on the Johns Hopkins University campus, a constant torrent of data pours in from NASA’s James Webb Space Telescope. Launched 13 months ago, Webb is orbiting 940,000 miles above the earth. George Will writes, “With its 18 mirrors and its five sunshield layers unfolded, it is a tennis-court-size engineering masterpiece. To function, each mirror must, after being hurled into space on a shuddering rocket, retain this exquisite precision: If each mirror were the size of the continental United States, each should not vary more than 2 inches from perfect conformity with the others. Furthermore, the mirrors left Earth the ‘wrong’ size: They were designed to contract in space to achieve a precise shape at the temperature out there: minus-388 degrees Fahrenheit. The wavelength of light is ‘stretched’ as the universe expands; hence the analysis of light can date the light’s source.”
Jakarta, March 30, 2024, 14:18/18 Ramadhan, 1445 H.
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