Assertion: telescope's mirror | /r/HasAspect | collecting area
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text: The JWST has an expected mass about half of Hubble Space Telescope's, but its primary mirror (a 6.5 meter diameter, 21.3-foot gold-coated beryllium reflector) will have a collecting area about five times as large (25 m2 or 270 sq ft vs. 4.5 m2 or 48 sq ft).