In this photograph released last week, NASA engineer Ernie Wright stands in front of six mirror segments as they are being prepped for cryogenic testing at NASA's Marshall Space Flight Center. The six segments will eventually join a dozen more to form the primary mirror for observations on the James Webb Space Telescope. "Engineers began final round-the-clock cryogenic testing to confirm that the mirrors will respond as expected to the extreme temperatures of space prior to integration into the telescope's permanent housing structure," according to NASA's official website.
View more Pictures of the Day.
We want to hear what you think about this article. Submit a letter to the editor or write to email@example.com.