California, Jan. 13 (BUS): NASA on Wednesday embarked on the grueling, months-long process of putting the newly launched James Webb Space Telescope into focus, a mission that is set to be completed in time for the revolutionary eye to begin in the sky. in the universe by early summer.
Mission control engineers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, begin sending their initial commands to tiny actuators called actuators that slowly set and adjust the telescope’s main mirror.
The primary mirror is made of 18 hexagonal pieces of gold-plated beryllium metal, and measures 21 feet 4 inches (6.5 m) in diameter — a light-gathering surface much larger than its predecessor Webb, the 30-year-old Hubble Space Telescope.
Folded together to fit the cargo bay of the rocket that carried the telescope into space, the eighteen sections were folded together with the rest of its structural components during the two-week period after Webb’s December 25 launch.
These sections must now be separated from the fasteners that hold them in place for release and then move forward half an inch from their original formation – a 10-day process – before they are aligned to form a single uninterrupted light-gathering surface.
The alignment will take an additional three months, said Lee Feinberg, Goddard’s Webb optical telescope element manager.
Aligning the primary mirror segments to form one large mirror, Feinberg said, means that each segment is “in line with one-fifth of the thickness of a human hair.”
“All of this requires us to invent things that have not been done before,” he added, such as engines that are designed to move incrementally at -400 Fahrenheit (-240 Celsius) in the vacuum of space.
The telescope’s small secondary mirror, which is designed to direct the light collected from the primary lens to a webcam and other instruments, must also be aligned to function as part of a coherent optical system.
If all goes as planned, Feinberg said, the telescope should be ready to take its first science images in May, which will be processed over another month before being released to the public.
The $9 billion telescope, billed by NASA as the premier space science observatory of the next decade, will essentially display the universe in the infrared spectrum, allowing it to peer through the clouds of gas and dust where stars are born. Hubble worked primarily at optical and ultraviolet wavelengths.
Webb is about 100 times more powerful than Hubble, enabling it to observe objects at greater distances and, therefore, in the past, than Hubble or any other telescope.
Astronomers say this will offer a glimpse into the universe never seen before — dating back only 100 million years after the Big Bang, the theoretical flashpoint that led to the expansion of the visible universe an estimated 13.8 billion years ago.
The telescope is an international collaboration led by NASA in partnership with the European and Canadian space agencies. Northrop Grumman was the prime contractor.
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