Meet NASA’s
James Webb Space Telescope
Successor to the Hubble – Launch Date: 2018
By Mike Killian
In a 1.3 million cubic-foot cleanroom at NASA’s
Goddard Spaceflight Center in Greenbelt, Md.,
18 gold-coated primary mirror segments await
installation on NASA’s James Webb Space
Telescope. Those mirrors and the telescope’s four
science instruments just steps away, will become
the most powerful space telescope ever built.
“The Hubble Space Telescope has already
rewritten the science books. Going from Hubble
to the James Webb Space Telescope is like going
from a biplane to the jet engine,” said Maryland
Senator and Chairwoman of the Senate
Appropriations Committee Barbara Mikulski at
a news conference held at Goddard on Feb. 3.
“The James Webb Space Telescope will keep us
in the lead for astronomy for decades to come,
spurring the innovation and technology that keep
America’s economy rolling.”
With most of the major hardware now under
one roof, assembly of the massive space-based
observatory is expected to begin as soon as the
telescope’s structure arrives at Goddard, with
assembly expected to be completed in 2016.
This image shows the four types of mirrors on the Webb telescope: a
primary mirror segment, the secondary mirror, tertiary mirror and the
fine steering mirror. On the bottom row are the three different mirror
segments seen from the rear to illustrate the honeycomb structure
that makes the mirrors both very light and mechanically stiff.
Image NASA/Ball Aerospace/Tinsley
An artist’s impression of the James Webb Space Telescope.
Image: Northrop Grumman
Once complete, Webb – with its 69.5 ft x 46.5 ft
instruments-protecting sunshield deployed – will
be the size of a Boeing 737 airplane. Hubble, in
comparison, is about the size of a large tractortrailer truck or bus.
Webb’s 6.5-meter diameter primary mirror will
also be bigger, much bigger. The telescope will
have nearly seven times more light collecting
area than Hubble, allowing for unprecedented
infrared observations of distant objects from the
dawn of the universe some 14 billion years ago. Its
mirror and instruments will capture images of the
universe and break down the spectra of incoming
light to analyze the properties of galaxies, stars,
and the atmospheres of planets beyond our Solar
System.
“The recent completion of the critical design
review for Webb, and the delivery of all its
instruments to Goddard, mark significant progress
for this mission,” said NASA Administrator Charles
Bolden. “The design, build, delivery and testing of
these components took meticulous planning and
action here at Goddard and with teams across the
country, as well as with our international partners.
It’s very exciting to see it all coming together.”
A joint project between NASA, the European
Space Agency (ESA), and the Canadian Space
Agency (CSA), Webb will have been in planning,
design , and development for over 20 years
when it is launched atop an Ariane-5 rocket
from Arianespace’s ELA-3 launch complex at
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