The yield to science will be immeasurable if it works. That is my greatest concern. The deployment of this telescope is extremely complex and if any part of that deployment fails, the entire $10B investment is lost.

http://www.nibletz.com/science/james-webb-space-telescope-advanced-space-telescope-date/


Page 18 and 19 of the GAO report -

http://www.gao.gov/assets/680/674309.pdf

Hopefully they will get it right the first time.

They failed to spot the mis-grind by that much.

http://www.courant.com/courant-250/moments-in-history/hc-hubble-telescope-20140410-htmlstory.html

It will be at the L2 Lagrange point.


Too far away for easy servicing. If it fails, the spacecraft will be abandoned.

info. from Hubble will help it to be right the first time.

But this link does: http://jwst.nasa.gov/orbit.html

The James Webb Space Telescope will not be in orbit around the Earth, like the Hubble Space Telescope is - it will actually orbit the Sun, 1.5 million kilometers (1 million miles) away from the Earth at what is called the second Lagrange point or L2. What is special about this orbit is that it lets the telescope to stay in line with the Earth as it moves around the Sun. This allows the satellite's large sunshield to protect the telescope from the light and heat of the Sun and Earth (and Moon).

the probability is low ... no idea.

Unless you're in low earth orbit, space junk is pretty well dispersed. Even the asteroid belt, which we think of as densely packed because of all the animated images we've seen, is pretty sparsely populated.