James Webb's Keen Eyes Will Be Tested

One of the instruments operating in the infrared light domain will be tested just before Christmas, at the Rutherford Appleton Laboratory in Oxfordshire. The Mid-InfraRed Instrument equipping the James Webb Space telescope will have the role of observing the universe in the infrared spectrum, because the objects scientists are interested in are so cold that they are no able to radiate shorter wavelengths than light in the visible spectrum and emit high amounts of infrared radiation.

It will be used to study some of the unknown properties of the early universe and of the materials that form around newly born stars, with incredible accuracy and it's possible that it be able to take the first direct picture of the massive exoplanets.

Though it was developed in a collaboration between NASA and the European Space Agency, the responsibility for building MIRI's detectors, the cryocooler and the flight software of the telescope, fell on the shoulders of NASA's Jet Propulsion Laboratory in Pasadena.

So far, it has undergone tests at NASA's Goddard Space Flight Center, such as the alignment checks with a piece of the test equipment simulating the Integrated Science Instrument Module, which is part of the telescope where the MIRI instrument will be attached. MIRI will be the first instrument to be tested in the cryogenic performance phase.

According to Dr. Tanya Lim who is leading the MIRI testing team, multiple instruments and test equipment components will be brought from all over the world to ensure that they all work together. The same is available for the instrument's flight software that will be tested with the spacecraft and the ground software systems plus simulations of the telemetry readings and generating images of the test environment.

Due to the importance of the instrument the team is currently struggling to complete the tests before Christmas. MIRI is the biggest single flight instrument ever built at RAL and has presented special particularities related to the thermal control, since it will operate at lower temperatures than the rest of the spacecraft. The tests that took place in the first week have been specially designed to cool the instrument at temperatures as low as 6.2 Kelvin, in order to evaluate its performance.

In the beginning of next year, MIRI will participate in a series of tests at the MIRI Telescope Simulator, a special built facility in Spain that will be able to simulate the stars that it will probably see.

The James Webb Space Telescope is part of a program to build new space telescopes that will be able to look as far as 13 billion years into the past to understand the galaxy formation, stars and the evolution of solar systems and will begin observation somewhere in the year 2013.