The Herschel spacecraft is now undergoing a series of mechanical tests
at ESA’s European Space Research and Technology Centre, ESTEC. The
tests are carried out to ensure that the spacecraft can withstand the
acoustic and vibration loads that it will encounter during launch.
The vibration tests were started on Friday, 20 June and will be
completed next week. In the video, taken on 23 June, the spacecraft
can be seen fastened on an electrodynamic shaker inside a clean room.
It is seen being shaken along its longitudinal axis (the X-axis) at
frequencies starting from 4 Hertz, increasing to 100 Hertz over a
period of about 80 seconds.
Such vibration tests will also be performed along the two lateral axes
(the Y and the Z axis), four times each, with differing loads each
time. The spacecraft’s electronic components are checked for normal
functionality before and after each run.
Earlier this month, on 5 and 6 June, Herschel successfully passed the
acoustic test. During the test, the spacecraft was subjected to
acoustic noise, generated to simulate the noise levels that it will
encounter during launch. The test was carried out at ESTEC’s Large
European Acoustic Facility (LEAF).
The Herschel infrared observatory’s telescope will carry the largest
mirror ever flown in space. With this telescope and its three science
instruments, it will observe and study relatively cool objects
everywhere in the Universe, in unprecedented detail. Herschel will
study the birth and evolution of a wide range of celestial bodies –
from stars in our own backyard to distant galaxies.