This was all planned, but somehow it is still sad: European Space Agency’s Herschel space telescope is officially dead, its observing has been brought to a permanent end. HSO has exhausted all of its cryogen, there is no more superfluid liquid helium in the cryostat. This ends the more than three years of pioneering observations of the cool Universe, ESA reports.
The Herschel telescope allowed astronomers to look deep into space by detecting light emitted in the far-infrared and sub-millimetre regions of the spectrum. Earth’s atmosphere prevents most of this light from reaching ground-based telescopes, but Herschel could see the coldest and dustiest objects in space: cool star formations, massive black holes and dusty galaxies with newborn stars.