One of our planet’s best eyes into the universe has closed. The Herschel Space Observatory — just Herschel to its friends — was the largest infrared telescope we had in orbit, with an ability to see into the coldest regions of space. (By “we” I mean “we humans,” because Herschel was built and operated by the European Space Agency.) Those are the areas where giant dust clouds obscured the light that other telescopes could see, but Herschel peered right through them to photograph the star-forming nurseries they concealed.
It was launched in 2009 with enough liquid helium to cool its instruments for three years. Unlike every electronic appliance I’ve bought in the last decade, Herschel outlived its predicted lifespan, by an impressive 25 percent. But its helium has boiled away and its instruments have gone dark. The last act it will perform is to shift its orbit from the Earth to the sun, where it will probably remain until space travel is boringly normal and somebody grabs it for salvage.
Both the Atlantic and Wired put up photo galleries sampling the wonders that Herschel revealed, and both are worth a look. I particularly enjoyed the Atlantic’s collage of the Andromeda Galaxy as seen by two different telescopes (Herschel in infrared and XMM-Newton in x-ray) plus an astrophotographer’s “normal” camera. The combination of different views is a great illustration of just how limited our biological eyes are in seeing what’s really out there.
According to the ESA, Herschel has made more than 35,000 individual observations across 600 programmes. That dataset is so vast that scientists are still combing through it
…and will be for a long time to come.