Herschel and Aquila

Even on a cloudless night, we have to look through our atmosphere to observe the Universe. Turbulence in the air causes stars to twinkle. This makes it impossible to study very fine details. Moreover, many types of electromagnetic radiation from space are blocked by the atmosphere: gamma rays, X-rays, ultraviolet radiation and large portions of the infrared and submillimeter spectrum cannot be observed from the ground. Therefore, ever since the dawn of the Space Age, telescopes have been put on board rockets and satellites.

The European Space Agency's Herschel Space Observatory (formerly called Far Infrared and Sub-millimetre Telescope or FIRST) has the largest single mirror ever built for a space telescope. At 3.5 metres in diameter the mirror will collect long-wavelength radiation from some of the coldest and most distant objects in the Universe. In addition, Herschel is the only space observatory to cover a spectral range from the far infrared to sub-millimetre.