HIFI is one of three instruments at the heart of the Herschel Space Observatory. With a 3.5 metre diameter mirror, Herschel is the largest space telescope ever launched. Herschel's instruments are cooled to almost absolute zero and observes wavelengths that have never been seen before. Herschel was launched in May 2009 and is already providing scientists with never-before-seen imagery of the universe.
The key science objectives of the Herschel observatory are to study the formation of stars and galaxies, and to investigate the relationship between the two. Examples of Herschel's specific investigations are:
- A survey of the formation and evolution of elliptical galaxies and the central bulges in other galaxies during the first third of the Universe's history.
- Observations of star formation and young (and old) stars to reveal the physical and chemical processes in earlier (and the later) phases of a star's life.
- Observations of the atmospheres of the cool outer worlds in our Solar System and of comets.
- Understanding the physical processes and energy-generating mechanisms in galaxies.
- Detailed studies of the physical and chemical processes in the gas and dust not yet bound into stars and planets. These investigations will be conducted in our Galaxy and others. They will help to investigate why and how stars form from interstellar clouds, and planets from circumstellar discs. It will also provide fundamental clues about complex organic molecules found, for instance, in the atmospheres of comets.
Herschel's Heterodyne Instrument for the Far Infrared (HIFI) is the most complex space instrument ever built in the Netherlands. With its highly accurate spectrometry, HIFI is used to obtain information about the chemical composition, kinematics, and physical environment of infrared sources. HIFI addresses many key questions in modern astrophysics with a unique combination of highly accurate spectral resolution and ability to make thousands of sub-millimeter wavelength observations.
HIFI provides new insight into the origin and evolution of the molecular universe, star forming regions with proto-planetary disks around new stars, the out-gassing of comets, vertical water distribution in the Giants of our solar system and on Mars, and even distant, possibly primordial, galaxies.
HIFI was designed and built by a consortium (led by SRON) of scientists and institutes from The Netherlands, France, Germany, USA, Canada, Ireland, Italy, Poland, Russia, Spain, Sweden, Switzerland and Taiwan. TNO contributed a highly advanced optical design including more than 100 mirrors and used diamond-turning facilities to manufacture all of the off-axis parabolic mirrors for the project. TNO, in cooperation with Mecon Engineering, was also responsible for mechanical design, resulting in an ultra high stiffness to mass ratio. Furthermore, advanced optical and mechanical alignment helped TNO work hand in hand with SRON to see that the varying and complex inputs to HIFI successfully came together and met the rigorous requirements to form the Netherlands' largest space instrument ever.