Herschel Peeks at the Ingredients of Galaxies
The European Space Agency has released spectacular new observations from the Herschel Space Observatory, including the UK-led SPIRE instrument. Spectrometers on board all three Hershel instruments have been used to analyze the light from objects inside our galaxy and from other galaxies, producing some of the best measurements yet of atoms and molecules involved in the birth and death of stars.
The SPIRE Fourier Transform Spectrometer (FTS), which covers the whole submillimeter wavelength range between 194 and 672 microns, will be invaluable to astronomers in determining the composition, temperature, density and mass of interstellar material in nearby galaxies and in star-forming clouds in our own galaxy.
Professor Keith Mason, Chief Executive of the Science and Technology Facilities Council (STFC), which provides the UK funding for Herschel, said “Herschel has once again returned some spectacular indications of what is to come. This wealth of new data exists because of the dedication and skill of the scientists working on this project and will vastly expand our knowledge of the life cycle of stars.”
Professor Matt Griffin of Cardiff University, who is the SPIRE Principal investigator, said: “Some trial observations have been made during initial testing of the spectrometer, and it is clear that the data are of excellent quality, and even these initial results are very exciting scientifically, especially our ability to trace the presence of water throughout the Universe. The spectrometer was technically very challenging to build, and the whole team is delighted that it works so well.”
Professor Glenn White, of the Open University and STFC’s Rutherford Appleton Laboratory, and an expert in the field of molecular astronomy for which the SPIRE spectrometer is designed, said: “The exquisite sensitivity and quality of these early data reveal spectacular spectroscopic signatures that show the diversity and complexity of the birth processes common to the formation of star and planets. Herschel is going to help us trace the evolution and life of stars, to map the chemistry in our galactic neighborhood, and allow us to detect water and complex molecules in distant galaxies.”
Professor Mike Barlow of University College London, who will use the SPIRE instrument to study the material ejected into space by stars near the end of their lives, said: “The unprecedented spectral range and the wealth of detail revealed by the SPIRE spectrometer, in a hitherto almost unexplored region of the spectrum, promises to revolutionize our understanding of the formation of molecules and dust particles during the final stages of the lives of stars. These dust particles go on to play a crucial role in the formation of new stars
and provide the raw material for the planetesimals and planets that
form around them.”
Further details of the new observations by SPIRE, and by the other two Herschel instruments, may be found at the ESA Herschel Science Centre web site: http://herschel.esac.esa.int/
UK Herschel site: www.herschel.cf.ac.uk
The SPIRE Fourier Transform Spectrometer covers the submillimeter wavelength range (194-672 microns), and provides a complete survey of the source spectrum over that whole wavelength range in a single observation, something that has never been possible with previous submillimeter instruments.
At the same time as measuring the intensities of narrow spectral features from gas atoms and molecules, the SPIRE spectrometer also accurately measures the broadband emission from dust. With its multi-pixel detector arrays, it can also produce spectral images, allowing astronomers to measure the spatial variation in the interstellar material.
Herschel and SPIRE
The European Space Agency’s Herschel satellite carries the largest telescope to be flown in space and is designed to study the Universe at far infrared wavelengths. It will reveal the early stages of star birth and galaxy formation; it will examine the composition and chemistry of comets and planetary atmospheres in the Solar System; and it will examine the star-dust ejected by dying stars into interstellar space which form the raw material for planets like the Earth.
The SPIRE instrument has been built by a consortium of 18 institutes in eight countries (UK, France, Italy, Spain, Sweden, USA, Canada and China), led by Prof. Matt Griffin of Cardiff University. The instrument was assembled at the STFC’s Rutherford Appleton Laboratory in the UK.
Images of Herschel are available from the STFC Press Office
Herschel Mission Timeline
* Herschel was launched on an Ariane 5 from Europe’s Spaceport in Kourou, French Guiana, on 14 May 2009.
* Commissioning Phase: In the first few days after launch basic spacecraft checks were done. About a week after launch, the Herschel scientific instruments were switched on for the first time and detailed commissioning of the instruments began.
* Performance Verification Phase: This began 60 days after launch, and is now nearing completion It has involved tests to ensure that the instrument operational modes and scientific data processing software are thoroughly checked and optimized.
* Science Demonstration Phase: Comprehensive trial scientific observations have already begun, involving execution of a selection of different kinds of observations and processing the data to produce scientific results. These will be presented at the Herschel Science Demonstration Workshop, in Madrid, on December 17 and 18.
* Routine Operations Phase: Routine operations will begin before the end of 2009, and will last for at least three years. The observational programs for the first 18 months have already been selected.
Contacts:
Julia Short
Press Officer, STFC
+44 (0)1793 442 012
julia.short@stfc.ac.uk
Mr. Chris North
UK Herschel Outreach Officer
Cardiff University
+44 (0)29 208 70537 or 76403
chris.north@astro.cf.ac.uk
Prof. Matt Griffin
Herschel-SPIRE Principal Investigator
Cardiff University
+44 (0)29 2087 4203
matt.griffin@astro.cf.ac.uk
Prof. Glenn White
The Open University, Milton Keynes
+44 (0)1908 652 735
g.j.white@open.ac.uk
Prof. Mike Barlow
University College London
+44 (0)20 7679 7160
mjb@star.ucl.ac.uk
