Table of Contents

News from Herschel

• December 1, 2009 – The Herschel Space Observatory Hones in on our
  Galactic Neighbours and Spies on a Comet
• July 10, 2009 – Updates for the Herschel and Planck missions

December 1, 2009

The Herschel Space Observatory Hones in on our Galactic Neighbours and Spies on a Comet

Unprecedented images bring familiar objects into focus

A series of images from the Herschel Space Observatory is providing scientists with new perspectives of some well known astronomical targets. Herschel has beamed back exceptionally good astronomical fingerprints (spectra) of a broad range of objects (from comets, to massive stars, star-forming regions and a variety of galaxies), including new evidence for water and the building blocks of life in the Universe.

Messier 82-A Starburst Galaxy in the Big Dipper (Ursa major)

This mosaic shows some of the early data and images acquired by Herschel's SPIRE instrument during its testing phase.

SPIRE captured these images of Messier objects 81 (M81) and 82 (M82), a pair of galaxies located in Ursa major (which contains the familiar asterism, the Big Dipper). As the spectrum suggests, SPIRE detected a strong presence of carbon monoxide in M82 (left), as well as atomic carbon and ionized nitrogen.

M82 is the nearest starburst galaxy to Earth (a mere 12 million light years away). The intense star formation in M82 has been triggered by the gravitational tidal forces caused by its close passage by its more massive neighbour, M81.

SPIRE is one of the two Herschel instruments in which Canadian scientists play a role. Astronomer Christine Wilson from McMaster University is the principal researcher on the Herschel project "Physical Processes in the Interstellar Medium of Very Nearby Galaxies" that produced this image. Led by Wilson, this group of scientists is examining the closest examples of every type of galaxy they can find to study the properties of the gases in galaxies and determine how gases relate to star formation.

Galactic Star Formation in the Orion Nebula (Orion Bar-DR21)

The Orion nebula (as seen here by the Hubble Space Telescope) is a familiar target for amateur astronomers. (Credit: NASA, ESA, M. Robberto (STScI/ESA) and The Hubble Space Telescope Orion Treasury Project Team)

Compare Hubble's view of the Orion nebula (left) with the above image by NASA's Spitzer Telescope. The different wavelengths used to image the same object reveal new information—new stars are revealed in the Spitzer infrared image, which peers through the colourful shells of gas that give the nebula its orchid-like appearance. Likewise, the spectrum produced by Herschel (above graph) gives astronomers new pieces of the puzzle by detecting the chemical elements that make up the object.

This SPIRE spectrum reveals exciting new clues about a star-forming region of the famous Orion nebula known as the Orion Bar. SPIRE made the first-ever detection at long wavelengths of an ion known as methylidynium, a key constituent for larger carbon-bearing molecules, such as organic molecules-the building blocks of life. By measuring the heights of the spikes on the left side of the chart, astronomers are able to estimate the temperature and density of interstellar gas in this region.

Water on Comet Garradd

The peak in the above spectrum, produced by Herschel's HIFI (Heterodyne Instrument for the Far Infrared) instrument, confirms the presence of water on Comet Garradd. Some of the studies done with HIFI will compare the characteristics of water and volatile organic molecules released by different comets in the Solar System as they approach the Sun.

Comets are essentially amalgamations of small dust grains held together by ice—like dirty snowballs. They were formed some 4.5 billion years ago in cold, outer regions of the Solar system. For most of their history, comets dwell far from the Sun, and therefore represent a pristine record of the early conditions when the Solar System and the planets were formed. Scientists believe that comets may have contributed greatly to water on the Earth and other terrestrial planets. Small perturbations in their orbit can propel comets inwards. When they approach the Sun, the increased heat sublimates the ice releasing water and other molecules into the vapour phase; this means that the composition and characteristics of the comet can be easily measured.

The Herschel Space Observatory was launched on May 14, 2009 on board the same Ariane 5 rocket that was carrying the Planck Space Telescope. With funding from the Canadian Space Agency, several Canadian institutions and entrepreneurs contributed to Herschel by taking part in the development of two of the three science instruments: the Heterodyne Instrument for the Far Infrared (HIFI) and the Spectral and Photometric Imaging Receiver (SPIRE).

Professor Michel Fich of the University of Waterloo is the Principal Investigator for HIFI in Canada. COM DEV, Cambridge, Ontario, is the prime contractor for Canada's contribution to HIFI.

Professor David Naylor of the University of Lethbridge is the Principal Investigator for Canada's contribution to SPIRE through ISIS, the Institute for Space Imaging Science (which also includes the University of Calgary and Athabaska University). Blue Sky Spectroscopy, Lethbridge, Alberta, hosts the centre of expertise for the SPIRE imaging spectrometer and is responsible for processing the spectral data shown in the figures.

The Canadian Herschel team includes scientists from the universities of British Columbia, Calgary, Western Ontario, Toronto, Victoria, McMaster University and the National Research Council Canada.

July 10, 2009

Updates for the Herschel and Planck missions

The European Space Agency announced that the Herschel Space Observatory has begun producing data and is performing far beyond expectations. Herschel was launched simultaneously with the Planck Space Telescope on May 14, 2009.

Herschel and Planck cruising to L2. (Artistic impression: ESA - AOES Medialab)

View of the galaxy M51 as seen by PACS during testing.
(Photo: ESA and the PACS Consortium)

To date, Herschel's three instruments (the Heterodyne Instrument for the Far Infrared (HIFI), the Spectral and Photometric Imaging Receiver (SPIRE) and the Photometric Array Camera and Spectrometer (PACS)) were tested on a few astronomical targets before their initial calibration had even begun. Their first results have already surpassed data gathered by previous missions. Herschel's goal is to probe the Universe at far infrared and sub-millimetre wavelengths to determine how stars, planets and galaxies form and evolve.

Planck's instruments (the Low Frequency Instrument (LFI) and the High Frequency Instrument (HFI)) are being calibrated and optimized. They are nearly ready to observe the sky full-time. Planck's planned mission is to complete two surveys of the entire sky to map the microwave background radiation - the remnants from the Big Bang.

Herschel and Planck's ultra-precise science instruments were developed by an international consortium, including several Canadian teams.

Professor Michel Fich of the University of Waterloo is the Principal Investigator for Herschel-HIFI in Canada. COM DEV, Cambridge, Ontario, is the prime contractor for Canada's contribution to HIFI.

Herschel and Planck separate after the launch. (Animation: ESA)

Professor David Naylor of the University of Lethbridge is the Principal Investigator for Canada's contribution to Herschel-SPIRE. Blue Sky Spectroscopy, Lethbridge, Alberta, hosts a centre of expertise for the SPIRE Imaging Fourier Transform Spectrometer. The Canadian Herschel team includes scientists from the universities of British Columbia, Calgary, Western Ontario, Toronto, Victoria, McMaster University and the National Research Council Canada.

Professor Douglas Scott of the University of British Columbia is leading the Canadian Planck-LFI team. The Planck-HFI team is led by Professor J. Richard Bond of the University of Toronto.

The Canadian teams have spent more than a decade working with their international colleagues to plan for the Herschel and Planck missions, and will be directly involved in using the data to answer some of the most fundamental astronomical questions about the Universe.

For more information about Canada's role in the Herschel and Planck missions visit the: www.asc-csa.gc.ca/eng/satellites/herschel/default.asp and www.asc-csa.gc.ca/eng/satellites/planck.asp

For details about Herschel's first discoveries, visit: www.esa.int/esaCP/SEMAYT6CTWF_index_0.html