2001 October 02
After seven years of design and construction but only two weeks of commissioning, a remarkable first light image was obtained with a new state-of the-art instrument at the Gemini North Telescope on Hawaii's Mauna Kea. The image of the large galaxy in Pisces called NGC 628 (or Messier 74) has been called the "Perfect Spiral Galaxy" due to its nearly ideal form, which is clearly revealed in this new image.Named GMOS or the Gemini Multi-Object Spectrograph, the instrument that took the image is primarily designed for spectroscopic studies where several hundred simultaneous spectra are required, such as when observing star and galaxy clusters. However, as the dramatic new image demonstrates, GMOS also has the ability to focus beautiful astronomical images on its huge array of over 28 million ultra-sensitive pixels. When combined with Gemini's 8.1-meter main mirror, the GMOS first-light image of this spiral galaxy leaves no doubt about the instrument's potential on Gemini.The instrument's first light image of the galaxy that is number 74 in Charles Messier's catalogue of celestial show-pieces (a.k.a. M-74), clearly shows many features of the galaxy such as star clusters, gas clouds and dust lanes. Some of these objects are similar to what we can see in our own Milky Way with the naked eye or a small telescope on a clear moonless night. "To be able to routinely see fine details like this in a galaxy more than 30 million light years away is quite remarkable and helps to give some perspective of what our own galaxy might look like if there were another Gemini sized telescope looking back at us!" says Gemini North's Associate Director Dr. Jean-Rene Roy. It is estimated that M-74 is home to about 100 billion stars making it slightly smaller than our Milky Way."This instrument took world-class data on its first night on the sky performing perfectly, right out of the box, or at least the 24 crates that brought the 2-ton instrument to Hawaii from Canada and the UK," said Gemini Observatory Director Dr. Matt Mountain. "This is a considerable testament to the professionalism, planning and teamwork of the multi-national group of astronomers and engineers from the Herzberg Institute of Astrophysics in Canada, the UK's Astronomy Technology Center and Durham University (UK) who were able to build this instrument and commission it with our staff so successfully here on Mauna Kea. This type of multi-disciplined, multi-national effort represents a new and powerful way to do world-class observational astrophysics," continued Dr. Mountain. The instrument was built as a joint partnership between Gemini, Canada and the UK at a cost of about $5 million. Separately, the U.S. National Optical Astronomy Observatory provided the detector subsystem and related software.
Rick Murowinski from Canada's National Research Council's (NRC) Herzberg Institute of Astrophysics (HIA) served as Canada's Project Manager and Systems Engineer for this ambitious project from its inception in 1994. Murowinski said, "It's been a long project with selfless effort by many people, but to be able to see this instrument finally come together at the telescope, to see it work properly and immediately, is really wonderful! The Canadian and British team who conceived, designed and built this instrument is justifiably very proud of what we've accomplished together!"
It is anticipated that GMOS will begin full scientific operations later this year when astronomers from the 7-country Gemini partnership begin using the instrument for a wide variety of scientific studies. "It is extremely exciting to see the wide range of cutting-edge observations already scheduled for GMOS over the next few months," said Gemini Astronomer Dr. Inger Jorgensen, who led the instrument's commissioning effort. Dr. Jorgensen also said, "I'm most interested in the planned observations of distant galaxy clusters where Gemini is able to work like a time machine and look back in time to study a much younger universe than we see around us today."
The UK's Dr. Isobel Hook, who helped obtain the instrument's first multi-object spectroscopic data, said, "The first spectra produced by GMOS were brilliant! When you combine GMOS with Gemini's resolution and great light gathering power we are able to study details that would otherwise be lost. One area where I think this instrument will excel is in the study of supernova, or exploding stars in very distant galaxies. Once we can obtain spectra from these stars we will be able to better understanding the apparent acceleration of the universe."
Dr. Bob Abraham from the University of Toronto in Canada is eagerly looking forward to using GMOS on the Gemini North telescope. Abraham said, "To properly study distant galaxies, an instrument like GMOS needs to be mounted on a efficient large telescope that delivers exquisite image quality. Gemini is the first large telescope designed from the ground up to deliver on these requirements. GMOS is a dream instrument on a dream telescope."
Professor Roger Davies from Durham University in the north-east of England is the leader of the UK's GMOS team. He obtained some early scientific demonstration data that will soon be released to astronomers. For this observation, the light from individual galaxies in a distant, massive swarm of galaxies was collected.
According to Davies, "We were able to observe these galaxies as easily as if they were our close neighbors. Now we'll use this superb spectroscopic data to determine their mass, size and composition and look back in time to see how they have changed through cosmic history. The combination of Gemini's tremendous light collecting power and the technology of GMOS allowed us to obtain phenomenal data only a few days after the instrument was installed on the telescope. I can see that this instrument is going to keep astronomers very busy and extremely happy for a long time!"The Gemini Observatory is an international collaboration that has built two identical 8-meter telescopes. The telescopes are located at Mauna Kea, Hawaii (Gemini North) and Cerro Pachón in central Chile (Gemini South), and hence provide full coverage of both hemispheres of the sky. Both telescopes incorporate new technologies that allow large, relatively thin mirrors under active control to collect and focus both optical and infrared radiation from space. Gemini North has begun science operations and Gemini South is scheduled to begin scientific operations in late 2001.
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