The new multi-wavelength satellite, XMM-NEWTON, an international research project involving France Anne Cordova, astrophysicist and vice chancellor for research at the University of California, Santa Barbara, is now scientifically operational and sending home images of celestial objects, which are available on the Internet.
With this new satellite, as with the Hubble telescope and the new Chandra space telescope, scientists begin a new era of space exploration. "We will be taking the deepest pictures yet of the X-ray sky, hoping to make new discoveries," said Cordova. "We will be observing bright binary stars in nearby galaxies, and pulsars and cataclysmic variables in our own galaxy."
One of the principal activities of XMM-Newton, (short for X-ray Multi-Mirror Mission -- Sir Isaac Newton) will be to study black holes ten times as massive as the sun, which can be in binary star systems drawing matter from a nearby star, said Cordova.
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Much larger black holes with a million to a billion sun masses are thought to be at the center of many galaxies, voraciously gobbling stars as they are attracted by gravity to the center. The XMM-Newton will be used by astronomers worldwide over a period of ten years to study these and various exotic stars and galaxies, and may include the first galaxies made when the universe was young.
All three major experiments designed for the satellite are working as planned, according to the official announcement today in Villafranca, Spain, made jointly by the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA). The name Newton was recently added to the spacecraft, after the famed British scientist Sir Isaac Newton who lived from 1642 to 1727.
Cordova, who served as NASA's chief scientist from 1993 to 1996, originally proposed the idea for a multi-wavelength capability to NASA in 1983 when she was staff scientist at the Los Alamos National Lab, but it wasn't accepted for lack of money.
Then she suggested the project to ESA in 1989 and it was chosen. So, the multi-wavelength satellite is the product of ESA, a 15-country consortium that is Europe's equivalent of NASA. NASA's involvement in the mission includes the contribution of critical components for two of the spacecraft's three science instruments and participation in the science-observing program. Through the Guest Observer Program, U.S. scientists will receive about one fifth of the observing time on the spacecraft during its first two years in orbit.
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Cordova and her team contributed to the construction of one of the European instruments, providing the data processing unit, the digital electronics modules, software and science support for the Optical Monitor instrument, a conventional but very sensitive optical telescope.
The XMM-Newton is large by satellite standards, said Cordova; it stands over 10 meters tall and has a "wing span," with solar panels extended, of 15 meters.
Cordova attended the launch in French Guyana with her family last December and called it "absolutely flawless, just beautiful." Her team's experiment, the Optical/Ultraviolet Monitor telescope, extends the range of the X-ray telescopes on the satellite to longer wavelengths, making it possible to observe cosmic sources over a much longer baseline of wavelengths. Until now it was not possible to compare so many different wavelengths, taken at the same point in time.
XMM-Newton is the first observatory to include X-ray, optical and UV telescopes, spanning a much greater wavelength range than Hubble and some other, smaller satellites that have some degree of multiwavelength capability. XMM-Newton's unique capability is high-throughput spectroscopy, said Cordova. The fact that it also has the multi-wavelength capability enhances its capability to do discovery science.
"Many sources of high-energy radiation have complicated spectral signatures," said Cordova. "Our vision, formulated in 1983, was to have the world's first 'multi-wavelength' satellite. Now it will be possible to understand much more about how these objects behave."
Regarding the name change, from XMM to XMM-Newton, to honor Sir Isaac Newton, Cordova said, "The name change comes as welcome news to scientists. It is fitting that this satellite is named after Sir Isaac Newton since he identified gravity as the force that accounts for the motions of the planets in orbits around the sun. The XMM-Newton satellite will be used to map the cosmos to much greater distances, where gravity determines the shapes of galaxies and clusters of galaxies and the structure of the universe itself."
Newton's work in mathematics, optics and physics laid the foundations for modern science. He made a major impact on theoretical and practical astronomy and today one cannot evoke an apple, a reflecting telescope, a light-splitting prism or a sextant without recalling Newton's contribution to science. "We have chosen this name because Sir Isaac Netwon was the man who invented spectroscopy and XMM-Newton is a spectroscopy mission," said Roger Bonnet, director of science for ESA.
Bonnett described the mission, "I am amazed by the quality of the pictures, as compared to previous X-ray missions. We see on them a lot of new sources, especially in the parts of the spectrum which correspond to the hottest temperatures. We see that the universe is hotter than we thought and that many new sources are appearing. We are very hopeful that many more objects will be discovered and that by extending the temperature measurements of the universe to many objects, we will have a much better picture of the history and the hectic behavior of stars at the end of their life."
"The spacecraft is behaving well," said Robert Laine, project manager for the satellite, which has been managed by ESTEC in the Netherlands. He added, "All instruments on board are working properly and today we are releasing the first images." Antonio Rodota, director general of ESA, congratulated the industry teams and the scientists involved on "the outstanding work and efforts in developing XMM, ESA's biggest and most innovative scientific spacecraft so far."
Others on Cordova's team at UC Santa Barbara are Timothy Sasseen, project manager; Robert Shirey and Jamie Kennea, postdoctoral researchers; Dirk Pandel and Jennifer West, graduate students; and Joshua MacAdam, undergraduate student. At Los Alamos, Cheng Ho and Bill Priedhorsky have worked on the experiment for the past decade, as have James Klarkowski and his group of engineers at Sandia National Laboratory. Most of the team has taken turns spending time since launch commissioning their experiment in Spain. Cordova said she expects that now that the satellite "is ready for science" additional students will join the project. All of the experimenters have guaranteed observation time to look at the objects in which they are most interested, said Cordova.
A variety of opportunities for European school children to get involved in activities relating to the XMM-Newton have been arranged. For example a there is a school competition to win satellite time for observation in conjunction with scientists working on the mission. For more information see the website sci.esa.int/xmm/competition.
For background on XMM-Newton visit the ESA science web pages at sci.esa.int/xmm or call the ESA Communication Department at 33-0-1-53-69-7155.
Images available on the ESA website at www.esa.int then Image Gallery, the News, and on the ESA Science homepage at: sci.esa.int/xmm/firstimages
For a biography of France Anne Cordova, astrophysicist and vice chancellor for research at UC Santa Barbara, visit research.ucsb.edu/connect/connect.htm
For information on the XMM-Newton Guest Observer Facility which will provide support to U.S. guest scientists in the form of data archives, technical guidance and software support see: heasarc.gsfc.nasa.gov/docs/xmm/smmgof.html
Background on the image which is available by request via e-mail: Credit: ESA
Among the first images received from the XMM-Newton is this X-ray image of the Hickson galaxy group (HCG-16) taken with the XMM-Newton X- ray telescopes compared to the optical image of the galaxies taken simultaneously with XMM-Newton's Optical Monitor telescope. The ability to record images simultaneously over a range of wavelengths is an important first for XMM-Newton, allowing new X-ray discoveries to be placed immediately in the context of more familiar images from the optical portion of the spectrum.
The HCG-16 viewed by the EPIC camera and by the Optical Monitor in the visible and ultraviolet wavelengths is one of approximately a hundred compact galaxy clusters listed by Canadian astronomer Paul Hickson in the 1980s. The criteria for the Hickson cluster groups included their compactness, their isolation from other galaxies and a limited magnitude range between their members. Most Hicksons are very faint, but a few can be observed with modest aperture telescopes.
Galaxies in Hickson groups have a high probability of interacting. Their study has shed light on the question of galactic evolution and effects of interaction. Investigation into their gravitational behavior has also significantly contributed to our understanding of "dark matter," the mysterious matter that most astronomers feel comprises well over 90 percent of our universe.
Observation of celestial objects from space over a range of X-ray, ultraviolet, and visible wavelengths, is a unique feature of the XMM-Newton mission. One EPIC -- PN view of the Hickson 16 group shows a handful of bright X-ray sources and in the background more than a hundred faint X-ray sources that XMM-Newton is revealing for the first time.
The ability to juxtapose the X-ray view of HCG-16 with that of the Optical Monitor is one of the great strengths of XMM-Newton in being able to routinely compare the optical, ultraviolet and X-ray properties of objects.
Many of the X-ray sources are revealed as elongated "fuzzy blobs coincident with some of the optical galaxies. Routine access to ultraviolet images is a first for the mission, allowing astronomers to learn much more about individual objects. Obtaining a ratio of the brightness of individual sources seen with different filters (filter spectroscopy) gives indications about their temperature and composition. Using XMM-Newton to search for variability from sources such as these will enable astronomers to hunt for the black holes thought to lurk at the centers of many galaxies.
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