Wednesday, April 28, 2010

Webb Telescope Passes Mission Design Review Milestone

NASA's Northrop Grumman-built James Webb Space Telescope has passed its most significant mission milestone to date, the Mission Critical Design Review, or MCDR. This signifies the integrated observatory will meet all science and engineering requirements for its mission.

"I'm delighted by this news and proud of the Webb program's great technical achievements," said Eric Smith, Webb telescope program scientist at NASA Headquarters in Washington.

"The independent team conducting the review confirmed the designs, hardware and test plans for Webb will deliver the fantastic capabilities always envisioned for NASA's next major space observatory. The scientific successor to Hubble is making great progress."

NASA's Goddard Space Flight Center, in Greenbelt, Md., manages the mission. Northrop Grumman, Redondo Beach, Calif., is leading the design and development effort.

"This program landmark is the capstone of seven years of intense, focused effort on the part of NASA, Northrop Grumman and our program team members," said David DiCarlo, sector vice president and general manager of Northrop Grumman Space Systems.

"We have always had high confidence that our observatory design would meet the goals of this pioneering science mission. This achievement testifies to that, as well as to our close working partnership with NASA."

The MCDR encompassed all previous design reviews including the Integrated Science Instrument Module review in March 2009; the Optical Telescope Element review completed in October 2009; and the Sunshield review completed in January 2010. The project schedule will undergo a review during the next few months.

The spacecraft design, which passed a preliminary review in 2009, will continue toward final approval next year.

The review also brought together multiple modeling and analysis tools. Because the observatory is too large for validation by actual testing, complex models of how it will behave during launch and in space environments are being integrated. The models are compared with prior test and review results from the observatory's components.

Although the MCDR approved the telescope design and gave the official go-ahead for manufacturing, hardware development on the mirror segments has been in progress for several years.

Eighteen primary mirror segments are in the process of cryo-polishing and testing at Ball Aerospace in Huntsville, Ala. Manufacturing on the backplane, the structure that supports the mirror segments, is well underway at Alliant Techsystems, or ATK, in Magna, Utah.

This month ITT Corp. in Rochester, N.Y., demonstrated robotic mirror installation equipment designed to position segments on the backplane. The segments' position will be fine-tuned to tolerances of a fraction of the width of a human hair. The telescope's sunshield moved into its fabrication and testing phase earlier this year.

The three major elements of Webb - the Integrated Science Instrument Module, Optical Telescope Element and the spacecraft itself - will proceed through hardware production, assembly and testing prior to delivery for observatory integration and testing scheduled to begin in 2012.

The Webb is the premier next-generation space observatory for exploring deep space phenomena from distant galaxies to nearby planets and stars.

The telescope will provide clues about the formation of the universe and the evolution of our own solar system, from the first light after the Big Bang to the formation of star systems capable of supporting life on planets like Earth. The telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency.

Wednesday, April 21, 2010

NASA Administrator Visits Marshall's X-Ray and Cryogenic Facility

NASA Administrator Charles Bolden, second from right, listens as Dave Chaney, right, a principle optical engineer for Ball Aerospace Technologies Corp. in Boulder, Colo., explains how the James Webb Space Telescope mirror segments are tested in the Marshall Space Flight Center's X-ray and Cryogenic Facility, or XRCF, in Building 4718. From front are Helen Cole, Webb telescope activities project manager at Marshall; Charles Scales, NASA associate deputy administrator; and Robert Lightfoot, Marshall center director.

The XRCF at the Marshall Center is the world's largest X-ray telescope test facility and a unique, cryogenic, clean room optical test facility. Cryogenic testing will take place in a 7,600 cubic foot helium cooled vacuum chamber, chilling the Webb flight mirror from room temperature down to frigid -414 degrees Fahrenheit. While the mirrors change temperature, test engineers will precisely measure their structural stability to ensure they will perform as designed once they are operating in the extreme temperatures of space.

NASA's James Webb Space Telescope is a large, infrared-optimized space telescope that will be the premier observatory of the next decade. It will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System. Its instruments will be designed to work primarily in the infrared range of the electromagnetic spectrum, with some capability in the visible range.

Northrop Grumman is the prime contractor for the Webb telescope, leading a design and development team under contract to the Goddard Center.

The James Webb Space Telescope is expected to launch in 2013. NASA's Goddard Space Flight Center in Greenbelt, Md. is managing the overall development effort for the Webb telescope. The telescope is a joint project of NASA and many U.S. partners, the European Space Agency and the Canadian Space Agency. (NASA/MSFC/David Higginbotham)

Saturday, April 10, 2010

Picture of the Day #6

Caption: Goddard technicians working with the ISIM Test Structure or ITS. ISIM will sit atop this during space environmental testing.

Credit: NASA, Chris Gunn

Tuesday, April 6, 2010

Viewpoint: The Two Pillars of NASA

We are at a pivotal period in defining NASA’s future. In the current debate about redirecting U.S. civil space activities, it is important to keep this in mind: Both human space exploration and space science are fundamental to that future. The partnership between human spaceflight and space science programs flourishes when their mutual interests are not just simply aligned, but when they find ways together to build on their respective strengths.

The most prominent recent example was the return of seven astronauts to the Hubble Space Telescope to install new scientific instruments and repair failed components, making it more powerful than at any time since its launch nearly two decades ago. This partnership is core to NASA’s mission and is an essential element to achieving the next great leaps in space science.

The proposed “flexible path,” in which NASA would not focus on returning astronauts to the Moon but send humans and robots to a variety of points far from Earth, provides the opportunities to reach the next exciting frontiers in space science. As scientists, we seek to see farther and with greater clarity in order to reveal nature’s unseen phenomena. This will require increasingly large and complex structures well beyond low Earth orbit. Some of these scientific facilities will require assembly in orbit and launch vehicles capable of delivering massive payloads to high Earth orbits, Sun-Earth Lagrange points, and beyond. NASA’s current plan recognizes and enables this by laying out a sequence of realistic and frequent steps to extend our ability to build, deploy and operate advanced spacecraft at ever-increasing distances from Earth.

As successful as NASA has been over its 50-plus years, NASA’s new plan can enable both revolutionary new scientific capabilities from space and, at the same time, propel our human exploration of space forward. Here are two prime examples:

A little over two decades ago, the first planet was found orbiting a distant star. Now, more than 400 such planets are known, and NASA’s Kepler mission will reveal how common are Earth-size planets located in the temperate zones around their host stars where liquid water can exist on a planet’s surface. The James Webb Space Telescope may be able to study the atmospheres of a handful of Earth-like planets, but only if a separate “star shade” spacecraft is flown alongside.

To definitively address the question of whether life exists elsewhere in the universe, however, requires a space telescope that is at least four times larger than the Hubble and at least four times more precise in its imaging capabilities than the Webb telescope. With such an observatory, we will be able to directly search for the faint signatures of life in the atmospheres of more than 100 planets around stars as far away as 60 light years, allowing us, for the first time in history, to systematically address the question: “Are we alone?” A still larger telescope would enable even more—the ability to detect oceans and track changes in weather and seasons on potentially habitable worlds.

One of the other major frontiers of astrophysics is to “see the beginning.” The quest to see back to the time when the very first stars formed will tell us much about how the universe came to be filled with all the chemical elements we see today and which enable life. But detecting these first stars is a terrific challenge. The Webb telescope will detect the first galaxies these massive stars formed, but will not be able to see the X-ray-emitting remnants of each of those first stars—the black holes they leave behind. We can fill that gap with a next-generation large X-ray telescope that is 1,000 times more sensitive than any X-ray observatory ever built.

Both of these remarkable next-generation telescopes are tantalizingly within reach but will require new heavy-lift launchers or assembly in space. They will also likely be designed to be serviceable (either by humans or robotic spacecraft) to allow them to pursue scientific investigations for decades beyond their commissioning. These capabilities are precisely the same ones our human space exploration program will require to make the next major foray into our Solar System. The two pillars of NASA—exploration and science—have made it synonymous with inspiration, vision and discovery. Both are intrinsically outward-looking endeavors. The next steps can be revolutionary, if we think boldly.

Marc Postman is an astronomer at the Space Telescope Science Institute in Baltimore and works on future mission concepts. Kathryn Flanagan is a senior scientist at the institute and heads its mission office for the James Webb Space Telescope.


Students Bring Fresh Perspective and New Technology to Webb Telescope

Engineers at Ball Aerospace test the Wavefront Sensing and Control testbed to ensure that the 18 primary mirror segments and one secondary mirror on JWST work as one. The test is performed on a 1/6 scale model of the JWST mirrors. Credit: NASA/Northrop Grumman/Ball Aerospace

Deep inside Building 5 at NASA's Goddard Space Flight Center in Greenbelt, Md., graduate students are on the front lines of technology development adjusting lasers and mirrors and spending long hours at a computer terminals. University partnerships are playing key roles in developing new and innovative technologies for NASA missions while creating a pathway for future NASA scientists and engineers.

"Investments in students today help us build what comes after the Webb telescope," said Lee Feinberg, Webb telescope Optical Telescope Element Manager at NASA Goddard. "University professors serve on our advisory boards. It allows us to tap the brightest minds in the country."

Past experience bears out Feinberg's observations.

Six years ago, Matthew Bolcar was a graduate student from the University of Rochester, N.Y. when he started working at NASA Goddard. He has been exploring interesting problems and developing risk-reduction techniques related to aligning segmented mirrors on the Webb telescope.

The Webb telescope primary mirror is composed of 18 segments that will unfold to create a single 6.5-meter (21-foot) mirror system once the observatory reaches orbit and begins operations. To work properly, the mirrors must be perfectly aligned. "If there were a problem, the telescope's operators could adjust the mirrors from the ground to correct for any possible misalignments," said Bruce Dean, group leader of the Wavefront Sensing and Control (WFSC) group at NASA Goddard.

Dean's group was charged with developing the software to compute the optimum position of each of the 18 mirrors, and then adjusting and aligning them, if necessary. The work was funded by the Webb telescope technology development program and was patented by Goddard in 2009. Goddard worked together with Ball Aerospace & Technologies Corp. in 2005, to develop this flight software for the Webb Space Telescope.

In 2006-2007, a team of engineers from both Goddard and Ball Aerospace & Technologies Corp., successfully tested the WFSC algorithms on a laboratory model of the Webb Telescope, proving they are ready to work in space.

Today, Bolcar is a full-time optical engineer for the Goddard WFSC group. Currently, he is working on the Thermal InfraRed Sensor (TIRS) instrument that will fly on the Landsat Data Continuity Mission (LDCM), the next in a series of satellites that have remotely sensed Earth’s continental surfaces for more than 30 years. He's also working on an experimental instrument, called the Visible Nulling Coronagraph (VNC) that would be used for exoplanet detection.

The graduate fellowship and co-op programs give NASA time to train students for optical engineering. "It takes four to five years to really train someone in wavefront-sensing technology," Dean added.

University partnerships are a great way to get young engineers and scientists interested in NASA, Bolcar agreed. "When you're a graduate student, wherever the funding is, you are going to develop partnerships and relationships," he added. "There is a potential to go beyond graduate school. It's good for the university and its good for attracting young talent to NASA."

Alex Maldonado, a University of Arizona graduate student in optical engineering, is following in Bolcar's footsteps. He spends half his time working at Goddard as a co-op student and the other half taking classes at the university in Tucson, Ariz. When at Goddard, he researches new techniques for polishing optical lenses to prevent light scattering.

Astronomers need bigger and smoother mirrors that will collect more light to allow scientists to see faint objects farther into the distant universe. A common and effective technique for shaping optical lenses is called diamond-turning, where a diamond tip cuts away the lens material. However, this technique also introduces flaws that can deflect light. Maldonado spends much of his time designing and executing testing procedures to see if new polishing techniques reduce this effect -- efforts that will be applied to the Near Infrared Camera (NIRCam), a Webb telescope imager.

The University of Arizona is providing the Near Infrared Camera (NIRCam) to the Webb Space Telescope, an imager with a large field of view and high angular resolution. Prof. Marcia Rieke at the University is the lead for that instrument.

The James Webb Space Telescope is the next-generation premier space observatory, exploring deep space phenomena from distant galaxies to nearby planets and stars. The Webb Telescope will give scientists clues about the formation of the universe and the evolution of our own solar system, from the first light after the Big Bang to the formation of star systems capable of supporting life on planets like Earth.

"In addition to the students, we work with the professors," according to Dean. Bolcar's graduate professor, James R. Fienup, is a world-renowned expert in optics. "We asked him to help us cover high-risk areas on the Webb telescope," said Dean.

"This is a win-win for the schools and NASA," said Feinberg. "We fund their graduate students, and in return, we get really bright, fresh minds working on NASA's most challenging missions.

Expected to launch in 2014, the telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency.

Wednesday, March 31, 2010

A View of the JWST NIRSpec Instrument

The Universe has always set the standard for colors. It produces all possible combinations of colors, granted not always in the visible light spectrum. But figuring out how these nuances intertwine is absolutely essential to, for example, determining the distance a certain object is from Earth, what chemicals it contains and so on. This is why the most impressive space observatory ever built, the James Webb Space Telescope (JWST), will feature an instrument perfectly capable of extracting this sort of data from whatever wavelengths of light enter its detectors.

The Near-Infrared Spectrograph (NIRSpec) device will be one of the most advanced spectrographs ever developed, and undoubtedly the most complex to ever fly to space. EADS/Astrium is the European Space Agency's (ESA) prime contractor for the overall NIRSpec instrument, but some of the components were constructed at the NASA Goddard Space Flight Center (GSFC), in Greenbelt, Maryland. The prototype for the actual NIRSpec instrument that will fly on the JWST recently arrived at the GSFC for preliminary testing, from its construction site in Germany.

“A spectrograph is an instrument that separates light into a spectrum. One example of a spectrograph that most folks know about is a chandelier (or diamond ring). When sunlight shines through it, it breaks it up into colors. NIRSpec analyzes those colors from deep space to help us solve mysteries,” explains GSFC expert Bernie Rauscher. He is the deputy project scientist of the telescope's Integrated Science Instrument Module (ISIM) and also the principal investigator of the NIRSpec Detector Subsystem.

This particular spectrograph will have the ability to analyze more than 100 cosmic objects at the same time, as its components were especially designed for this task. The instrument will collect readings in the infrared portion of the electromagnetic spectrum, which will enable researchers analyzing data from the instrument to determine the age, chemical composition and distances of faint galaxies. One of the primary mission goals for the James Webb Space Telescope will be to determine how galaxies began to form in the early Universe, and so this ability that the NIRSpec has will be absolutely fundamental to completing its mission.

Tuesday, March 30, 2010

Hubble's successor one step closer to completion

A working replica of MIRI - the pioneering camera and spectrometer for the James Webb Space Telescope - has just been shipped (16th March) from the Science and Technology Facilities Council’s Rutherford Appleton Laboratory to NASA’s Goddard Space Flight Centre, bringing the Webb Telescope one small step closer to embarking on its journey into space where it will produce the sharpest images yet of the farthest depths of the cosmos.

The Webb telescope, a joint collaboration between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA), is a large, cold orbiting infrared observatory that will succeed the currently operating Hubble Space Telescope. With the help of MIRI and its three other sophisticated instruments, it will be able to examine the first light in the universe and investigate the evolution of galaxies and the process of star and planet formation - helping to answer some of the fundamental questions about the origin of our Universe.

MIRI (Mid InfraRed Instrument) is an infrared camera and spectrometer that will operate as part of the Webb telescope to observe the Universe at wavelengths that are difficult or impossible to observe from the ground. It is an international project combining the talents of a consortium of European partners, the European Space Agency, and an international science team with those of scientists and engineers at NASA’s Jet Propulsion Laboratory.

The MIRI Structural Thermal Model realistically replicates the thermal, mechanical and optical alignment characteristics of the real flight model MIRI. It was assembled at the Science and Technology Facilities Council’s Rutherford Appleton Laboratory (RAL) from modules built by the University of Leicester, CEA in France, CSL in Belgium, JPL in the USA, Nova-Astron in the Netherlands, STFC’s UK ATC, & the Danish Space Research Centre, with system engineering, product assurance and management provided by Astrium Ltd. It has already been subjected to an extensive series of tests at RAL, and later this year it will be used at NASA’s Goddard Space Flight Centre for pre-integration testing with the Integrated Science Instrument Model (ISIM) - the key element of JWST that holds all four instruments in the correct positions. Meanwhile engineers across Europe and the USA are pressing ahead at full speed to build the flight instrument, which is due for delivery next year.

“The MIRI team is delighted to have reached this important technical milestone after many years of design and development work for the instrument” said the European PI, Gillian Wright of STFC’s UK Astronomy Technology Centre.

George Rieke, MIRI Science Team Lead at University of Arizona, Tucson added, "It is inspirational to see how well the team has worked to make this happen." "It is another big step toward making MIRI a reality."

When launched in 2014, the Webb telescope will have a set of four instruments, including MIRI. MIRI will provide enormous increases in sensitivity, spatial and spectral resolution for three key reasons: Firstly, its location in space will remove the blocking and large background noise effects of the atmosphere which limit ground-based telescopes. Secondly, the telescope is cooled to a very low temperature, reducing its emission and greatly improving its performance. Thirdly, the telescope’s mirror is larger then any other infrared space observatory, giving improved angular resolution and collecting area. This combination makes the Webb telescope a very powerful space observatory which promises to revolutionise our view of the cosmos yet again - just as Hubble did.

The UK is playing a key role in the Webb telescope with the Science and Technology Facilities Council (STFC) leading the European development of the MIRI Optical System. This UK contribution includes leadership by the European PI based at STFC’s UK ATC; Astrium Ltd providing the project management, PA, and system design/engineering; STFC’s Rutherford Appleton Laboratory (RAL) responsible for the Assembly, Verification and Test and the thermal systems work; STFC’s UK ATC designing and building the spectrometer pre-optics module; and the University of Leicester leading the structure and mechanical systems work for MIRI.

Dr David Parker, Director of Space Science and Exploration at the British National Space Centre (BNSC), said, “With the delivery of this sophisticated replica of MIRI, we’ve reached another important milestone in the build of this new window on the ancient Universe. Right now, the UK is involved in many exciting, new space projects. With the upcoming creation of a UK executive space agency we will ensure that the UK continues to play key roles in amazing discovery machines like James Webb Space Telescope.”

Professor Richard Holdaway, Director of Space Science and Technology at the Science and Technology Facilities Council’s Rutherford Appleton Laboratory, added, “The shipping of the MIRI replica to NASA’s Goddard Space Flight Centre, highlights again, the effectiveness of international collaboration on a mission of this size. Each organisation, including Rutherford Appleton Laboratory’s Space Science and Technology Department, contributes their own set of skills and expertise to the project, gradually steering us towards its completion”.

Matt Greenhouse, Project Scientist for the Webb telescope Science Instrument Payload at NASA's Goddard Space Flight Center, Greenbelt, Md. said, "Receipt of the MIRI structural thermal (STM) model represents a major milestone in 8 years of development work by the joint ESA and JPL instrument team. Tests with this prototype model of the MIRI, conducted at Rutherford Appleton Laboratories in the UK, have shown that this science instrument is on track to meet all of its performance requirements. Upon receipt of the STM, GSFC engineers will begin testing it with supporting systems in the Webb telescope Integrated Science Instrument Module to facilitate smooth integration of the flight model."