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.