Tagged: NASA Webb Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 2:35 pm on October 5, 2016 Permalink | Reply
    Tags: , , NASA Webb, Near infrared astronomy,   

    From Webb via The Washngton Post: “NASA puts finishing touches on telescope to look to back at first stars” 

    NASA Webb Header

    NASA Webb Telescope

    James Webb Space Telescope

    1

    Washington Post

    October 4, 2016
    Harrison Smith

    A million miles from Earth, observatory will see light from stars formed 13 billion years ago.

    2
    At the Goddard Space Flight Center in Greenbelt, Md., engineers examine the telescope’s gold-coated primary mirror. (Chris Gunn/NASA)

    In a cavernous, dust-free workroom at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, engineers and technicians are putting the finishing touches on one of the most ambitious telescopes ever built.

    When it’s launched in 2018, the James Webb Space Telescope will enable scientists to peer into the oldest, farthest reaches of the universe and search for signs of life on distant planets.

    “We want to see the first stars and understand how stars, galaxies and planetary systems are formed,” John Durning, deputy project manager for the Webb, said at Goddard recently while technicians worked inside the center’s 10-story “clean room.”

    “We don’t understand how we got here,” he added, “and we need to go to the beginning to figure that out.”

    Scientists theorize that the universe began with what is known as the big bang about 13.8 billion years ago and that the first stars formed 400 million years later. To see those stars, the Webb will use special instruments to study an invisible form of light that is given off by all objects, especially hot ones.

    Looking at that infrared light will allow the unmanned telescope to pull back the curtains of the universe and see stars too distant even for the Hubble, the Webb’s powerful predecessor.

    The $8.7 billion Webb project, named for a NASA administrator who helped launch the Apollo moon program in the 1960s, began 20 years ago as a collaboration between NASA and the European and Canadian space agencies. The telescope is designed to work for at least five years and has enough fuel to operate for a decade.

    Central to its design is a set of 18 gold-coated mirrors that are sensitive enough to detect the light of a single match struck on the moon. The light is analyzed and recorded by instruments that are protected from the sun’s rays by an umbrella as large as a tennis court.

    Known as a sun shield, the paper-thin layer of plastic keeps the instruments as cool as 400 degrees below zero. “In terms of sunscreen,” Durning said, “the shield has an SPF of about 1 million.”

    And just like an umbrella or a Transformer robot, the sun shield — and the rest of the telescope — folds up, allowing the 15,000-pound Webb to fit snugly inside a rocket.

    Once the Webb is launched, it will take about two weeks for the telescope to unfurl and another two weeks for it to begin orbiting the sun — at a point in space that is a million miles from Earth. By comparison, the Hubble is orbiting about 340 miles from Earth.

    LaGrange Points map. NASA
    LaGrange Points map. NASA Webb will be at L2

    The Webb still needs to undergo final tests and additions. It will be flown to Houston, Texas, in March and eventually shipped to South America for launch from French Guiana.

    Technician Marc Sansebastian will be there to make sure nothing goes wrong. He recently spent four hours inside the telescope, painstakingly applying a small device that will measure the Webb’s movements during a motion test.

    He said that working on something that has cost billions of dollars and years of effort is a little bit stressful, but also exciting. With a tool in hand, he said, stepping inside the Webb is like playing “the ultimate game of Operation.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The James Webb Space Telescope will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for later in the decade.

    Webb telescope will be the premier observatory of the next decade, serving thousands of astronomers worldwide. 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.

    Webb telescope was formerly known as the “Next Generation Space Telescope” (NGST); it was renamed in Sept. 2002 after a former NASA administrator, James Webb.

    Webb is an international collaboration between NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center is managing the development effort. The main industrial partner is Northrop Grumman; the Space Telescope Science Institute will operate Webb after launch.

    Several innovative technologies have been developed for Webb. These include a folding, segmented primary mirror, adjusted to shape after launch; ultra-lightweight beryllium optics; detectors able to record extremely weak signals, microshutters that enable programmable object selection for the spectrograph; and a cryocooler for cooling the mid-IR detectors to 7K.

    There will be four science instruments on Webb: the Near InfraRed Camera (NIRCam), the Near InfraRed Spectrograph (NIRspec), the Mid-InfraRed Instrument (MIRI), and the Fine Guidance Sensor/ Near InfraRed Imager and Slitless Spectrograph (FGS-NIRISS). Webb’s instruments will be designed to work primarily in the infrared range of the electromagnetic spectrum, with some capability in the visible range. It will be sensitive to light from 0.6 to 28 micrometers in wavelength.
    Webb has four main science themes: The End of the Dark Ages: First Light and Reionization, The Assembly of Galaxies, The Birth of Stars and Protoplanetary Systems, and Planetary Systems and the Origins of Life.

    Launch is scheduled for later in the decade on an Ariane 5 rocket. The launch will be from Arianespace’s ELA-3 launch complex at European Spaceport located near Kourou, French Guiana. Webb will be located at the second Lagrange point, about a million miles from the Earth.

    NASA image

    ESA50 Logo large

    Canadian Space Agency

     
  • richardmitnick 3:41 pm on September 28, 2016 Permalink | Reply
    Tags: , , , NASA Webb   

    From Frontier Fields: “Beyond the Frontier Fields: How JWST Will Push the Science to a New Frontier” 

    Frontier Fields
    Frontier Fields

    September 28, 2016
    bonniemeinke

    The Frontier Fields Project has been an ambitious campaign to see deep into our universe. Gravitational lensing, as used by the Frontier Fields Project, enables Hubble to see fainter and more-distant galaxies than would otherwise be possible. These images push to the very limits of how deeply Hubble can see out into space.

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    Hubble, Spitzer, Chandra, and other observatories are doing cutting-edge science through the Frontier Fields Project, but there’s a challenge.

    NASA/Spitzer Telescope
    NASA/Spitzer Telescope

    NASA/Chandra Telescope
    NASA/Chandra Telescope

    Even though leveraging gravitational lensing has allowed astronomers to see objects that otherwise could not be detected with today’s telescopes, the technique still isn’t enough to see the most distant galaxies. As the universe expands, light gets stretched into longer and longer wavelengths, beyond the visible and near-infrared wavelengths Hubble can detect. To see the most distant galaxies, one needs a space telescope with Hubble’s keen resolution, but at infrared wavelengths.

    That infrared telescope is the James Webb Space Telescope, slated to launch in October 2018. It has a mirror 6.5 meters (21 feet) across, can observe wavelengths up to 10 times longer than Hubble can observe, and is the mission that will detect and study the first appearances of galaxies in the universe.

    1
    Figure 1: Webb will have a 6.5-meter-diameter primary mirror, which would give it a significant larger collecting area than the mirrors available on the current generation of space telescopes. Hubble’s mirror is a much smaller 2.4 meters in diameter, and its corresponding collecting area is 4.5 square meters, giving Webb around seven times more collecting area! Webb’s field of view is more than 15 times larger than the NICMOS near-infrared camera on Hubble. It also will have significantly better spatial resolution than is available with the infrared Spitzer Space Telescope. Credit: NASA. http://webbtelescope.org/gallery.

    Observations of the early universe are still incomplete. To build the full cosmological history of our universe, we need to see how the first stars and galaxies formed, and how those galaxies evolved into the grand structures we see today.

    Looking back in time to the first light in the universe:

    Astronomers use light to explore the universe, but there are pieces of our universe’s early history where there wasn’t much light. The era of the universe called the “Dark Ages” is as mysterious as its name implies. Shortly after the Big Bang, our universe was filled with glowing plasma, or ionized gas. As the universe cooled and expanded, electrons and protons began to bind together to form neutral hydrogen atoms (one proton and one electron each). The last of the light from the Big Bang escaped (becoming what we now detect as the Cosmic Microwave Background [CMB]).

    CMB per ESA/Planck
    CMB per ESA/Planck

    The universe would have been a dark place, with no sources of light to reveal this cooling, neutral hydrogen gas.

    Some of that gas would have begun coalescing into dense clumps, pulled together by gravity. As these clumps grew larger, they would become stars and eventually galaxies. Slowly, starlight would begin to shine in the universe. Eventually, as the early stars grew in numbers and brightness, they would have emitted enough ultraviolet light to “reionize” the universe by stripping electrons off neutral hydrogen atoms, leaving behind individual protons. This process created a hot plasma of free electrons and protons. At this point, the light from star and galaxy formation could travel freely across space and illuminate the universe. It is important to note here, astronomers are currently unsure whether the energy responsible for reionization came from stars in the early-forming galaxies; rather, it might have come from hot gas surrounding massive black holes or some even more exotic source such as decaying dark matter.

    The universe’s first stars, believed to be 30 to 300 times as massive as our Sun and millions of times as bright, would have burned for only a few million years before dying in tremendous explosions, or “supernovae.” These explosions spewed the recently manufactured chemical elements of stars outward into the universe before the expiring stars collapsed into black holes.

    Astronomers know the universe became reionized because when they look back at quasars — incredibly bright objects thought to be powered by supermassive black holes — in the distant universe, they don’t see the dimming of their light that would occur if the light passed through a fog of neutral hydrogen gas. While they find clouds of neutral hydrogen gas, they see almost no signs of neutral hydrogen gas in the matter located in the space between galaxies. This means that at some point the matter was reionized. Exactly when this occurred is one of the questions Webb will help answer, by looking for glimpses of very distant objects still dimmed by neutral hydrogen gas.

    Much remains to be uncovered about the time of reionization. The universe right after the Big Bang would have consisted of hydrogen, helium, and a small amount of lithium. But the stars we see today also contain heavier elements — elements that are created inside stars. So how did those first stars form from such limited ingredients? Webb may not be able to see the very first stars of the Dark Ages, but it’ll witness the generation of stars immediately following, and analyze the kinds of materials they contain.

    Webb’s ability to see the infrared light from the most distant objects in the universe will allow it to truly identify the sources that gave rise to reionization. For the first time, we will be able to see the stars and quasars that unleashed enough energy to illuminate the universe again.

    2
    Figure 2: JWST will be able to see back to when the first bright objects (stars and galaxies) were forming in the early universe. Credit: STScI. http://jwst.nasa.gov/firstlight.html

    Early Galaxies:

    Webb will also show us how early galaxies formed from those first clumps of stars. Scientists suspect the black holes born from the explosions of the earliest stars (supernovae) devoured gas and stars around them, becoming the extremely bright objects called “mini-quasars.” The mini-quasars, in turn, may have grown and merged to become the huge black holes found in the centers of present-day galaxies. Webb will try to find and understand these supernovae and mini-quasars to put theories of early galaxy formation to the test. Do all early galaxies have these mini-quasars or only some? These regions give off infrared light as the gas around them cools, allowing Webb to glean information about how mini-quasars in the early universe work — how hot they are, for instance, and how dense.

    Webb will show us whether the first galaxies formed along lines and webs of dark matter, as expected, and when. Right now we know the first galaxies formed anywhere from 378,000 years to 1 billion years after the Big Bang. Many models have been created to explain which era gave rise to galaxies, but Webb will pinpoint the precise time period.

    Hubble is known for its deep-field images, which capture slices of the universe throughout time. But these images stop at the point beyond which Hubble’s vision cannot reach. Webb will fill in the gaps in these images, extending them back to the Dark Ages. Working together, Hubble and Webb will help us visualize much more of the universe than we ever have before, creating for us an unprecedented picture that stretches from the current day to the beginning of the recognizable universe.

    NASA/ESA/CSA Webb Telescope annotated
    NASA/ESA/CSA Webb Telescope annotated
    http://webbtelescope.org/gallery

    Resources:

    https://frontierfields.org/2016/07/21/the-final-frontier-of-the-universe/

    http://hubble25th.org/science/8

    http://webbtelescope.org/article/13

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Frontier Fields draws on the power of massive clusters of galaxies to unleash the full potential of the Hubble Space Telescope. The gravity of these clusters warps and magnifies the faint light of the distant galaxies behind them. Hubble captures the boosted light, revealing the farthest galaxies humanity has ever encountered, and giving us a glimpse of the cosmos to be unveiled by the James Webb Space Telescope.

    NASA Hubble Telescope
    Hubble
    NASA James Webb Telescope
    Webb

     
  • richardmitnick 2:15 pm on July 20, 2016 Permalink | Reply
    Tags: , , NASA Seeks Picometer Accuracy, NASA Webb   

    From Webb: “NASA Seeks Picometer Accuracy” 

    NASA Webb Header

    NASA Webb Telescope

    James Webb Space Telescope

    July 19, 2016
    Lori Keesey
    NASA’s Goddard Space Flight Center

    Team Develops New Tool to Assure Ultra-Stable Space Telescopes

    Finding and characterizing dozens of Earth-like planets will require a super-stable space telescope whose optical components move or distort no more than a few picometers — a measurement smaller than the size of an atom. It also will require next-generation tools with which to assure that level of stability.

    With NASA funding, a team of scientists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, has begun working with an Arizona-based company to develop a highly sophisticated laboratory tool — a high-speed interferometer — capable of assuring picometer-level stability, a feat not yet accomplished.

    1
    At a Goddard cleanroom, technicians unveil the James Webb Observatory’s segmented mirror in preparation for an alignment test this summer. The tool used to determine the segments’ alignment has inspired Goddard technologists to create another that offers picometer accuracy for next-generation observatories. Credits: NASA/Chris Gunn

    New Tool to Assure Picometer-Level Stability

    To help NASA reach this next level of precision, Saif and his Goddard colleague, Lee Feinberg, have begun working with 4-D Technology, of Tucson, Arizona, to develop the instrument.

    Like all interferometers, the instrument would split light and then recombine it to measure tiny changes, including motion. With this tool, technicians would measure distortions in mirror segments, mounts, and other supporting telescope structure primarily during thermal, vibration, and other types of environmental testing.

    Displacements and movement occur when materials used to build the optics shrink or expand due to wildly fluctuating temperatures, such as those experienced when traveling from Earth to the frigidity of space or when exposed to fierce launch forces more than six-and-a-half times the force of gravity.

    If optics must conform to a specific prescription to carry out a challenging mission, even nearly imperceptible, atomic-size movements caused by thermal and dynamic changes could affect their ability to gather and focus enough light to distinguish a planet’s light from that of its parent star — to say nothing of scrutinizing that light to discern different atmospheric chemical signatures, Saif said.

    Leveraging Instrument Developed for Webb Testing

    The effort leverages a similar instrument that 4-D Technology created to test the optics of the Webb Observatory, which will be the most powerful observatory ever built once it launches in October 2018. From its orbit 930,000 miles from Earth, it will study every phase in the history of our universe, from the first luminous glows after the Big Bang to the evolution of our own solar system. Among many other firsts, Webb will carry a 21-foot primary mirror made of 18 separate ultra-lightweight beryllium segments that unfold and adjust to shape after launch.

    To carry out its job, the Webb Observatory also must be highly stable. However, the movement of its materials is measured in nanometers — the unit of measure that scientists use to determine the size of atoms and molecules.

    “What we did was measure the surface of each mirror after each environmental test to see if we could see changes,” Saif said. “I started questioning, what if something behind the mirror moves. Just measuring the surface isn’t enough.”

    To assure nanometer-level stability — 4-D Technology worked with the Webb Observatory team at Goddard to develop a dynamic laser interferometer that instantaneously measured displacements in the mirror segments as well as those in their mounts and other structural components, despite vibration, noise, or air turbulence.

    “The high-speed interferometer actually enables you to do nanometer dynamics for large structures,” Saif said. “This is absolutely new. The instrument is four orders of magnitude more sensitive than other measurement tools and it measures the full surface of the mirrors.” That instrument now is used in laboratories, manufacturing areas, clean rooms, and environmental-testing chambers operated by the project’s major contractors.

    LUVOIR-Type Mission Ups the Ante

    However, a next-generation LUVOIR-type mission will demand even greater stability, and consequently an instrument capable of quickly measuring picometer displacements, which are two orders of a magnitude smaller than an atom. Although it is possible to calculate picometer movements with existing tools, the physics are non-linear and the resulting calculations might not accurately reflect what actually is going on, Saif said.

    “Every subsystem needs to be designed on a picometer level and then tested at picometers,” Saif explained. “You need to measure what you’re interested in and the instrument needs to calculate these motions quickly so that you can understand the dynamics.”

    The team is developing the tool with $1.65 million in funding from NASA’s Cosmic Origins Strategic Astrophysics Technology program. It expects to complete the work in four years.

    For more technology news, go to: http://gsfctechnology.gsfc.nasa.gov/newsletter/Current.pdf

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The James Webb Space Telescope will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for later in the decade.

    Webb telescope will be the premier observatory of the next decade, serving thousands of astronomers worldwide. 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.

    Webb telescope was formerly known as the “Next Generation Space Telescope” (NGST); it was renamed in Sept. 2002 after a former NASA administrator, James Webb.

    Webb is an international collaboration between NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center is managing the development effort. The main industrial partner is Northrop Grumman; the Space Telescope Science Institute will operate Webb after launch.

    Several innovative technologies have been developed for Webb. These include a folding, segmented primary mirror, adjusted to shape after launch; ultra-lightweight beryllium optics; detectors able to record extremely weak signals, microshutters that enable programmable object selection for the spectrograph; and a cryocooler for cooling the mid-IR detectors to 7K.

    There will be four science instruments on Webb: the Near InfraRed Camera (NIRCam), the Near InfraRed Spectrograph (NIRspec), the Mid-InfraRed Instrument (MIRI), and the Fine Guidance Sensor/ Near InfraRed Imager and Slitless Spectrograph (FGS-NIRISS). Webb’s instruments will be designed to work primarily in the infrared range of the electromagnetic spectrum, with some capability in the visible range. It will be sensitive to light from 0.6 to 28 micrometers in wavelength.
    Webb has four main science themes: The End of the Dark Ages: First Light and Reionization, The Assembly of Galaxies, The Birth of Stars and Protoplanetary Systems, and Planetary Systems and the Origins of Life.

    Launch is scheduled for later in the decade on an Ariane 5 rocket. The launch will be from Arianespace’s ELA-3 launch complex at European Spaceport located near Kourou, French Guiana. Webb will be located at the second Lagrange point, about a million miles from the Earth.

    NASA image

    ESA50 Logo large

    Canadian Space Agency

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: