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  • richardmitnick 10:35 am on August 18, 2021 Permalink | Reply
    Tags: "Mapping the Universe's Earliest Structures with COSMOS-Webb", , , , , , NASA/ESA/CSA James Webb Space Telescope, Revolutionizing Our Understanding of the Reionization Era., , University of Texas-Austin (US)   

    From NASA/ESA/CSA James Webb Space Telescope: “Mapping the Universe’s Earliest Structures with COSMOS-Webb” 

    NASA Webb Header

    From NASA/ESA/CSA James Webb Space Telescope

    August 18, 2021

    MEDIA CONTACTS:
    Ann Jenkins
    Space Telescope Science Institute, Baltimore, Maryland

    Christine Pulliam
    Space Telescope Science Institute, Baltimore, Maryland

    1
    About This Image
    The COSMOS-Webb survey will map 0.6 square degrees of the sky—about the area of three full Moons—using the James Webb Space Telescope’s Near Infrared Camera (NIRCam) instrument, while simultaneously mapping a smaller 0.2 square degrees with the Mid Infrared Instrument (MIRI). The jagged edges of the Hubble field’s outline are due to the separate images that make up the survey field. Credits: SCIENCE: National Aeronautics Space Agency (US), European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), Jeyhan Kartaltepe (Rochester Institute of Technology (US))[below], Caitlin Casey (The University of Texas-Austin (US))[below], Anton M. Koekemoer (Space Telescope Science Institute (US))

    Summary

    This ambitious program will study half a million galaxies in a field the size of three full Moons.

    Peering deeply into a huge patch of sky the size of three full Moons, NASA’s James Webb Space Telescope will undertake an ambitious program to study half a million galaxies. Called COSMOS-Webb, this survey is the largest project Webb will undertake during its first year. With more than 200 hours of observing time, it will build upon previous discoveries to make advances in three particular areas of study. These include revolutionizing our understanding of the Reionization Era; looking for early, fully evolved galaxies; and learning how dark matter evolved with galaxies’ stellar content. With its rapid public release of the data, this survey will be a primary legacy dataset from Webb for scientists worldwide studying galaxies beyond the Milky Way.
    ______________________________________________________________________________________________________________

    When NASA’s James Webb Space Telescope begins science operations in 2022, one of its first tasks will be an ambitious program to map the earliest structures in the universe. Called COSMOS-Webb, this wide and deep survey of half-a-million galaxies is the largest project Webb will undertake during its first year.

    With more than 200 hours of observing time, COSMOS-Webb will survey a large patch of the sky—0.6 square degrees—with the Near-Infrared Camera (NIRCam). That’s the size of three full moons. It will simultaneously map a smaller area with the Mid-Infrared Instrument (MIRI).

    “It’s a large chunk of sky, which is pretty unique to the COSMOS-Webb program. Most Webb programs are drilling very deep, like pencil-beam surveys that are studying tiny patches of sky,” explained Caitlin Casey, an assistant professor at the University of Texas at Austin and co-leader of the COSMOS-Webb program. “Because we’re covering such a large area, we can look at large-scale structures at the dawn of galaxy formation. We will also look for some of the rarest galaxies that existed early on, as well as map the large-scale dark matter distribution of galaxies out to very early times.”

    (Dark matter does not absorb, reflect, or emit light, so it cannot be seen directly. We know that dark matter exists because of the effect it has on objects that we can observe.)

    COSMOS-Webb will study half-a-million galaxies with multi-band, high-resolution, near-infrared imaging, and an unprecedented 32,000 galaxies in the mid-infrared. With its rapid public release of the data, this survey will be a primary legacy dataset from Webb for scientists worldwide studying galaxies beyond the Milky Way.

    Building on Hubble’s Achievements

    The COSMOS survey began in 2002 as a Hubble program to image a much larger patch of sky, about the area of 10 full moons. From there, the collaboration snowballed to include most of the world’s major telescopes on Earth and in space. Now COSMOS is a multi-wavelength survey that covers the entire spectrum from the X-ray through the radio.

    Because of its location on the sky, the COSMOS field is accessible to observatories around the world. Located on the celestial equator, it can be studied from both the northern and southern hemispheres, resulting in a rich and diverse treasury of data.

    “COSMOS has become the survey that a lot of extragalactic scientists go to in order to conduct their analyses because the data products are so widely available, and because it covers such a wide area of the sky,” said Rochester Institute of Technology’s Jeyhan Kartaltepe, assistant professor of physics and co-leader of the COSMOS-Webb program. “COSMOS-Webb is the next installment of that, where we’re using Webb to extend our coverage in the near- and mid-infrared part of the spectrum, and therefore pushing out our horizon, how far away we’re able to see.”

    The ambitious COSMOS-Webb program will build upon previous discoveries to make advances in three particular areas of study, including: revolutionizing our understanding of the Reionization Era; looking for early, fully evolved galaxies; and learning how dark matter evolved with galaxies’ stellar content.

    Goal 1: Revolutionizing Our Understanding of the Reionization Era.

    Epoch of Reionization and first stars. Credit: California Institute of Technology (US).

    Soon after the big bang, the universe was completely dark. Stars and galaxies, which bathe the cosmos in light, had not yet formed. Instead, the universe consisted of a primordial soup of neutral hydrogen and helium atoms and invisible dark matter. This is called the cosmic dark ages.

    After several hundred million years, the first stars and galaxies emerged and provided energy to reionize the early universe. This energy ripped apart the hydrogen atoms that filled the universe, giving them an electric charge and ending the cosmic dark ages. This new era where the universe was flooded with light is called the Reionization Era.

    The first goal of COSMOS-Webb focuses on this epoch of reionization, which took place from 400,000 to 1 billion years after the big bang. Reionization likely happened in little pockets, not all at once. COSMOS-Webb will look for bubbles showing where the first pockets of the early universe were reionized. The team aims to map the scale of these reionization bubbles.

    “Hubble has done a great job of finding handfuls of these galaxies out to early times, but we need thousands more galaxies to understand the reionization process,” explained Casey.

    Scientists don’t even know what kind of galaxies ushered in the Reionization Era, whether they’re very massive or relatively low-mass systems. COSMOS-Webb will have a unique ability to find very massive, rare galaxies and see what their distribution is like in large-scale structures. So, are the galaxies responsible for reionization living in the equivalent of a cosmic metropolis, or are they mostly evenly distributed across space? Only a survey the size of COSMOS-Webb can help scientists to answer this.

    Goal 2: Looking for Early, Fully Evolved Galaxies.

    COSMOS-Webb will search for very early, fully evolved galaxies that shut down star birth in the first 2 billion years after the big bang. Hubble has found a handful of these galaxies, which challenge existing models about how the universe formed. Scientists struggle to explain how these galaxies could have old stars and not be forming any new stars so early in the history of the universe.

    With a large survey like COSMOS-Webb, the team will find many of these rare galaxies. They plan detailed studies of these galaxies to understand how they could have evolved so rapidly and turned off star formation so early.

    Goal 3: Learning How Dark Matter Evolved with Galaxies’ Stellar Content.

    COSMOS-Webb will give scientists insight into how dark matter in galaxies has evolved with the galaxies’ stellar content over the universe’s lifetime.

    Galaxies are made of two types of matter: normal, luminous matter that we see in stars and other objects, and invisible dark matter, which is often more massive than the galaxy and can surround it in an extended halo. Those two kinds of matter are intertwined in galaxy formation and evolution. However, presently there’s not much knowledge about how the dark matter mass in the halos of galaxies formed, and how that dark matter impacts the formation of the galaxies.

    COSMOS-Webb will shed light on this process by allowing scientists to directly measure these dark matter halos through “weak lensing.”

    [caption id="attachment_41428" align="alignnone" width="632"] Caterpillar Project A Milky-Way-size dark-matter halo and its subhalos circled, an enormous suite of simulations . Griffen et al. 2016.

    The gravity from any type of mass—whether it’s dark or luminous—can serve as a lens to “bend” the light we see from more distant galaxies. Weak lensing distorts the apparent shape of background galaxies, so when a halo is located in front of other galaxies, scientists can directly measure the mass of the halo’s dark matter.

    “For the first time, we’ll be able to measure the relationship between the dark matter mass and the luminous mass of galaxies back to the first 2 billion years of cosmic time,” said team member Anton Koekemoer, a research astronomer at the Space Telescope Science Institute in Baltimore, who helped design the program’s observing strategy and is in charge of constructing all the images from the program. “That’s a crucial epoch for us to try to understand how the galaxies’ mass was first put in place, and how that’s driven by the dark matter halos. And that can then feed indirectly into our understanding of galaxy formation.”

    Quickly Sharing Data with the Community

    COSMOS-Webb is a Treasury program, which by definition is designed to create datasets of lasting scientific value. Treasury Programs strive to solve multiple scientific problems with a single, coherent dataset. Data taken under a Treasury Program usually has no exclusive access period, enabling immediate analysis by other researchers.

    “As a Treasury Program, you are committing to quickly releasing your data and your data products to the community,” explained Kartaltepe. “We’re going to produce this community resource and make it publicly available so that the rest of the community can use it in their scientific analyses.”

    Koekemoer added, “A Treasury Program commits to making publicly available all these science products so that anyone in the community, even at very small institutions, can have the same, equal access to the data products and then just do the science.”

    COSMOS-Webb is a Cycle 1 General Observers program. General Observers programs were competitively selected using a dual-anonymous review system, the same system that is used to allocate time on Hubble.

    From Rochester Institute of Technology (US)

    James Webb Space Telescope program aims to map the earliest structures of the universe
    COSMOS-Webb is slated to be the largest program in JWST’s first year of operation.

    April 19, 2021
    Luke Auburn
    luke.auburn@rit.edu

    3
    RIT Assistant Professor Jeyhan Kartaltepe is the principal investigator of COSMOS-Webb, the largest General Observer program selected for James Webb Space Telescope’s first year. Credit: A. Sue Weisler.

    When the James Webb Space Telescope (JWST)—the long-awaited successor to the Hubble Space Telescope—becomes operational in 2022, one of its first orders of business will be mapping the earliest structures of the universe. A team of nearly 50 researchers led by scientists at Rochester Institute of Technology and University of Texas at Austin will attempt to do so through the COSMOS-Webb program, the largest General Observer program selected for JWST’s first year.

    Over the course of 208.6 observing hours, the COSMOS-Webb program will conduct an ambitious survey of half a million galaxies with multi-band, high-resolution near infrared imaging and an unprecedented 32,000 galaxies in mid infrared. The scientists involved said that because COSMOS-Webb is a treasury program, they will rapidly release data to the public so it can lead to countless other studies by other researchers.

    “The sheer scope of our program is so exciting,” said principal investigator Jeyhan Kartaltepe, an assistant professor in RIT’s School of Physics and Astronomy. “The first year of Webb observations will result in a lot of new discoveries that people will want explore more in-depth in future cycles. I think the public legacy of COSMOS-Webb will be that COSMOS will be the field where the community conducts this type of follow-up research.”

    Caitlin Casey, an assistant professor and principal investigator at UT Austin, said “COSMOS-Webb has the potential to be ground-breaking in ways we haven’t even dreamt yet. You don’t know what treasures are there to find until you use an incredible telescope like Webb to stare at the sky for a long time.”

    The survey will map 0.6 square degrees of the sky—about the area of three full moons—using JWST’s Near Infrared Camera (NIRCam) instrument while simultaneously mapping a smaller area of 0.2 square degrees with the Mid Infrared Instrument (MIRI). Through this approach, the scientists hope to achieve three main goals [above].

    “A key result from the original HST-COSMOS effort over a decade ago was showing that dark matter is the cosmic scaffolding upon which the structures in the universe we see today are formed,” said Rhodes. “COSMOS-Webb will make use of the JWST’s larger mirror to push that dark matter mapping farther in time and to higher resolution maps, allowing us to study how dark matter has influenced the evolution of individual galaxies from the early universe to now.”

    COSMOS-Webb is one of just 286 General Scientific Observer programs selected out of more than 1,000 proposals for the telescope’s first year of science, known as Cycle 1. These specific programs will provide the worldwide astronomical community with one of the first extensive opportunities to investigate scientific targets with Webb. NASA is currently targeting Oct. 31, 2021, for JWST’s launch.

    For more information about COSMOS-Webb, go to the Space Telescope Science Institute website.

    From University of Texas-Austin (US)

    20 April 2021
    Rebecca A Johnson

    Texas Astronomers Lead Major Projects in James Webb Space Telescope’s First Year

    4
    Caitlin Casey

    Astronomers at The University of Texas at Austin are set to lead some of the largest programs in the first year of NASA’s James Webb Space Telescope (JWST), including the largest project overall. Set to launch this Halloween, the telescope will become operational by mid-2022. Altogether, UT astronomers received about 500 hours of telescope time in JWST’s first year.

    COSMOS-Webb, a project to map the earliest structures of the universe, is the largest project JWST will undertake in 2022. UT’s Caitlin Casey, assistant professor of astronomy, leads an international team of nearly 50 researchers, along with co-leader Jeyhan Kartaltepe of the Rochester Institute of Technology.

    With more than 200 hours of observing time, COSMOS-Webb will conduct an ambitious survey of half a million galaxies. As a “treasury program,” the team will rapidly release their data to the public for use by other researchers.

    Casey explained that their project will “stare deeply over a large patch of sky, about three times the size of the Moon. Instead of just finding the most distant galaxies, we hope to find them and figure out where they live in the universe, whether it be an ancient cosmic metropolis or a distant cosmic outpost.”

    In probing the galaxies’ habitats, they are looking for bubbles showing where the first pockets of the early universe were reionized — that is, when light from the first stars and galaxies ripped apart hydrogen atoms that filled the cosmos, giving them an electric charge. This ended the cosmic dark ages, and began a new era where the universe was flooded with light, called the epoch of reionization. COSMOS-Webb hopes to map the scale of these reionization bubbles.

    “COSMOS-Webb has the potential to be ground-breaking in ways we haven’t even dreamt yet,” Casey said. “You don’t know what treasures are there to find until you use an incredible telescope like Webb to stare at the sky for a long time.”

    Another major first-year JWST project is led by UT associate professor Steven Finkelstein. The fourth-largest project the telescope will undertake in 2022, it’s called the Webb Deep Extragalactic Exploratory Public (WDEEP) Survey. Finkelstein co-leads a large team along with Casey Papovich of Texas A&M University and Nor Pirzkal of the Space Telescope Science Institute.

    In some ways, WDEEP is similar to COSMOS-Webb, Finkelstein said. Both are studying early galaxies, but at different early epochs in the history of the universe.

    “Together, the projects COSMOS-Webb and WDEEP are bracketing the epoch of reionization,” Finkelstein said. “So with WDEEP, we’re trying to push to the very beginning of reionization when the earliest galaxies really started to form stars, and begin to ionize the intergalactic medium. Whereas Professor Casey’s program is targeting the end of reionization, looking at the descendants of our galaxies and the bubbles they have created around them.”

    In terms of how the projects will be carried out, though, “WDEEP is almost the exact opposite,” Finkelstein said. “While COSMOS-Webb is going very wide to look for the brightest and most massive galaxies, WDEEP is going deep. We are going to pick one place in the sky and stare at it for over 100 hours, following in the footsteps of the original Hubble Deep Field,” he said.

    He explained that the goal of WDEEP is to push the frontier in terms of the most distant galaxies detected. The team expects to find 50 or more galaxies at a time less than 500 million years after the Big Bang, which is “a completely unexplored epoch” in the universe’s history, he said. And if they’re lucky, they might find a galaxy at just 270 million years after the Big Bang, or 2% of the universe’s present age of 13.8 billion years.

    The goal in finding these most-distant galaxies is to help understand the early universe. “There are a wide range of theoretical predictions for what the universe should look like at these times,” Finkelstein said. “Without observations, these predictions are completely unconstrained. Our goal is to try and pin down those models telling us what the earliest galaxies were like.”

    Other UT astronomers lead or co-lead JWST first-year projects on a variety of topics. These include faculty members Brendan Bowler, John Chisholm, Harriet Dinerstein, Neal Evans, and Caroline Morley; postdoctoral researchers Micaela Bagley, Will Best, and Justin Spilker; and graduate student Samuel Factor. The projects include studies of planet formation, the failed stars called brown dwarfs, the chemistry of pre-biotic molecules in newly forming stars, early stages of star formation, the dead stars called planetary nebulae, the formation of massive galaxies in the early universe, and more. Together, they will use about 100 hours of telescope time in the telescope’s first year.

    From California Institute of Technology (US)

    April 19, 2021
    COSMOS-Webb selected as JWST’s largest Cycle 1 program

    When the James Webb Space Telescope (JWST)—the long-awaited successor to the Hubble Space Telescope—becomes operational in 2022, one of its first orders of business will be mapping the earliest structures of the universe. A team of nearly 50 researchers led by scientists at Rochester Institute of Technology [above] and University of Texas at Austin [above] will attempt to do so through the COSMOS-Webb program, the largest General Observer program selected for JWST’s first year.

    Over the course of 208.6 observing hours, the COSMOS-Webb program will conduct an ambitious survey of half a million galaxies with multi-band, high-resolution near infrared imaging and an unprecedented 32,000 galaxies in mid infrared. The scientists involved said that because COSMOS-Webb is a treasury program, they will rapidly release data to the public so it can lead to countless other studies by other researchers.

    “The sheer scope of our program is so exciting,” said principal investigator Jeyhan Kartaltepe, an assistant professor at RIT. “The first year of Webb observations will result in a lot of new discoveries that people will want explore more in-depth in future cycles. I think the public legacy of COSMOS-Webb will be that COSMOS will be the field where the community conducts this type of follow-up research.”

    Caitlin Casey, an assistant professor and principal investigator at UT Austin, said “COSMOS-Webb has the potential to be ground-breaking in ways we haven’t even dreamt yet. You don’t know what treasures are there to find until you use an incredible telescope like Webb to stare at the sky for a long time.”

    The survey will map 0.6 square degrees of the sky—about the area of three full moons—using JWST’s Near Infrared Camera (NIRCam) [above] instrument while simultaneously mapping a smaller area of 0.2 square degrees with the Mid Infrared Instrument (MIRI) [above]. Through this approach, the scientists hope to achieve three main goals.

    The first goal focuses on the epoch of reionization [above], which took place from 400,000 to 1 billion years after the big bang. When the first stars and galaxies formed, they provided energy to re-ionize the early universe and it likely happened in little pockets, not all at once. COSMOS-Webb aims to map out the scale of these reionization bubbles.

    “At these early epochs, COSMOS-Webb will reveal thousands of galaxies, fainter, more distant and more numerous than those previously discovered with Hubble”, said Anton Koekemoer, a research astronomer in the Webb team at the Space Telescope Science Institute, who helped design the observing strategy for the program.

    A second goal is to use the MIRI instrument to look for fully evolved galaxies at high redshifts that seemingly matured soon after the universe formed. Hubble Space Telescope (HST) has found examples of these galaxies, which challenge existing models about how the universe formed, so the hope is to find more examples of these high redshift galaxies and study them in more detail to understand how they could have evolved so rapidly.

    The third primary objective makes use of a technique called weak lensing [above]. Because gravity is sensitive to all kinds of matter including that we cannot see, scientists can use the distortions of light around galaxies to estimate of the amount of dark matter. Jason Rhodes, a senior research scientist at NASA’s Jet Propulsion Laboratory, said COSMOS-Webb will provide important insight about how dark matter in galaxies has evolved with the stellar content of galaxies over the age of the universe.

    “A key result from the original HST-COSMOS effort over a decade ago was showing that dark matter is the cosmic scaffolding upon which the structures in the universe we see today are formed,” said Rhodes. “COSMOS-Webb will make use of the JWST’s larger mirror to push that dark matter mapping farther in time and to higher resolution maps, allowing us to study how dark matter has influenced the evolution of individual galaxies from the early universe to now.”

    COSMOS-Webb is one of just 286 General Scientific Observer programs selected out of more than 1,000 proposals for the telescope’s first year of science, known as Cycle 1. These specific programs will provide the worldwide astronomical community with one of the first extensive opportunities to investigate scientific targets with Webb. NASA is currently targeting Oct. 31, 2021, for JWST’s launch.

    The COSMOS-Webb team is made up of 49 astronomers worldwide, including 31 based at US-institutes, 18 at international institutes, and 13 students and postdocs. See the coordinated press release at several institutes, including RIT [above], UT Austin [above], University of California-Santa Cruz (US), University of Durham, University of Bologna [Alma mater studiorum – Università di Bologna](IT), MPG Institute for Astronomy [MPG Institut für Astronomie](DE), Kavli Institute for the Physics and Mathematics of the Universe (JP)-University of Tokyo[(東京大] (JP), and DAWN – University of Copenhagen [Københavns Universitet](DK).

    See the full article here .

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    Stem Education Coalition

    The NASA/ESA/CSA James Webb Space Telescope will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for October 2021.

    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 National Aeronautics and Space Administration (US), the European Space Agency (ESA), and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center (US) is managing the development effort. The main industrial partner is Northrop Grumman; the Space Telescope Science Institute (US) 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.

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  • richardmitnick 10:50 am on June 23, 2021 Permalink | Reply
    Tags: "NASA’s Webb Will Use Quasars to Unlock the Secrets of the Early Universe", , , , , NASA/ESA/CSA James Webb Space Telescope   

    From NASA/ESA/CSA James Webb Space Telescope: “NASA’s Webb Will Use Quasars to Unlock the Secrets of the Early Universe” 

    NASA Webb Header

    From NASA/ESA/CSA James Webb Space Telescope

    June 23, 2021

    Ann Jenkins
    Space Telescope Science Institute, Baltimore, Maryland

    Christine Pulliam
    Space Telescope Science Institute, Baltimore, Maryland

    Laura Betz
    NASA Goddard Space Flight Center, Greenbelt, Maryland

    1
    About This Image

    This is an artist’s concept of a galaxy with a brilliant quasar at its center. A quasar is a very bright, distant and active supermassive black hole that is millions to billions of times the mass of the Sun. Among the brightest objects in the universe, a quasar’s light outshines that of all the stars in its host galaxy combined. Quasars feed on infalling matter and unleash torrents of winds and radiation, shaping the galaxies in which they reside. Using the unique capabilities of Webb, scientists will study six of the most distant and luminous quasars in the universe. Credits: ARTWORK: Joseph Olmsted National Aeronautics Space Agency (US), European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), (Space Telescope Science Institute (US))

    Summary:
    Looking back in time, Webb will see quasars as they appeared billions of years ago.

    Outshining all the stars in their host galaxies combined, quasars are among the brightest objects in the universe. These brilliant, distant and active supermassive black holes shape the galaxies in which they reside. Shortly after its launch, scientists will use Webb to study six of the most far-flung and luminous quasars, along with their host galaxies, in the very young universe. They will examine what part quasars play in galaxy evolution during these early times. The team will also use the quasars to study the gas in the space between galaxies in the infant universe. Only with Webb’s extreme sensitivity to low levels of light and its superb angular resolution will this be possible.

    ______________________________________________________________________________________________________________

    Quasars are very bright, distant and active supermassive black holes that are millions to billions of times the mass of the Sun. Typically located at the centers of galaxies, they feed on infalling matter and unleash fantastic torrents of radiation. Among the brightest objects in the universe, a quasar’s light outshines that of all the stars in its host galaxy combined, and its jets and winds shape the galaxy in which it resides.

    Shortly after its launch later this year, a team of scientists will train NASA’s James Webb Space Telescope on six of the most distant and luminous quasars. They will study the properties of these quasars and their host galaxies, and how they are interconnected during the first stages of galaxy evolution in the very early universe. The team will also use the quasars to examine the gas in the space between galaxies, particularly during the period of cosmic reionization , which ended when the universe was very young. They will accomplish this using Webb’s extreme sensitivity to low levels of light and its superb angular resolution.
    Webb: Visiting the Young Universe

    As Webb peers deep into the universe, it will actually look back in time. Light from these distant quasars began its journey to Webb when the universe was very young and took billions of years to arrive. We will see things as they were long ago, not as they are today.

    “All these quasars we are studying existed very early, when the universe was less than 800 million years old, or less than 6 percent of its current age. So these observations give us the opportunity to study galaxy evolution and supermassive black hole formation and evolution at these very early times,” explained team member Santiago Arribas, a research professor at the Department of Astrophysics of the Centro de Astrobiología (CAB, CSIC-INTA) (ES) , Spain. Arribas is also a member of Webb’s Near-Infrared Spectrograph (NIRSpec
    ) Instrument Science Team.

    The light from these very distant objects has been stretched by the expansion of space. This is known as cosmological redshift. The farther the light has to travel, the more it is redshifted. In fact, the visible light emitted at the early universe is stretched so dramatically that it is shifted out into the infrared when it arrives to us. With its suite of infrared-tuned instruments, Webb is uniquely suited to studying this kind of light.

    Studying Quasars, Their Host Galaxies and Environments, and Their Powerful Outflows

    The quasars the team will study are not only among the most distant in the universe, but also among the brightest. These quasars typically have the highest black hole masses, and they also have the highest accretion rates — the rates at which material falls into the black holes.

    “We’re interested in observing the most luminous quasars because the very high amount of energy that they’re generating down at their cores should lead to the largest impact on the host galaxy by the mechanisms such as quasar outflow and heating,” said Chris Willott, a research scientist at the Herzberg Astronomy and Astrophysics Research Centre of the National Research Council of Canada (NRC) (CA) in Victoria, British Columbia. Willott is also the Canadian Space Agency [Agence Spatiale Canadienne](CA)’s Webb project scientist. “We want to observe these quasars at the moment when they’re having the largest impact on their host galaxies.”

    An enormous amount of energy is liberated when matter is accreted by the supermassive black hole. This energy heats and pushes the surrounding gas outward, generating strong outflows that tear across interstellar space like a tsunami, wreaking havoc on the host galaxy.

    Outflows play an important role in galaxy evolution. Gas fuels the formation of stars, so when gas is removed due to outflows, the star-formation rate decreases. In some cases, outflows are so powerful and expel such large amounts of gas that they can completely halt star formation within the host galaxy. Scientists also think that outflows are the main mechanism by which gas, dust and elements are redistributed over large distances within the galaxy or can even be expelled into the space between galaxies – the intergalactic medium. This may provoke fundamental changes in the properties of both the host galaxy and the intergalactic medium.

    Examining Properties of Intergalactic Space During the Era of Reionization

    More than 13 billion years ago, when the universe was very young, the view was far from clear. Neutral gas between galaxies made the universe opaque to some types of light. Over hundreds of millions of years, the neutral gas in the intergalactic medium became charged or ionized, making it transparent to ultraviolet light. This period is called the Era of Reionization.

    But what led to the reionization that created the “clear” conditions detected in much of the universe today? Webb will peer deep into space to gather more information about this major transition in the history of the universe. The observations will help us understand the Era of Reionization, which is one of the key frontiers in astrophysics.

    The team will use quasars as background light sources to study the gas between us and the quasar. That gas absorbs the quasar’s light at specific wavelengths. Through a technique called imaging spectroscopy, they will look for absorption lines in the intervening gas. The brighter the quasar is, the stronger those absorption line features will be in the spectrum. By determining whether the gas is neutral or ionized, scientists will learn how neutral the universe is and how much of this reionization process has occurred at that particular point in time.

    “If you want to study the universe, you need very bright background sources. A quasar is the perfect object in the distant universe, because it’s luminous enough that we can see it very well,” said team member Camilla Pacifici, who is affiliated with the Canadian Space Agency but works as an instrument scientist at the Space Telescope Science Institute in Baltimore. “We want to study the early universe because the universe evolves, and we want to know how it got started.”

    The team will analyze the light coming from the quasars with NIRSpec to look for what astronomers call “metals,” which are elements heavier than hydrogen and helium. These elements were formed in the first stars and the first galaxies and expelled by outflows. The gas moves out of the galaxies it was originally in and into the intergalactic medium. The team plans to measure the generation of these first “metals,” as well as the way they’re being pushed out into the intergalactic medium by these early outflows.

    The Power of Webb

    Webb is an extremely sensitive telescope able to detect very low levels of light. This is important, because even though the quasars are intrinsically very bright, the ones this team is going to observe are among the most distant objects in the universe. In fact, they are so distant that the signals Webb will receive are very, very low. Only with Webb’s exquisite sensitivity can this science be accomplished. Webb also provides excellent angular resolution, making it possible to disentangle the light of the quasar from its host galaxy.

    The quasar programs described here are Guaranteed Time Observations
    involving the spectroscopic capabilities of NIRSpec.

    The James Webb Space Telescope will be the world’s premier space science observatory when it launches in 2021. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The NASA/ESA/CSA James Webb Space Telescope will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for October 2021.

    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 National Aeronautics and Space Administration (US), the European Space Agency (ESA), and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center (US) is managing the development effort. The main industrial partner is Northrop Grumman; the Space Telescope Science Institute (US) 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.

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  • richardmitnick 10:24 am on May 19, 2021 Permalink | Reply
    Tags: "Webb to Study How Massive Stars' Blasts of Radiation Influence Their Environments", , , , , NASA/ESA/CSA James Webb Space Telescope   

    From NASA/ESA/CSA James Webb Space Telescope: “Webb to Study How Massive Stars’ Blasts of Radiation Influence Their Environments” 

    NASA Webb Header

    From NASA/ESA/CSA James Webb Space Telescope

    May 19, 2021

    MEDIA CONTACT:
    Ann Jenkins
    Space Telescope Science Institute, Baltimore, Maryland

    Christine Pulliam
    Space Telescope Science Institute, Baltimore, Maryland

    1
    Orion Bar.
    About This Image
    The Orion Bar is a diagonal, ridge-like feature of gas and dust in the lower left quadrant of this image of the Orion Nebula. Sculpted by the intense radiation from nearby hot, young stars, the Orion Bar at first glance appears to be shaped like a bar. It is probably prototypical of a photodissociation region, or PDR.
    Credits: SCIENCE: NASA, ESA, Massimo Robberto (STScI, ESA), Hubble Space Telescope Orion Treasury Project Team
    IMAGE PROCESSING: Alyssa Pagan (STScI)

    2
    Anatomy of a Photodissociation Region
    About This Image
    This graphic depicts the stratified nature of a photodissociation region (PDR) such as the Orion Bar. Once thought to be homogenous areas of warm gas and dust, PDRs are now known to contain complex structure and four distinct zones. The box at the left shows a portion of the Orion Bar within the Orion Nebula. The box at the top right illustrates a massive star-forming region whose blasts of ultraviolet radiation are affecting a PDR. The box at the bottom right zooms in on a PDR to depict its four, distinct zones: 1) the molecular zone, a cold and dense region where the gas is in the form of molecules and where stars could form; 2) the dissociation front, where the molecules break apart into atoms as the temperature rises; 3) the ionization front, where the gas is stripped of electrons, becoming ionized, as the temperature increases dramatically; and 4) the fully ionized flow of gas into a region of atomic, ionized hydrogen. For the first time, Webb will be able to separate and study these different zones’ physical conditions. Credits: ILLUSTRATION: NASA, ESA, CSA, Jason Champion (National Centre for Scientific Research [Centre national de la recherche scientifique, [CNRS] (FR)), Pam Jeffries (STScI), PDRs4ALL ERS Team.

    Summary
    The nearby Orion Bar is a typical example of a region influenced by young, massive stars.

    Spectacular supernova explosions have been known to shape the structure of galaxies for a long time. But recently, scientists have discovered that massive stars influence their environments throughout their lifetimes — not only when they go supernova. In the Orion Nebula — a nearby stellar nursery — young, massive stars are flooding their birth clouds with ultraviolet radiation.

    One such region within the nebula where this is happening is the Orion Bar, a ridge-like feature of gas and dust that is being sculpted by the intense radiation from neighboring hot, young stars. In reality, the Orion Bar is not really a “bar” at all. Instead, it contains a lot of structure and several distinct zones. For the first time, Webb will be able to separate and study these different zones’ physical conditions.
    ______________________________________________________________________________________________________________

    In a nearby stellar nursery called the Orion Nebula, young, massive stars are blasting far-ultraviolet light at the cloud of dust and gas from which they were born. This intense flood of radiation is violently disrupting the cloud by breaking apart molecules, ionizing atoms and molecules by stripping their electrons, and heating the gas and dust. An international team using NASA’s James Webb Space Telescope, which is scheduled to launch in October, will study a portion of the radiated cloud called the Orion Bar to learn more about the influence massive stars have on their environments, and even on the formation of our own solar system.

    “The fact that massive stars shape the structure of galaxies through their explosions as supernovas has been known for a long time. But what people have discovered more recently is that massive stars also influence their environments not only as supernovas, but through their winds and radiation during their lives,” said one of the team’s principal investigators, Olivier Berné, a research scientist at the French National Centre for Scientific Research in Toulouse.

    Why the Orion Bar?

    While it might sound like a Friday-night watering hole, the Orion Bar is actually a ridge-like feature of gas and dust within the spectacular Orion Nebula.

    A little more than 1,300 light-years away, this nebula is the nearest region of massive star formation to the Sun. The Orion Bar is sculpted by the intense radiation from nearby, hot, young stars, and at first glance appears to be shaped like a bar. It is a “photodissociation region,” or PDR, where ultraviolet light from young, massive stars creates a mostly neutral, but warm, area of gas and dust between the fully ionized gas surrounding the massive stars and the clouds in which they are born. This ultraviolet radiation strongly influences the gas chemistry of these regions and acts as the most important source of heat.

    PDRs occur where interstellar gas is dense and cold enough to remain neutral, but not dense enough to prevent the penetration of far-ultraviolet light from massive stars. Emissions from these regions provide a unique tool to study the physical and chemical processes that are important for most of the mass between and around stars. The processes of radiation and cloud disruption drive the evolution of interstellar matter in our galaxy and throughout the universe from the early era of vigorous star formation to the present day.

    “The Orion Bar is probably the prototype of a PDR,” explained Els Peeters, another of the team’s principal investigators. Peeters is a professor at the University of Western Ontario and a member of the SETI Institute. “It’s been studied extensively, so it’s well characterized. It’s very close by, and it’s really seen edge on. That means you can probe the different transition regions. And since it’s close by, this transition from one region to another is spatially distinct if you have a telescope with high spatial resolution.”

    The Orion Bar is representative of what scientists think were the harsh physical conditions of PDRs in the universe billions of years ago. “We believe that at this time, you had ‘Orion Nebulas’ everywhere in the universe, in many galaxies,” said Berné. “We think that it can be representative of the physical conditions in terms of the ultraviolet radiation field in what are called ‘starburst galaxies,’ which dominate the era of star formation, when the universe was about half its current age.”

    The formation of planetary systems in interstellar regions irradiated by massive young stars remains an open question. Detailed observations would allow astronomers to understand the impact of the ultraviolet radiation on the mass and composition of newly formed stars and planets.

    In particular, studies of meteorites suggest that the solar system formed in a region similar to the Orion Nebula. Observing the Orion Bar is a way to understand our past. It serves as a model to learn about the very early stages of the formation of the solar system.

    Like a Layer Cake in Space

    PDRs were long thought to be homogenous regions of warm gas and dust. Now scientists know they are greatly stratified, like a layer cake. In reality, the Orion Bar is not really a “bar” at all. Instead, it contains a lot of structure and four distinct zones. These are:

    · The molecular zone, a cold and dense region where the gas is in the form of molecules and where stars could form;

    · The dissociation front, where the molecules break apart into atoms as the temperature rises;

    · The ionization front, where the gas is stripped of electrons, becoming ionized, as the temperature increases dramatically;

    · The fully ionized flow of gas into a region of atomic, ionized hydrogen.

    “With Webb, we will be able to separate and study the different regions’ physical conditions, which are completely different,” said Emilie Habart, another of the team’s principal investigators. Habart is a scientist with the French Institute of Space Astrophysics and a senior lecturer at Paris-Saclay University. “We will study the passage from very hot regions to very cold ones. This is the first time we will be able to do that.”

    The phenomenon of these zones is much like what happens with heat from a fireplace. As you move away from the fire, the temperature drops. Similarly, the radiation field changes with distance from a massive star. In the same way, the composition of the material changes at different distances from that star. With Webb, scientists for the first time will resolve each individual region within that layered structure in the infrared and characterize it completely.

    Paving the Way for Future Observations

    These observations will be part of the Director’s Discretionary-Early Release Science
    program, which provides observing time to sel ected projects early in the telescope’s mission. This program allows the astronomical community to quickly learn how best to use Webb’s capabilities, while also yielding robust science.

    One goal of the Orion Bar work is to identify the characteristics that will serve as a “template” for future studies of more distant PDRs. At greater distances, the different zones might blur together. Information from the Orion Bar will be useful for interpreting that data. The Orion Bar observations will be available to the wider science community very soon after their collection.

    “Most of the light that we receive from very distant galaxies is coming from ‘Orion Nebulas’ situated in these galaxies,” explained Berné. “So it makes a lot of sense to observe in great detail the Orion Nebula that is near us in order to then understand the emissions coming from these very distant galaxies that contain many Orion-like regions in them.”

    Only Possible with Webb

    With its location in space, infrared capability, sensitivity, and spatial resolution, Webb provides a unique opportunity to study the Orion Bar. The team will probe this region using Webb’s cameras and spectrographs.

    “It’s really the first time that we have such good wavelength coverage and angular resolution,” said Berné. “We’re very interested in spectroscopy because that’s where you see all the ‘fingerprints’ that give you the detailed information on the physical conditions. But we also want the images to see the structure and organization of matter. When you combine the spectroscopy and the imaging in this unique infrared range, you get all the information you need to do the science we’re interested in.”

    The study includes a core team of 20 members but also a large, international, interdisciplinary team of more than 100 scientists from 18 countries. The group includes astronomers, physicists, chemists, theoreticians, and experimentalists.

    The James Webb Space Telescope will be the world’s premier space science observatory when it launches in 2021. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The NASA/ESA/CSA James Webb Space Telescope will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for October 2021.

    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 National Aeronautics and Space Administration (US), the European Space Agency (ESA), and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center (US) is managing the development effort. The main industrial partner is Northrop Grumman; the Space Telescope Science Institute (US) 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.

    ESA50 Logo large

    Canadian Space Agency

     
  • richardmitnick 10:54 am on February 6, 2021 Permalink | Reply
    Tags: "JADES will go deeper than the Hubble Deep Fields", , , , , , , In the case of light we perceive changes in wave frequency as changes in color not changes in pitch., , It took 11.3 days for the Hubble Space Telescope to collect these ancient photons for the Hubble Ultra Deep Field image., JADES- James Webb Space Telescope Advanced Deep Extragalactic Survey., LaGrange Points via NASA, , NASA/ESA/CSA James Webb Space Telescope, , The Hubble Ultra Deep Field, The infrared Spitzer Space Telescope which recently went into retirement., The main goal is to see far away in space – and thus far back into the very young universe – and image it just at the end of the so-called Cosmic Dark Ages., To conduct the new survey the Webb telescope will be staring at a small point of space for nearly 800 hours., Webb will be able to image-in infrared at the same resolution-detail -that Hubble could obtain in the optical part of the spectrum.   

    From EarthSky: “JADES will go deeper than the Hubble Deep Fields” 

    1

    From EarthSky

    January 31, 2021 [Just this morning in social media.]
    Theresa Wiegert

    Astronomers announced this month that a new deep-field survey called JADES will be carried out with the James Webb Space Telescope, Hubble’s much-anticipated successor. The Webb is due to launch later this year.

    NASA/ESA/CSA James Webb Space Telescope annotated.

    1
    The Hubble Ultra Deep Field (in its eXtreme version) is the deepest view of the universe yet obtained … and will be, until JADES takes over. It stretches approximately 13 billion light-years and includes approximately 10,000 galaxies. It took 11.3 days for the Hubble Space Telescope to collect these ancient photons. We’re seeing these galaxies as they were billions of years ago. How might they look today? Credit: NASA/ ESA/ S. Beckwith (STScI)/ HUDF team.

    Astronomers announced a new deeper-than-ever sky survey this month (January 15, 2021), to be conducted with the James Webb Space Telescope, the Hubble telescope’s successor, scheduled for launch in October of this year. The new survey is abbreviated JADES, which is short for James Webb Space Telescope Advanced Deep Extragalactic Survey. The survey will be like the Hubble Deep Fields, but deeper still. Its main goal is to see far away in space – and thus far back into the very young universe – and image it just at the end of the so-called , that is, at the time when gas in the universe went from being opaque to transparent. This is also the time when the very first stars were forming – very large, massive and bright stars – in a veritable firestorm of star birth when the young universe was less than 5% of its current age.

    2
    Milestones in the history of the universe (not to scale). Gas was in a neutral state from about 300,000 years after the Big Bang until light from the first generation of stars and galaxies began to ionize it, that is, strip atoms in the gas of their electrons. A new study examines the universe at 800 million years (yellow box) to investigate when and how this transformation occurred. Image via NAOJ/NOIRLab NOAO.

    4
    Webb will be able to see back to when the first bright objects (stars and galaxies) were forming in the early universe. Credit: STScI.

    The Webb telescope will be located near the second Lagrange point – a relatively stable region of space, gravitationally speaking, known as L2 – some 930,000 miles (1.5 million km) from Earth.

    LaGrange Points map. NASA.

    To conduct the new survey, the Webb telescope will be staring at a small point of space for nearly 800 hours (approximately 33 days) to be able to see fainter objects than those ever seen before and thus to find the first generation of galaxies. Astronomers want to know, among other things, how fast did these galaxies form, and how fast did their stars form? They also want to look for the very first supermassive black holes, which are thought to lie at the hearts of nearly all large galaxies, including our Milky Way.

    The long-anticipated launch of the James Webb Space Telescope has been postponed a number of times for a variety of reasons, most recently because of effects of the Covid-19 pandemic. It is the formal successor to the Hubble Space Telescope, but is equipped with instrumentation able to image further into the infrared part of the electromagnetic spectrum than Hubble could.

    This capability also makes it a worthy successor to the infrared Spitzer Space Telescope which recently went into retirement.

    NASA/Spitzer Infrared telescope no longer in service. Launched in 2003 and retired on 30 January 2020. Credit: NASA.

    What makes the infrared part of the spectrum so important for surveys like JADES? If you look really deep, you will also look back in time, and the farther back in time you look, the more redshifted the galaxies are (the farther away they are, the faster they move away from us, and the more their light has been shifted towards the red part of the spectrum).

    5
    Redshift. Credit: Wikimedia Commons.

    Astronomers use redshifts to measure how the universe is expanding, and thus to determine the distance to our universe’s most distant (and therefore oldest) objects. What is a redshift? It’s often compared to the high-pitched whine of an ambulance siren coming at you, which drops in pitch as the ambulance moves past you and then away from you. That change in the sound of an ambulance is due to what’s called the Doppler effect. It’s a good comparison because both sound and light travel in waves, which are affected by their movement through air and space.

    Sound can only move so fast through the air; sound travels at about 750 miles (1,200 kilometers) per hour. As an ambulance races forward and blares its siren, the sound waves in front of the ambulance get squished together. Meanwhile, the sound waves behind the ambulance get spread out. This means the frequency of the sound waves is higher ahead of the ambulance (more sound waves will strike a listener’s ear, over a set amount of time) and lower behind it (fewer sound waves will strike a listener’s ear, over a set amount of time). Our brains interpret changes in the frequency of sound waves as changes in pitch.

    Like sound, light is also a wave traveling at a fixed speed: 186,000 miles (300,000 km) per second, or some one billion kilometers per hour. Light, therefore, plays by similar rules as sound.

    But, in the case of light, we perceive changes in wave frequency as changes in color, not changes in pitch.

    This means that the light we want to observe, originally in the optical (visible) part of the electromagnetic spectrum, might not even show much in the optical part anymore. Instead, it’s been shifted to longer wavelengths, into the infrared regime.

    In other words, the use of infrared cameras is necessary to be able to see the light from the first generation of galaxies. Daniel Eisenstein, a professor of astronomy at Harvard University, said:

    “Galaxies, we think, begin building up in the first billion years after the Big Bang, and sort of reach adolescence at 1 to 2 billion years. We’re trying to investigate those early periods. We must do this with an infrared-optimized telescope because the expansion of the universe causes light to increase in wavelength as it traverses the vast distance to reach us. So even though the stars are emitting light primarily in optical and ultraviolet wavelengths, that light is shifted quite relentlessly out into the infrared. Only Webb can get to the depth and sensitivity that’s needed to study these early galaxies.”

    In fact, the James Webb Space Telescope was built specifically for this purpose. Up to now, infrared images are much less resolved – less clear – than optical images, because of their longer wavelength. With its much larger collecting area, the Webb will be able to image, in infrared, at the same resolution – detail – that Hubble could obtain in the optical part of the spectrum.

    Get ready for a whole new set of mind-blowing images of the universe, this time in the infrared, from Webb!

    6
    After having successfully deployed its solar panels – precisely as it’s supposed to do once it’s in space – the Webb telescope is shown here ready for the final tests on December 17, 2020, at NASA’s Goddard Space Flight Center. Then it will be packed up and transported to French Guyana, to be launched on October 31, 2021, via an Ariane V rocket. Credit: Chris Gunn/NASA.

    The use of deep field surveys is a young science, for two reasons. First, astronomers didn’t have the right instrumentation before Hubble to do them. Second, it’s also because no one initially knew the result of staring into a piece of empty space for a long time. Such a long stare into the unknown would require valuable observation time, and if this long observation didn’t produce any results, it would be considered a waste.

    But in 1995, Robert Williams, then the director of the Space Telescope Science Institute (STScI), which administrates the Hubble telescope, decided to use his “director’s discretionary time” to point the Hubble toward a very small and absolutely empty-looking part of the sky in the direction of the constellation Ursa Major the Great Bear. There were no stars visible from our Milky Way (or extremely few), no nearby galaxies visible in the field, and no visible gas clouds. Hubble collected photons for 10 consecutive days, and the result, the Hubble Deep Field, was a success and a paradigm changer: A patch of sky about as small as the eye of George Washington on an American quarter (25-cent coin) held out at arm’s length, showed a 10 billion-light-years-long tunnel back in time with a plethora of galaxies – around 3,000 of them – at different evolutionary stages along the way. The field of observational cosmology was born.

    This was done again in 1998 with the Hubble telescope pointed to the southern sky (Hubble Deep Field South), and the result was the same. Thus we learned that the universe is uniform over large scales.

    This was done again in 1998 with the Hubble telescope pointed to the southern sky (Hubble Deep Field South), and the result was the same. Thus we learned that the universe is uniform over large scales.

    Next was the installation of a new, powerful camera on Hubble (the Advanced Camera for Surveys) in 2002.

    NASA/ESA/CSA Hubble Advanced Camera for Surveys.

    The incredible Hubble Ultra Deep Field was acquired in 2004, in a similarly small patch of sky near the constellation Orion, about 1/10 of a full moon diameter (2.4 x 3.4 arc minutes, in contrast to the original Hubble Deep Fields north and south, which were 2.6 x 2.6 arc minutes). And so our reach was extended even deeper into space, and even further back in time, showing light from 10 thousand galaxies along a 13-billion-light-years-long tunnel of space. If you’ll remember that the universe is about 13.77 billion years old, you’ll see this is getting us really close to the beginning!

    7
    In 2013, the Planck space telescope released the most detailed map to date of the cosmic microwave background, the relic radiation from the Big Bang. It was the mission’s first all-sky picture of the oldest light in our universe, imprinted on the sky when it was just 380,000 years old. Now a new, independent study agrees with Planck’s results. That’s good news for astronomers trying to pin down the universe’s age and rate of expansion. Credit ESA/ Planck.

    The Hubble Ultra Deep Field was the most sensitive astronomical image ever made at wavelengths of visible (optical) light until 2012, when an even more refined version was released, called the Hubble eXtreme Deep Field, which reached even farther: 13.2 billion years back in time.

    The JADES survey will be observed in two batches, one on the northern sky and one on the southern in two famous fields called GOODS North and South (abbreviated from Great Observatories Origins Deep Survey).

    11
    GOODS North. Credit NASA/ESA Hubble.

    12
    GOODS South. Credit NASA/ESA Hubble.

    Marcia Rieke, a professor of astronomy at the University of Arizona who co-leads the JADES Team with Pierre Ferruit of the European Space Agency (ESA), explained:

    “We chose these fields because they have such a great wealth of supporting information. They’ve been studied at many other wavelengths, so they were the logical ones to do.”

    8
    Look closely. Every single speck of light in this image is a distant galaxy (except for the very few ones with spikes which are foreground stars). This telescopic field of view is part of the GOODS South field. It’s one of the directions in space that’ll be observed in JADES, a new survey that aims to study the very first galaxies to appear in the infancy of the universe. Image via NASA/ESA Hubble Space Telescope/ NASA/ESA/CSA James Webb Space Telescope site.

    The GOODS fields have been observed with several of the most famous telescopes, covering a great wavelength range from infrared through optical to X-ray. They are not fully as deep (the observations don’t reach as far back) as the Ultra Deep Field, but cover a larger area of the sky (4-5 times larger) and are the most data-rich areas of the sky in terms of depth combined with wavelength coverage. By the way, the first deep field, HDF-N, is located in the GOODS north image, and the Ultra deep field/eXtreme (don’t you love these names?) is located in the GOODS south field.

    There are a large number of ambitious science goals for the JADES program pertaining to the composition of the first galaxies, including the first generation of supermassive black holes. How these came about at such an early time is a mystery. As well, the transition of gas from neutral and opaque to transparent and ionized, something astronomers call the epoch of reionization, is not well understood.

    Epoch of Reionization and first stars. Credit: Caltech.

    JADES team member Andrew Bunker, professor of astrophysics at the University of Oxford (UK), who is also part of the ESA team behind the Webb telescope, said:

    “This transition is a fundamental phase change in the nature of the universe. We want to understand what caused it. It could be that it’s the light from very early galaxies and the first burst of star formation … It is kind of one of the Holy Grails, to find the so-called Population III stars that formed from the hydrogen and helium of the Big Bang.

    7
    This is an image from NASA’s Spitzer Space Telescope of a region of sky in the constellation Draco, covering about 50 by 100 million light-years (6 to 12 arcminutes). In this image all the stars, galaxies and artifacts were masked out. The remaining background reveals a glow that is not attributed to galaxies or stars. This might be the glow of the first stars in the universe. This pseudocolor image comes from infrared data at a wavelength of 3.6 microns, below what the human eye can detect. Credit: NASA/JPL-Caltech/A. Kashlinsky (GSFC).

    People have been trying to do this for many decades and results have been inconclusive so far.”

    But, hopefully, not for much longer!

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.orgin 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. “Being an EarthSky editor is like hosting a big global party for cool nature-lovers,” she says.

     
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