About 13 billion years ago, the stars in the Universe’s earliest galaxies sent photons out into space. Some of those photons ended their epic journey on the James Webb Space Telescope’s gold-plated, beryllium mirrors in the last few months. The JWST gathered these primordial photons over several days to create its first “Deep Field” image.Continue reading “Webb Completes its First “Deep Field” With Nine Days of Observing Time. What did it Find?”
A ‘throwaway’ engineering image from the James Webb Space Telescope’s commissioning phase has turned out to be a stunningly deep view of the cosmos. It rivals the deepest of Hubble Deep Field images in revealing previously unseen distant galaxies.Continue reading “A Test Image From Webb Just Happens to be the Deepest Image Ever Taken of the Universe”
Those images showed everyone that what appears to be a tiny, empty part of the sky contains thousands of galaxies, some dating back to the Universe’s early days. Each of those galaxies can have hundreds of billions of stars. These early galaxies formed only a few hundred million years after the Big Bang. The images inspired awe in the human minds that took the time to understand them. And they’re part of history now.
The upcoming Nancy Grace Roman Space Telescope (NGRST) will capture its own version of those historical images but in wide-angle. To whet our appetites for the NGRST’s image, a group of astrophysicists have created a simulation to show us what it’ll look like.Continue reading “Nancy Grace Roman Telescope Will do its Own, Wide-Angle Version of the Hubble Deep Field”
Update: Hubble took its first picture since it went into safe mode on June 13th! More info here.
On Sunday, June 13th, the Hubble Space Telescope gave the astronomical community a fright when its payload computer suddenly stopped working. This prompted the main computer to put the telescope and its scientific instruments into safe mode. What followed was many tense weeks as the operations team for the HST tried to figure out what the source of the problem was and come up with a strategy for turning Hubble back on.
On Friday, July 17th, after more than a month of checking, re-checking, and attempted restarts, the operations team for Hubble identified the root of the problem and restored power to the telescope’s hardware and all of its instruments. Science operations can now resume, and the pioneering space telescope that gave us over thirty years of dedicated astronomy, cosmology, and astrophysics, still has some life in her!Continue reading “Good News! NASA Announces that they have Fixed Hubble!”
Well, just as the Hubble Space Telescope has successors, so do two of its most famous images. And those successors will come from one of Hubble’s successors, NASA’s Roman Space Telescope.Continue reading “The Roman Space Telescope’s Version of the Hubble Deep Field Will Cover a 100x Larger Area of the Sky”
It allowed us to spot auroras on Saturn and planets orbiting distant suns. It permitted astronomers to see galaxies in the early stages of formation, and look back to some of the earliest periods in the Universe. It also measured the distances to Cepheid variable stars more accurately than ever before, which helped astrophysicists constrain how fast the Universe is expanding (the Hubble Constant).
It did all of this and more, which is why no space telescope is as recognized and revered as the Hubble Space Telescope. And while it’s mission is currently scheduled to end in 2021, Hubble is still breaking new ground. Thanks to the efforts of a research team from the Instituto de Astrofísica de Canarias (IAC), Hubble recently obtained the deepest images of the Universe ever taken from space.Continue reading “Astronomers Process Hubble’s Deepest Image to get Even More Data, and Show that Some Galaxies are Twice as big as Previously Believed”
Since its deployment in 1990, the Hubble Space Telescope has given us some of the richest and most detailed images of our Universe. Many of these images were taken while observing a patch of sky located in the Fornax constellation between September 2003 and January 2004. This region, known as the Hubble Ultra Deep Field (HUDF), contains an estimated 10,000 galaxies, all of which existed roughly 13 billion years ago.
Looking to this region of space, multiple teams of astronomers used the MUSE instrument on the ESO’s Very Large Telescope (VLT) to discover 72 previously unseen galaxies. In a series of ten recently released studies, these teams indicate how they measured the distance and properties of 1600 very faint galaxies in the Ultra Deep Field, revealing new information about star formation and the motions of galaxies in the early Universe.
The original HUDF images, which were published in 2004, were a major milestone for astronomy and cosmology. The thousands of galaxies it observed were dated to less than just a billion years after the Big Bang, ranging from 400 to 800 million years of age. This area was subsequently observed many times using the Hubble and other telescopes, which has resulted in the deepest views of the Universe to date.
One such telescope is the European Southern Observatory‘s (ESO) Very Large Telescope, located in the Paranal Observatory in Chile. Intrinsic to the studies of the HUDF was the Multi Unit Spectroscopic Explorer (MUSE), a panoramic integral-field spectrograph operating in the visible wavelength range. It was the data accumulated by this instrument that allowed for 72 new galaxies to be discovered from this tiny area of sky.
The MUSE HUDF Survey team, which was led by Roland Bacon of the Centre de recherche astrophysique de Lyon (CRAL) and the National Center for Scientific Research (CNRS), included members from multiple European observatories, research institutes and universities. Together, they produced ten studies detailing the precise spectroscopic measurements they conducted of 1600 HUDF galaxies.
This was an unprecedented accomplishment, given that this is ten times as many galaxies that have had similar measurements performed on them in the last decade using ground-based telescopes. As Bacon indicated in an ESO press release:
“MUSE can do something that Hubble can’t — it splits up the light from every point in the image into its component colors to create a spectrum. This allows us to measure the distance, colors and other properties of all the galaxies we can see — including some that are invisible to Hubble itself.”
The galaxies detected in this survey were also 100 times fainter than any galaxies studied in previous surveys. Given their age and their very dim and distant nature, the study of these 1600 galaxies is sure to add to any already very richly-observed field. This,in turn, can only deepen our understanding of how galaxies formed and evolved during the past 13 billions years.
The 72 newly-discovered galaxies that the survey observed are known as Lyman-alpha emitters, a class of galaxy that is extremely distant and only detectable in Lyman-alpha light. This form of radiation is emitted by excited hydrogen atoms, and is thought to be the result of ongoing star formation. Our current understanding of star formation cannot fully explain these galaxies, and they were not visible in the original Hubble images.
Thanks to MUSE’s ability to disperse light into its component colors, these galaxies became more apparent. As Jarle Brinchmann – an astronomer at the University of Leiden and the University of Porto’s (CAUP) Institute of Astrophysics and Space Sciences, and the lead author of one of the papers – described the results of the survey:
“MUSE has the unique ability to extract information about some of the earliest galaxies in the Universe — even in a part of the sky that is already very well studied. We learn things about these galaxies that is only possible with spectroscopy, such as chemical content and internal motions — not galaxy by galaxy but all at once for all the galaxies!”
Another major finding of this survey was the systematic detection of luminous hydrogen halos around galaxies in the early Universe. This finding is expected to give astronomers a new and promising way to study how material flowed in and out of early galaxies, which was central to early star formation and galactic evolution. The series of studies produced by Bacon and his colleagues also indicate a range of other possibilities.
These include studying the role faint galaxies played during cosmic reionization, the period that took place between 150 million to billion years after the Big Bang. It was during this period, which followed the “dark ages” (380 thousand to 150 million years ago) that the first stars and quasars formed and sent ionizing radiation throughout the early Universe. And as Roland Bacon explained, the best may yet be to come:
“Remarkably, these data were all taken without the use of MUSE’s recent Adaptive Optics Facility upgrade. The activation of the AOF after a decade of intensive work by ESO’s astronomers and engineers promises yet more revolutionary data in the future.”
Even before Einstein proposed his groundbreaking Theory of General Relativity – which established that space and time are inextricably linked – scientists have understood that probing deeper into the cosmic field is to also probe farther back in time. The farther we are able to see, the more we are able to learn about how the Universe evolved over the course of billions of years.
Further Reading: ESO
It’s perhaps one of the most famous images in astronomy. The Hubble Ultra Deep Field displays nearly 10,000 galaxies across the observable Universe in both visible and near-infrared light. The smallest, reddest galaxies are among the youngest known, existing when the Universe was just 800 million years old.
But now, with the addition of ultraviolet light the renowned image is even better than ever.
“We’ve taken new observations with the Hubble Space Telescope and made a new image of this very famous region of the sky — the Hubble Ultra Deep Field — which gives us one of the most comprehensive pictures of galaxy evolution ever obtained,” said Harry Teplitz from Caltech, in a talk presented at the American Astronomical Society meeting in Boston today.
The image has undoubtedly captured the minds of amateurs and provided astronomers with a wealth of data, from which to study galaxies in their most primitive stages.
But there was a caveat: without ultraviolet light, which tells us about the youngest and hottest stars, there was a significant gap in our understanding of these forming galaxies. Between 5 and 10 billion light-years away from us — corresponding to a time period when most of the stars in the Universe were born — we were left in the dark.
Compare the new image to an older version:
Now, with the addition of ultraviolet data to the Hubble Ultra Deep Field, astronomers can see unobscured regions of star formation throughout this time period. It will help us understand how galaxies grew in size from small collections of very hot stars — now visible across the observable Universe — to the elegant structures we see today.
Here’s a ‘pan and zoom’ video version of the new image:
For more information on the new and improved Ultra Deep Field, check out the HubbleSite.
This new image of the Hubble Ultra Deep Field (HUDF) 2012 campaign reveals a previously unseen population of seven faraway galaxies, which are observed as they appeared in a period 350 million to 600 million years after the Big Bang. Credit: NASA, ESA, R. Ellis (Caltech), and the UDF 2012 Team
Astronomers using NASA’s Hubble Space Telescope have spotted some of the most distant, dim and ancient galaxies ever detected in a new survey. The images, taken with Hubble’s Wide Field Camera 3 (WFC 3) looks further back in time than any previous Hubble observation, providing information about the conditions in the early Universe.
“This is like a scientific version of the story of Genesis,” said astronomer Avi Loeb from Harvard University.
The seven distant galaxies represent a previously unseen population of galaxies that formed more than 13 billion years ago, when the Universe was less than 3 percent of its present age. In these deepest images to date from Hubble, astronomers were able to take a sample of the amount of galaxies at the time. The results show a smooth decline in the number of galaxies with increasing look-back time to about 450 million years after the Big Bang.
The data provides the first reliable census of this uncharted period of cosmic history, according to the scientists. As astronomers look even deeper into the Universe, galaxy numbers appear to drop off smoothly leading them to believe that the “cosmic dawn” was gradual, not a dramatic event.
“Observations of the microwave afterglow from the Big Bang tell us that reionization happened more than about 13 billion years ago,” said Brant Robertson of the University of Arizona in Tucson, a member of the survey team. “Our data confirms that reionization was a drawn-out process occurring over several hundred million years with galaxies slowly building up their stars and chemical elements. There wasn’t a single dramatic moment when galaxies formed; it was a gradual process.”
These galaxies were found as part of an ambitious Hubble survey of an intensively studied patch of sky known as the Ultra Deep Field (UDF), which was originally taken in 2003-2004, focusing in on a small area in the sky in the constellation Fornax. In the new 2012 campaign, called UDF 2012, a team of astronomers led by Richard Ellis of the California Institute of Technology used the WFC3 to peer deeper into space in near-infrared light than any previous Hubble observation. The observations were made over a period of six weeks during August and September 2012, and the first scientific results are now appearing in a series of scientific papers. The UDF 2012 team is publicly releasing these unique data, after preparing them for other research groups to use.
“Hubble is achieving just great science,” said John Grunsfeld, former astronaut and NASA’s associate administrator for science, speaking at a briefing about the new survey. “This is an origins story, where we’re going back to the beginning, back to the first stars that appeared in the Universe. This validates that when we get James Webb Space Telescope online it will have a lot to look at and a lot to do.”
The James Webb Space Telescope is slated to launch in 2018.
Astronomers detected seven galaxies in the time period 400-600 million years after the Big Bang. All extremely distant, they ranged in distance with redshifts from 8.6 to nearly 12.
Astronomers study the distant universe in near-infrared light because the expansion of space stretches ultraviolet and visible light from galaxies into infrared wavelengths, a phenomenon called “redshift.” The more distant a galaxy, the higher its redshift.
Notably, one of the galaxies may be a distance record breaker, observed 380 million years after the birth of our universe in the Big Bang, corresponding to a redshift of 11.9. This is the galaxy UDFj-39546284, which was previously detected and was originally suggested as the most distant object ever found nearly two years ago by Hubble. Later observations put it at a redshift of 10.3, but the newly refined observations put it even more distant.
A timeline of the Universe and our observations of it. Credit: University of Arizona.
Scientists think that the universe began with the Big Bang about 13.7 billion years ago. Hydrogen formed about 400,000 years later but with no stars, spacetime was dark. About 200 million years later, hydrogen clouds collapsed forming the first stars and galaxies; what astronomers call the “cosmic dawn.” Light from these new stars began breaking down hydrogen into protons and electrons during a time period called cosmic reionization. In the present universe, scientists see galaxies growing in mass and size with the synthesis of elements, leading to the formation of complex molecules including the components to create life. Our Sun and solar system formed just over 4 billion years ago.
“The team pushed Hubble to its limits. This is probably the farthest back Hubble can look, according to the study leader, Richard Ellis. “We are pushing Hubble well beyond what it was designed to do.”
The Hubble eXtreme Deep Field (XDF) combines Hubble observations taken over the past decade of a small patch of sky in the constellation of Fornax. With a total of over two million seconds of exposure time, it is the deepest image of the Universe ever made. Credit: credit: NASA, ESA, G. Illingworth, D. Magee, and P. Oesch (University of California, Santa Cruz), R. Bouwens (Leiden University), and the HUDF09 Team
Oh my! The Hubble Space Telescope has just outdone itself, taking the deepest-ever view of the Universe. But the new image really is a compilation of work over the past ten years, as the eXtreme Deep Field, or XDF was assembled by combining ten years of observations, with over 2 million seconds of exposure time, taken of a patch of sky in the center of the original Hubble Ultra Deep Field from 2004. The XDF is a small fraction of the angular diameter of the full Moon.
The new full-color XDF image is even more sensitive than the Hubble Ultra Deep Field image from 2004 and the original Hubble Deep Field image from 1995. The new XDF image contains about 5,500 galaxies, even within its smaller field of view. The faintest galaxies are one ten-billionth the brightness that the unaided human eye can see.
Continue reading “Hubble Goes to the eXtreme in Stunning New Deepest View Ever of the Universe”