Hubble Space Telescope Archives

November 21, 2014December 23, 2015 by Matt Williams

Subaru Telescope Spots Galaxies From The Early Universe

The expansion of the universe over most of its history has been relatively gradual. The notion that a rapid period "inflation" preceded the Big Bang expansion was first put forth 25 years ago. The new WMAP observations favor specific inflation scenarios over other long held ideas. — A team of astronomers have used the Subaru Telescope to look back more than 13 billion years to find 7 early galaxies that appeared quite suddenly within 700 million years of the Big Bang . Credit: NASA/WMAP Science Team

It’s an amazing thing, staring into deep space with the help of a high-powered telescope. In addition to being able to through the vast reaches of space, one is also able to effectively see through time.

Using the Subaru Telescope’s Suprime-Cam, a team of astronomers has done just that. In short, they looked back 13 billion years and discovered 7 early galaxies that appeared quite suddenly within 700 million years of the Big Bang. In so doing, they discovered clues to one of astronomy’s most burning questions: when and how early galaxies formed in our universe.

The team, led by graduate student Akira Konno and Dr. Masami Ouchi (Associate Professor at the University of Tokyo’s ICRR) was looking for a specific kind of galaxy called a Lyman-alpha emitter (LAE), to understand the role such galaxies may have played in an event called “cosmic reionization”.

The current cosmological model states that the universe was born in the Big Bang some 13.8 billion years ago. In its earliest epochs, it was filled with a hot “soup” of charged protons and electrons. As the newborn universe expanded, its temperature decreased uniformly.

Credit: NASA, ESA & A. Felid (STScI)). — *It is estimated that the first stars and galaxies formed 12.8 billion years ago, during a period of “cosmic reionization”. Credit: NASA/ESA/A. Felid (STScI)*

When the universe was 400,000 years old, conditions were cool enough to allow the protons and electrons to bond and form neutral hydrogen atoms. That event is called “recombination” and resulted in a universe filled with a “fog” of these neutral atoms.

Eventually the first stars and galaxies began to form, and their ultraviolet light ionized the hydrogen atoms, and “divided” the neutral hydrogen into protons and electrons again. As this occurred, the “fog” of neutral hydrogen cleared.

Astronomers call this event “cosmic reionization” and think that it ended about 12.8 billion years ago – a billion years after the Big Bang. The timing of this event – when it started and how long it lasted – is one of the big questions in astronomy.

To investigate this cosmic reionization, the Subaru team searched for early LAE galaxies at a distance of 13.1 billion light years. Although Hubble Space Telescope has found more distant LAE galaxies, the discovery of seven such galaxies at 13.1 billion light-years represents a distance milestone for Subaru Telescope.

Color composite images of seven LAEs found in this study as they appeared 13.1 billion years ago. This represents the combination of three filter images from Subaru Telescope. Red objects between two white lines are the LAEs. The LAEs of 13.1 billion years ago have a quite red color due to the effects of cosmic expansion on their component wavelengths of light. Credit: ICRR, University of Tokyo — *Color composite images of seven LAEs found in the study. The red objects between two white lines are the LAEs. Credit: ICRR, University of Tokyo*

Mr. Konno, the graduate student heading the analysis of the data from the Subaru Telescope pointed out the obstacles that Subaru had to overcome to make the observations.”It is quite difficult to find the most distant galaxies due to the faintness of the galaxies.” he said. “So, we developed a special filter to be able to find a lot of faint LAEs. We loaded the filter onto Suprime-Cam and conducted the most distant LAE survey with the integration time of 106 hours.”

That extremely long integration time was one of the longest ever performed at Subaru Telescope. It allowed for unprecedented sensitivity and enabled the team to search for as many of the most distant LAEs as possible.

According to Konno, the team expected to find several tens of LAEs. Instead they only found seven.

“At first we were very disappointed at this small number,” Konno said. “But we realized that this indicates LAEs appeared suddenly about 13 billion years ago. This is an exciting discovery. We can see that the luminosities suddenly brightened during the 700-800 million years after the Big Bang. What would cause this?”

Figure 2: This shows evolution of the Lyman-alpha luminosities of the galaxies. The yellow circle at 1 billion years after the Big Bang is used for normalization. The yellow circles come from previous studies, and the yellow dashed line shows the expected evolutionary trend of the luminosity. The current finding is shown by a red circle, and we can see that the galaxies appear suddenly when the universe was 700 million years old. This indicates that the neutral hydrogen fog was suddenly cleared, allowing the galaxies to shine out, as indicated by the backdrop shown for scale and illustration. Credit: ICRR, University of Tokyo; Hubble Space Telescope/NASA/ESA — *This shows evolution of the Lyman-alpha luminosities of the galaxies. Credit: ICRR, University of Tokyo; Hubble Space Telescope/NASA/ESA*

As the table above illustrates, the luminosities of LAEs changed based on this study. The yellow circle at 1 billion years after the Big Bang is used for normalization. The yellow circles come from previous studies, and the yellow dashed line shows the expected evolutionary trend of the luminosity.

The current finding is shown by a red circle, and we can see that the galaxies appear suddenly when the universe was 700 million years old. This indicates that the neutral hydrogen fog was suddenly cleared, allowing the galaxies to shine out, as indicated by the backdrop shown for scale and illustration.

According to the team’s analysis, one reason that LAEs appeared very quickly is cosmic reionization. LAEs in the epoch of cosmic reionization became darker than the actual luminosity due to the presence of the neutral hydrogen fog.

In the team’s analysis of their observations, they suggest the possibility that the neutral fog filling the universe was cleared about 13.0 billion years ago and LAEs suddenly appeared in sight for the first time.

“However, there are other possibilities to explain why LAEs appeared suddenly,” said Dr. Ouchi, who is the principal investigator of this program. “One is that clumps of neutral hydrogen around LAEs disappeared. Another is that LAEs became intrinsically bright. The reason of the intrinsic brightening is that the Lyman-alpha emission is not efficiently produced by the ionized clouds in a LAE due to the significant escape of ionizing photons from the galaxy. In either case, our discovery is an important key to understanding cosmic reionization and the properties of the LAEs in early universe.”

Dr. Masanori Iye, who is a representative of the Thirty Meter Telescope (TMT) project of Japan, commented on the observations and analysis. “To investigate which possibility is correct, we will observe with HSC (Hyper Suprime-Cam) on Subaru Telescope, which has a field of view 7 times wider than Suprime-Cam, and TMT currently being built on the summit of Mauna Kea in Hawaii in the future. By these observations, we will clarify the mystery of how galaxies were born and cosmic reionization occurred.”

It’s Complicated: Hubble Survey Finds Unexpected Diversity in Dusty Discs Around Nearby Stars

Images captured by the Hubble Telescope of the vast debris systems surrounding nearby stars. Credit: NASA/ESA/ G. Schneider (University of Arizona), and the HST/GO 12228 Team

Using NASA’s Hubble Space Telescope, astronomers have completed the largest and most sensitive visible-light imaging survey of the debris disks surrounding nearby stars. These dusty disks, likely created by collisions between leftover objects from planet formation, were imaged around stars as young as 10 million years old and as mature as more than 1 billion years old.

The research was conducted by astronomers from NASA’s Goddard Space Center with the help of the University of Arizona’s Steward Observatory. The survey was led by Glenn Schneider, the results of which appeared in the Oct. 1, 2014, issue of The Astronomical Journal.

“We find that the systems are not simply flat with uniform surfaces,” Schneider said. “These are actually pretty complicated three-dimensional debris systems, often with embedded smaller structures. Some of the substructures could be signposts of unseen planets.”

In addition to learning much about the debris fields that surround neighboring stars, the study presented an opportunity to learn more about the formation of our own Solar System.

“It’s like looking back in time to see the kinds of destructive events that once routinely happened in our solar system after the planets formed,” said Schneider.

Once thought to be flat disks, the study revealed an unexpected diversity and complexity of dusty debris structures surrounding the observed stars. This strongly suggest they are being gravitationally affected by unseen planets orbiting the star.

Alternatively, these effects could result from the stars’ passing through interstellar space. In addition, the researchers discovered that no two “disks” of material surrounding stars were alike.

A circumstellar disk of debris around a matured stellar system may indicate that Earth-like planets lie within. Credit: NASA/JPL — *A circumstellar disk of debris around a matured stellar system may indicate that Earth-like planets lie within.* *Credit: NASA/JPL*

The astronomers used Hubble’s Space Telescope Imaging Spectrograph to study 10 previously discovered circumstellar debris systems, plus MP Mus, a mature protoplanetary disk that is comparable in age to the youngest of the debris disks.

Irregularities observed in one ring-like system in particular (around HD 181327) resemble the ejection of a huge spray of debris into the outer part of the system from the recent collision of two bodies.

“This spray of material is fairly distant from its host star — roughly twice the distance that Pluto is from the Sun,” said co-investigator Christopher Stark of NASA’s Goddard Space Flight Center, Greenbelt, Maryland. “Catastrophically destroying an object that massive at such a large distance is difficult to explain, and it should be very rare. If we are in fact seeing the recent aftermath of a massive collision, the unseen planetary system may be quite chaotic.”

Another interpretation for the irregularities is that the disk has been mysteriously warped by the star’s passage through interstellar space, directly interacting with unseen interstellar material. “Either way, the answer is exciting,” Schneider said. “Our team is currently analyzing follow-up observations that will help reveal the true cause of the irregularity.”

Over the past few years astronomers have found an incredible diversity in the architecture of exoplanetary systems. For instance, they have found that planets are arranged in orbits that are markedly different than found in our solar system.

A collision between planets could be the reason for the debris field around HD 181327. Credit: NASA/JPL-Caltech — *A collision between two bodies is one explanation for the ring-like debris system around HD 181327. Credit: NASA/JPL-Caltech*

“We are now seeing a similar diversity in the architecture of accompanying debris systems,” Schneider said. “How are the planets affecting the disks, and how are the disks affecting the planets? There is some sort of interdependence between a planet and the accompanying debris that might affect the evolution of these exoplanetary debris systems.”

From this small sample, the most important message to take away is one of diversity, Schneider said. He added that astronomers really need to understand the internal and external influences on these systems – such as stellar winds and interactions with clouds of interstellar material – and how they are influenced by the mass and age of the parent star, and the abundance of heavier elements needed to build planets.

Though astronomers have found nearly 4,000 exoplanet candidates since 1995, mostly by indirect detection methods, only about two dozen light-scattering, circumstellar debris systems have been imaged over that same time period.

That’s because the disks are typically 100,000 times fainter than (and often very close to) their bright parent stars. The majority have been seen because of Hubble’s ability to perform high-contrast imaging, in which the overwhelming light from the star is blocked to reveal the faint disk that surrounds the star.

The new imaging survey also yields insight into how our solar system formed and evolved 4.6 billion years ago. In particular, the suspected planet collision seen in the disk around HD 181327 may be similar to how the Earth-Moon system formed, as well as the Pluto-Charon system over 4 billion years ago. In those cases, collisions between planet-sized bodies cast debris that then coalesced into a companion moon.

Further Reading: The Hubble Site

November 3, 2014December 23, 2015 by Shannon Hall

Hubble Spots the Ghostly Light From Dead Galaxies

Hubble Frontier Fields observing programme, which is using the magnifying power of enormous galaxy clusters to peer deep into the distant Universe. Credit: NASA.

In a patch of sky 3.5 billion light-years away there are hazy elliptical galaxies, colorful spirals, blue arcs and distorted shapes seen clumping together. It’s the result of a vast cosmic collision that took place over the course of 350 million years.

The mess is a treasure trove of information for astronomers, allowing them to piece together the history of a cosmic pile-up of multiple galaxy clusters.

But now astronomers are digging through the nearby darkness. They’re eyeing the remnant stars that were cast adrift in intergalactic space. These stars should emit a faint glow known as intracluster light that — until now — has mostly remained a subject of speculation.

Mireia Montes and Ignacio Trujillo, both from the University of La Laguna, Spain, have used the Hubble Space Telescope to observe the aforementioned cluster, Abel 2744, in exquisite detail. The cluster has already earned the nickname Pandora’s Cluster for its violent past.

The team looked at both visible and near-infrared color images of the cluster, and then split these color images by brightness. This allowed Montes and Trujillo to pinpoint the color of the cluster’s faintest glow and therefore glean the ghost stars’ age, chemical content, and total mass.

Compared to stars within the cluster’s galaxies, the ghost stars emit bluer light and are therefore rich in heavier elements like oxygen, carbon, and nitrogen. So the scattered stars must be second- or third-generation stars enriched by previous supernovae. But they’re still between three and nine billion years younger than the stars within the cluster’s galaxies.

The team estimates that the combined light of about 100 billion outcast stars contributes approximately six percent of the cluster’s brightness.

But how did the stars get thrown from their respective galaxies in the first place? This new forensic evidence suggests that violent collisions tore apart between four and six Milky Way-size galaxies, scattering their stars into intergalactic space.

“The Hubble data revealing the ghost light are important steps forward in understanding the evolution of galaxy clusters,” said Trujillo in a news release. “It is also amazingly beautiful in that we found the telltale glow by utilizing Hubble’s unique capabilities.”

Abell 2744 is only one target in Hubble’s Frontier Fields program, which will map five more galaxy clusters in superb detail.

The results have been published in the Astrophysical Journal and are available online.

October 28, 2014January 15, 2019 by Matt Williams

Just In Time for Halloween: Jupiter Gets a Giant Cyclops Eye!

Jupiter's Great Red Spot and Ganymede's Shadow. Image Credit: NASA/ESA/A. Simon (Goddard Space Flight Center)

Halloween is just around the corner. And in what appears to be an act of cosmic convergence, Hubble captured a spooky image of Jupiter staring back at us with a cyclops eye!

While this is merely a convenient illusion caused by the passage of Ganymede in front of Jupiter – something it does on a regular basis – the timing and appearance are perfect.

Continue reading “Just In Time for Halloween: Jupiter Gets a Giant Cyclops Eye!”

July 31, 2014December 23, 2015 by Shannon Hall

Hubble Spots Farthest Lensing Galaxy Yet

Credit: NASA, ESA, K.-V. Tran (Texas A&M University), and K. Wong (Academia Sinica Institute of Astronomy & Astrophysics)

Sometimes there’s a chance alignment — faraway in the universe, where objects are separated by unimaginable distances measured in billions of light-years — when a galaxy cluster in the foreground intersects light from an even more distant object. The conjunction plays visual tricks, where the galaxy cluster acts like a lens, appearing to magnify and bend the distant light.

The rare cosmic alignment can bring the distant universe into view. Now, astronomers have stumbled upon a surprise: they’ve detected the most distant cosmic magnifying glass yet.

Seen above as it looked 9.6 billion years ago, this monster elliptical galaxy breaks the previous record holder by 200 million light-years. It’s bending, distorting and magnifying the distant spiral galaxy, whose light has taken 10.7 billion years to reach Earth.

“When you look more than 9 billion years ago in the early universe, you don’t expect to find this type of galaxy-galaxy lensing at all,” said lead researcher Kim-Vy Tran from Texas A&M University in a Hubble press release.

“Imagine holding a magnifying glass close to you and then moving it much farther away. When you look through a magnifying glass held at arm’s length, the chances that you will see an enlarged object are high. But if you move the magnifying glass across the room, your chances of seeing the magnifying glass nearly perfectly aligned with another object beyond it diminishes.”

The team was studying star formation in data collected by the W. M. Keck Observatory in Hawai’i, when they came across a strong detection of hot hydrogen gas that appeared to arise form a massive, bright elliptical galaxy. It struck the team as odd. Hot hydrogen is a clear sign of star birth, but it was detected in a galaxy that looked far too old to be forming new stars.

“I was very surprised and worried,” Tran recalled. “I thought we had made a major mistake with our observations.”

So Tran dug through archived Hubble images, which revealed a smeared, blue object next to the larger elliptical. It was the clear signature of a gravitational lens.

“We discovered that light from the lensing galaxy and from the background galaxy were blended in the ground-based data, which was confusing us,” said coauthor Ivelina Momcheva of Yale University. “The Keck spectroscopic data hinted that something interesting was going on here, but only with Hubble’s high-resolution spectroscopy were we able to separate the lensing galaxy from the more distant background galaxy and determine that the two were at different distances. The Hubble data also revealed the telltale look of the system, with the foreground lens in the middle, flanked by a bright arc on one side and a faint smudge on the other — both distorted images of the background galaxy. We needed the combination of imaging and spectroscopy to solve the puzzle.”

By gauging the intensity of the background galaxy’s light, the team was able to measure the giant galaxy’s total mass. All in all it weighs 180 billion times more than our Sun. Although this may seem big, it actually weighs four times less than the Milky Way galaxy.

“There are hundreds of lens galaxies that we know about, but almost all of them are relatively nearby, in cosmic terms,” said lead author Kenneth Wong from the Academia Sinica Institute of Astronomy & Astrophysics. “To find a lens as far away as this one is a very special discovery because we can learn about the dark-matter content of galaxies in the distant past. By comparing our analysis of this lens galaxy to the more nearby lenses, we can start to understand how that dark-matter content has evolved over time.”

Interestingly, the lensing galaxy is underweight in terms of its dark-matter content. In the past, astronomers have assumed that dark matter and normal matter build up equally in a galaxy over time. But this galaxy, suggests this is not the case.

The team’s results appeared in the July 10 issue of The Astrophysical Journal Letters and is available online.

July 26, 2014December 23, 2015 by Ken Kremer

James Webb Space Telescope’s Giant Sunshield Test Unit Unfurled First Time

The sunshield test unit on NASA's James Webb Space Telescope is unfurled for the first time. Credit: NASA

GODDARD SPACE FLIGHT CENTER, MD – The huge Sunshield test unit for NASA’s James Webb Space Telescope (JWST) has been successfully unfurled for the first time in a key milestone ahead of the launch scheduled for October 2018.

Engineers stacked and expanded the tennis-court sized Sunshield test unit last week inside the cleanroom at a Northrop Grumman facility in Redondo Beach, California.

NASA reports that the operation proceeded perfectly the first time during the test of the full-sized unit.

The Sunshield and every other JWST component must unfold perfectly and to precise tolerances in space because it has not been designed for servicing or repairs by astronaut crews voyaging beyond low-Earth orbit into deep space, William Ochs, Associate Director for JWST at NASA Goddard told me in an exclusive interview.

Artist’s concept of the James Webb Space Telescope (JWST) with Sunshield at bottom. Credit: NASA/ESA

The five layered Sunshield is the largest component of the observatory and acts like a parasol.

Its purpose is to protect Webb from the suns heat and passively cool the telescope and its quartet of sensitive science instruments via permanent shade to approximately 45 kelvins, -380 degrees F, -233 C.

The kite-shaped Sunshield provides an effective sun protection factor or SPF of 1,000,000. By comparison suntan lotion for humans has an SPF of 8 to 40.

Two sides of the James Webb Space Telescope (JWST). Credit: NASA

The extreme cold is required for the telescope to function in the infrared (IR) wavelengths and enable it to look back in time further than ever before to detect distant objects.

The shield separates the observatory into a warm sun-facing side and a cold anti-sun side.

Its five thin membrane layers also provides a stable thermal environment to keep the telescopes 18 primary mirror segments properly aligned for Webb’s science investigations.

JWST is the successor to the 24 year old Hubble Space Telescope and will become the most powerful telescope ever sent to space.

The Webb Telescope is a joint international collaborative project between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).

NASA has overall responsibility and Northrop Grumman is the prime contractor for JWST.

Webb will launch folded up inside the payload fairing of an ESA Ariane V ECA rocket from the Guiana Space Center in Kourou, French Guiana.

In launch configuration, the Sunshield will surround the main mirrors and instruments like an umbrella.

During the post launch journey to the L2 observing orbit at the second Sun-Earth Lagrange point nearly a million miles (1.5 million Km) from Earth, the telescopes mirrors and sunshield will begin a rather complex six month long unfolding and calibration process.

The science instruments have been mounted inside the ISIM science module and are currently undergoing critical vacuum chamber testing at NASA Goddard Space Flight Center which provides overall management and systems engineering.

Gold coated flight spare of a JWST primary mirror segment made of beryllium and used for test operations inside the NASA Goddard clean room. Credit: Ken Kremer- kenkremer.com

The mirror segments have arrived at NASA Goddard where I’ve had the opportunity to observe and report on work in progress.

Stay tuned here for Ken’s continuing JWST, MMS, ISS, Curiosity, Opportunity, SpaceX, Orbital Sciences, Boeing, Orion, MAVEN, MOM, Mars and more Earth and Planetary science and human spaceflight news.

Ken Kremer

Sunshield test unit on NASA's James Webb Space Telescope is unfurled for the first time at Northrup Grumman. Credit: NASA — Sunshield test unit on NASA’s James Webb Space Telescope is unfurled for the first time at Northrup Grumman. Credit: NASA

June 19, 2014December 23, 2015 by Shannon Hall

Powerful Starbursts in Dwarf Galaxies Helped Shape the Early Universe, a New Study Suggests

GOODS field containing distant dwarf galaxies forming stars at an incredible rate. Image Credit: ESO

Massive galaxies in the early Universe formed stars at a much faster clip than they do today — creating the equivalent of a thousand new suns per year. This rate reached its peak 3 billion years after the Big Bang, and by 6 billion years, galaxies had created most of their stars.

New observations from the Hubble Space Telescope show that even dwarf galaxies — the small, low mass clusters of several billion stars — produced stars at a rapid rate, playing a bigger role than expected in the early history of the Universe.

Today, we tend to see dwarf galaxies clinging to larger galaxies, or sometimes engulfed within, rather than existing as blazing collections of stars alone. But astronomers have suspected that dwarfs in the early Universe could turn over stars quickly. The trouble is, most images aren’t sharp enough to reveal the faint, faraway galaxies we need to observe.

“We already suspected that dwarf starbursting galaxies would contribute to the early wave of star formation, but this is the first time we’ve been able to measure the effect they actually had,” said lead author Hakim Atek of the École Polytechnique Fédérale de Lausanne (EPFL) in a press release. “They appear to have had a surprisingly significant role to play during the epoch where the Universe formed most of its stars.”

Previous studies of starburst galaxies in the early Universe were biased toward massive galaxies, leaving out the huge number of dwarf galaxies that existed in this era. But the highly sensitive capabilities of Hubble’s Wide Field Camera 3 have now allowed astronomers to peer at low-mass dwarf galaxies in the distant Universe.

This image represents the data that comes from using the NASA/ESA Hubble Space Telescop's highly-sensitive Wide Field Camera 3 in its grism spectroscopy mode. A grism is a combination of a grating and a prism, and it splits up the light from a galaxy into its constituent colours, producing a spectrum. In this image the continuum of each galaxy is shown as a "rainbow". Astronomers can look at a galaxy’s spectrum and identify light emitted by the hydrogen gas in the galaxy. If there are stars being formed in the galaxy then the intense radiation from the newborn stars heats up the hydrogen gas and makes it glow. All of the light from the hydrogen gas is emitted in a small number of very narrow and bright emission lines. For dwarf galaxies in the early Universe the emission lines are much easier to detect than the faint, almost invisible, continuum. Image Credit: NASA and ESA — This image represents the data that comes from using the NASA/ESA Hubble Space Telescope’s highly-sensitive Wide Field Camera 3 in its grism spectroscopy mode. Image Credit: NASA / ESA

Atek and colleagues looked at 1000 galaxies from roughly three billion years to 10 billion years after the Big Bang. They dug through their data, in search of the H-alpha line: a deep-red visible spectral line, which occurs when a hydrogen electron falls from its third to second lowest energy level.

In star forming regions, the surrounding gas is continually ionized by radiation from the newly formed stars. Once the gas is ionized, the nucleus and removed electron can recombine to form a new hydrogen atom with the electron typically in a higher energy state. This electron will then cascade back to the ground state, a process that produces H-alpha emission about half the time.

So the H-alpha line is an effective probe of star formation and the brightness of the H-alpha line (which is much easier to detect than the faint, almost invisible, continuum) is an effective probe of the star formation rate. From this single line, Attek and colleagues found that the rate at which stars are turning on in early dwarfs is surprisingly high.

“These galaxies are forming stars so quickly that they could actually double their entire mass of stars in only 150 million years — this sort of gain in stellar mass would take most normal galaxies 1-3 billion years,” said co-author Jean-Paul Kneib, also of EPFL.

The team doesn’t yet know why these small galaxies are producing such a vast number of stars. In general, bursts of star formation are thought to follow somewhat chaotic events like galactic mergers or the shock of a supernova. But by continuing to study these dwarf galaxies, astronomers hope to shed light on galactic evolution and help paint a consistent picture of events in the early Universe.

The paper has been published today in the Astrophysical Journal and may be viewed here. The latest Hubblecast (below) also covers this exciting result.

June 3, 2014December 23, 2015 by Shannon Hall

The New and Improved Hubble Ultra Deep Field

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

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:

The original Hubble Ultra-Deep Field (Credit NASA, ESA, and S. Beckwith (STScI) and the HUDF Team).

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.

May 19, 2014December 23, 2015 by Elizabeth Howell

Saturn Aurora Sparkles In New Hubble Images

Several images of an aurora on Saturn's north pole taken in April and May 2013 by the Hubble Space Telescope. Credit: NASA/ESA, Acknowledgement: J. Nichols (University of Leicester)

It’s amazing to see what some flashes of light can tell us. New images the Hubble Space Telescope took of Saturn not only reveal auroras dancing in the north pole, but also reveal some interesting things about the giant planet’s magnetic field.

“It appears that when particles from the Sun hit Saturn, the magnetotail collapses and later reconfigures itself, an event that is reflected in the dynamics of its auroras,” the European Space Agency wrote in a description of the image.

“Saturn was caught during a very dynamic light show – some of the bursts of light seen shooting around Saturn’s polar regions traveled more than three times faster than the speed of the gas giant’s roughly 10-hour rotation period.”

And for those readers that remember the music video from Saturn that the Cassini spacecraft took — also of auroras — ESA said this new research complements what the other spacecraft did, too.

The research has been accepted for publication in Geophysical Research Letters.

Source: ESA

April 28, 2014December 23, 2015 by Nancy Atkinson

Celebrate Hubble’s 24th Birthday by Flying Through the Pillars and Peaks of the Monkey Head Nebula

With the Hubble Space Telescope on board, Discovery begins its roll maneuver after liftoff from Kennedy Space Center on April 24, 1990. Credit: NASA.

The Hubble Space Telescope was launched 24 years ago last week, and this newly released video is a birthday present of sorts — to us!

Here you can fly into the Monkey Head Nebula (also known as NGC 2174), and this video showcases both visible and infrared light views of a collection of pillars along one edge of the nebula. The sequence begins with a view of the night sky near the constellation of Gemini and Orion, then zooms through a region of of pillars and peaks of dust.

Then comes a cross-fade transitions between Hubble’s visible and infrared light views, and it also takes you from a two-dimensional image to a three-dimensional sculpted model of the region. The camera then pulls back to reveal the landscape of evaporating peaks of gas and dust surrounded by stars.

The folks at the HubbleSite say that this visualization is intended to be a reasonable interpretation (not scientifically accurate) and that distances within the model are significantly compressed.