Astronomers find unexpected, dust-obscured star formation in distant galaxy

Cosmos by John Hussey

 

Pushing the limits of the largest single-aperture millimeter telescope in the world, and coupling it with gravitational lensing, astronomers report that they have detected a surprising rate of star formation, four times higher than previously detected, in a dust-obscured galaxy behind a Frontier Fields cluster.

Hubble Space Telescope image of the field containing a massive foreground galaxy cluster, MACSJ0717.5+3745. Pope and colleagues’ dusty galaxy is denoted by the red squares which show three images of the same gravitationally lensed background galaxy. A zoom in of each multiple image is shown in the right panels.

Credit: Original image by NASA, European Space Agency and the Hubble Space Telescope Frontier Fields team. Color composite from Wikimedia Commons/Judy Schmidt; annotations and zoom panels added by A. Montana.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Pushing the limits of the largest single-aperture millimeter telescope in the world, and coupling it with gravitational lensing, University of Massachusetts Amherst astronomer Alexandra Pope and colleagues report that they have detected a surprising rate of star formation, four times higher than previously detected, in a dust-obscured galaxy behind a Frontier Fields cluster.

As Pope explains, “This very distant, relatively typical galaxy is known to us, and we knew it was forming stars, but we had no idea what its real star-formation rate was because there is so much dust surrounding it. Previous observations couldn’t reach past that. Finding out that 75 percent of its star formation was obscured by dust is remarkable and intriguing. These observations clearly show that we have more to learn.”

She adds, “Historians want to know how civilizations were built up, and we astronomers want to know where and how the elements in the universe were formed and where everything is made of, came from.” The study is accepted for publication in The Astrophysical Journal.

The new tool that has made such revelations possible is the 50-meter Large Millimeter Telescope (LMT) which has been observing as a 32-meter telescope located on an extinct volcano in central Mexico in “early science mode” since 2013. Operated jointly by UMass Amherst and Mexico’s Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE), it offers astonishing new power to peer into dusty galaxies, the astrophysicist says.

Pope, an expert at analyzing how dust masks star formation, says tracing dust-obscured galaxies at early epochs offers good signposts for understanding how the universe became enriched with metals over time. “We know at the basic level that metals are formed in stars, but the rate of buildup over cosmic time we don’t know,” she points out. “We know what we see today but we don’t know how it came about, and we want to fill in that picture.”

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – The Universe – Birth and Death of Stars

r-mass galaxy showing signs of both low metallicity and high dust content may challenge our picture of dust production in the early universe.”

Before the AzTEC camera on the LMT took observations of this galaxy, astronomers relied on Hubble Space Telescope images to study star formation, Pope says. But most star formation is obscured by dust, so the Hubble images could not make a complete census of the buildup of stars in this galaxy. “Previous millimeter observations have been limited to the most extreme dusty galaxies. With this study, we have detected a surprisingly high rate of dust-obscured star formation in a typical galaxy in the early universe.”

With gravitational lensing, researchers use a foreground mass — another galaxy or a galaxy cluster — as a lens. As light from very distant, background galaxies passes through, it is magnified. “This technique offers a way to see things that are much fainter than your telescope can see,” she notes. As traced in Hubble images, the lensed galaxy they studied in the Frontier Fields cluster showed it forming only about four solar masses of new stars per year, which is a “fairly typical” observation and unsurprising to astronomers today, Pope says. “But then the LMT observations revealed another 15 solar masses per year, which means we had been missing about three-quarters of the star formation going on.”

She adds, “We are not yet at the level of detecting all of the star formation going on, but we are getting better. One of the big goals for us is to push observations at longer wavelengths and to trace these very dusty galaxies at early epochs. We are pushing observations in this direction and the fact that Hubble found only one quarter of the star formation in this distant normal galaxy is a huge motivation for doing a lot more studies like this.”

As early as next year, Pope and her colleague Grant Wilson will install on the LMT a new state-of-the-art imaging system he is building, dubbed TolTEC. It will offer mapping speed 100 times faster than the LMT’s current capability making it the fastest millimeter-wavelength polarimetric camera on Earth for conducting deep surveys of the universe, Wilson says. It should allow astronomers to create a census of star-forming galaxies, and observations that require five years to complete today will be done in a little over one week.

Pope says, “Currently, our census of dust-obscured star formation activity in galaxies is severely incomplete, especially in the distant universe. With TolTEC on the LMT, we will be able to make a complete census of dust-obscured star formation activity in galaxies over 13 billion years of cosmic time.

 

Story Source:

Materials provided by University of Massachusetts at Amherst.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2017/03/170323125453.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Milky Way-like galaxies in early universe embedded in ‘super halos’

Cosmos by John Hussey

 

Astronomers have directly observed a pair of Milky Way-like galaxies seen when the universe was only eight percent of its current age. These progenitors of today’s giant spiral galaxies are surrounded by ‘super halos’ of hydrogen gas that extend many tens-of-thousands of light-years beyond their dusty, star-filled disks.

Artist impression of a progenitor of Milky Way-like galaxy in the early universe with a background quasar shinning through a ‘super halo’ of hydrogen gas surrounding the galaxy. New ALMA observations of two such galaxies reveal that these vast halos extend well beyond the galaxies’ dusty, star-forming disks. The galaxies were initially found by the absorption of background quasar light passing through the galaxies. ALMA was able to image the ionized carbon in the galaxies’ disks, revealing crucial details about their structures.

Credit: A. Angelich (NRAO/AUI/NSF)

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

By harnessing the extreme sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have directly observed a pair of Milky Way-like galaxies seen when the universe was only eight percent of its current age. These progenitors of today’s giant spiral galaxies are surrounded by “super halos” of hydrogen gas that extend many tens-of-thousands of light-years beyond their dusty, star-filled disks.

Astronomers initially detected these galaxies by studying the intense light from even-more-distant quasars. As this light travels through an intervening galaxy on its way to Earth, it can pick up the unique spectral signature from the galaxy’s gas. This technique, however, normally prevents astronomers from seeing the actual light emitted by the galaxy, which is overwhelmed by the much brighter emission from the background quasar.

“Imagine a tiny firefly next to a high-power search light. That’s what astronomers are up against when it comes to observing these youthful versions of our home galaxy,” said Marcel Neeleman a postdoctoral fellow at the University of California, Santa Cruz, and lead author on a paper appearing in the journal Science. “We can now see the galaxies themselves, which gives us an amazing opportunity to learn about the earliest history of our own galaxy and others like it.”

With ALMA, the astronomers were finally able to observe the natural millimeter-wavelength “glow” emitted by ionized carbon in the dense and dusty star-forming regions of the galaxies. This carbon signature, however, is considerably offset from the gas first detected by quasar absorption. This extreme separation indicates that the galaxies’ gas content extends well beyond their star-filled disks, suggesting that each galaxy is embedded in a monstrous halo of hydrogen gas.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Black Holes – Milky Way’s Super Massive Black Hole is having dinner

“We had expected we would see faint emissions right on top of the quasar, and instead we saw strong bright carbon emission from the galaxies at large separations from their background quasars,” said J. Xavier Prochaska, professor of astronomy and astrophysics at UC Santa Cruz and coauthor of the paper. The separation from the quasar to the observed galaxy is about 137,000 light-years for one galaxy and about 59,000 light-years for the other.

According to the researchers, the neutral hydrogen gas revealed by its absorption of quasar light is most likely part of a large halo or perhaps an extended disk of gas around the galaxy. “It’s not where the star formation is, and to see so much gas that far from the star-forming region means there is a large amount of neutral hydrogen around the galaxy,” Neeleman said.

The new ALMA data show that these young galaxies are already rotating, which is one of the hallmarks of the massive spiral galaxies we see in the universe today. The ALMA observations further reveal that both galaxies are forming stars at moderately high rates: more than 100 solar masses per year in one galaxy and about 25 solar masses per year in the other.

“These galaxies appear to be massive, dusty, and rapidly star-forming systems, with large, extended layers of gas,” Prochaska said.

“ALMA has solved a decades-old question on galaxy formation,” said Chris Carilli, an astronomer with the National Radio Astronomy Observatory in Socorro, N.M., and co-author on the paper. “We now know that at least some very early galaxies have halos that are much more extended that previously considered, which may represent the future material for galaxy growth.”

The galaxies, which are officially designated ALMA J081740.86+135138.2 and ALMA J120110.26+211756.2, are each about 12 billion light-years from Earth. The background quasars are each roughly 12.5 billion light-years from Earth.

 

Story Source:

Materials provided by National Radio Astronomy Observatory.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2017/03/170323141405.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Shadow of a gas cloud detected in an ancient proto-supercluster

Cosmos by John Hussey

 

The Suprime-Cam on the Subaru Telescope has been used to create the most-extensive map of neutral hydrogen gas in the early universe. This cloud appears widely spread out across 160 million light-years in and around a structure called the proto-supercluster. It is the largest structure in the distant universe, and existed some 11.5 billion years ago. Such a huge gas cloud is extremely valuable for studying large-scale structure formation and the evolution of galaxies from gas in the early universe, and merits further investigation.

The distribution of galaxies in the proto-supercluster region 11.5 billion years ago (top left), and the Subaru Telescope Suprime-Cam image used in this work (right, larger image). Neutral hydrogen gas distribution is superposed on the Subaru image. The red color indicates denser regions of the neutral hydrogen gas. Cyan squares correspond to member galaxies in the proto-supercluster, while objects without cyan squares are foreground galaxies and stars. The distribution of neutral hydrogen gas does not align perfectly with the galaxies.

Credit: Osaka Sangyo University / NAOJ

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

A team led by researchers from Osaka Sangyo University, with members from Tohoku University, Japan Aerospace Exploration Agency (JAXA) and others, has used the Suprime-Cam on the Subaru Telescope to create the most-extensive map of neutral hydrogen gas in the early universe. This cloud appears widely spread out across 160 million light-years in and around a structure called the proto-supercluster. It is the largest structure in the distant universe, and existed some 11.5 billion years ago. Such a huge gas cloud is extremely valuable for studying large-scale structure formation and the evolution of galaxies from gas in the early universe, and merits further investigation.

“We are surprised because the dense gas structure is extended much more than expected in the proto-supercluster,” said Dr. Mawatari. “Wider field observations with narrow-band filters are needed to grasp full picture of this largest structure in the young Universe. This is exactly the type of strong research that can be done with Hyper Suprime-Cam (HSC) recently mounted at the Subaru Telescope. We intend to study the gas — galaxy relation in various proto-superclusters using the HSC.”

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Universe – Our Place In The Milky Way

Understanding Matter Distribution in the Universe

Stars assembled to form galaxies, and galaxies are clustered to form larger structures such as clusters or superclusters. Matter in the current universe is structured in a hierarchical manner on scales of ~ 100 million light-years. However, we cannot observe inhomogeneous structure in any direction or distance over scales larger than that. One important issue in modern astronomy is to clarify how perfectly the large-scale uniformity and homogeneity in matter distribution is maintained. In addition, astronomers seek to investigate the properties of the seeds of large-scale structures (i.e., the initial matter fluctuations) that existed at the beginning of the universe. Thus, it is important to observe huge structures at various epochs (which translates to distances). The study of gaseous matter as well as galaxies is needed for an accurate and comprehensive understanding. This is because local superclusters are known to be rich in gas. Furthermore, it is clear that there are many newborn galaxies in ancient (or distant) clusters. A detailed comparison between the spatial distributions of galaxies and gas during the early epochs of the universe is very important to understand process of galaxy formation from the dim (low light-emitting) clumps of gas in the early universe.

In order to investigate early, dim gas clouds, astronomers take advantage of the fact that light from bright distant objects gets dimmed by foreground gas (giving an effect like a “shadow picture”). Since neutral hydrogen in the gas cloud absorbs and dims light from background objects at a certain wavelength, we can see characteristic absorption feature in the spectrum of the background object. In many previous observations, researchers used quasars (which are very bright and distant) as background light sources. Because bright quasars are very rare, opportunities for such observations are limited. This allows astronomers to get information about the gas that lies only along the line of sight between a single QSO and Earth in a wide survey area. It has long been the goal to obtain “multi-dimensional” information of gas (e.g., spatially resolve the gas clouds) rather than the “one-dimensional” view currently available. This requires a new approach.

 

Expanding the View

To widen their view of these objects in the early universe, Dr. Ken Mawatari at Osaka Sangyo University and his colleagues recently developed a scheme to analyze the spatial distribution of the neutral hydrogen gas using imaging data of galaxies of the distant epoch. There are two major advantages to this approach. First, instead of rare quasars, the team uses numerous normal galaxies as background light sources to investigate gas distribution at various places in the search area. Second, they use imaging data taken with the narrow-band filter on Suprime-cam. It is fine-tuned so that light with certain wavelengths can be transmitted, to capture evidence of absorption by the neutral hydrogen gas (the shadow picture effect). Compared with the traditional scheme of observations based on spectroscopy of quasars, this new method enables Mawatari and his collaborators to obtain wide-area gas distribution information relatively quickly.

The researchers applied their scheme to the Subaru Telescope Suprime-Cam imaging data taken in their previous large survey of galaxies. The fields investigated in this work include the SSA22 field, an ancestor of a supercluster of galaxies (proto-supercluster), where young galaxies are formed actively, in the universe 11.5 billion years ago in the early universe.

 

New Maps of Neutral Hydrogen Distribution

The researchers’ work resulted in very wide-area maps of the neutral hydrogen gas in the three fields studied. It appears that the neutral hydrogen gas absorption is significantly strong over the entire SSA22 proto-supercluster field compared with those in the normal fields (SXDS and GOODS-N). It is clearly confirmed that the proto-supercluster environment is rich in neutral hydrogen gas, which is the major building block of galaxies.

The team’s work also revealed that gas distribution in the proto-supercluster region does not align with the galaxies’ distribution perfectly. While the proto-supercluster is rich in both galaxies and gas, there is no local-scale dependency of gas amount correlated with the density of galaxies inside the proto-supercluster. This result may mean that the neutral hydrogen gas not only is associated with the individual galaxies but also spreads out diffusely across intergalactic space only within the proto-supercluster. Since the neutral hydrogen gas excess in the SSA22 field is detected over the entire searched area, this overdense gas structure is actually extended more than 160 million light-years. In the traditional view of structure formation, matter density fluctuation is thought to be smaller and large-scale high-density structure was rarer in the early universe. The discovery that a gas structure that extends across more than 160 million light-years (which is roughly same as present-day superclusters in scale) already existed in the universe 11.5 billion years ago is a surprising result of this study.

By investigating spatial distribution of the neutral hydrogen gas in a very large area, the researchers have provided a new window on the relation between gas and galaxies in the young universe. The SSA22 huge gas structure revealed by this work is considered a key object to test the standard theory of structure formation, and so further investigation is anticipated.

This research will be published in the journal of the British Royal Astronomical Society (Monthly Notices of the Royal Astronomical Society, publisher Oxford University Press) in its June, 2017 issue of the printed version.

 

Story Source:

Materials provided by National Astronomical Observatory of Japan.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2017/03/170329103711.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Explaining the accelerating expansion of the universe without dark energy

Cosmos by John Hussey

 

Enigmatic dark energy, thought to make up 68% of the universe, may not exist at all, according to a Hungarian-American team. The researchers believe that standard models of the universe fail to take account of its changing structure, but that once this is done the need for dark energy disappears.

This is a frame from an animation that shows the expansion of the universe in the standard ‘Lambda Cold Dark Matter’ cosmology, which includes dark energy (top left panel red), the new Avera model, that considers the structure of the universe and eliminates the need for dark energy (top middle panel, blue), and the Einstein-de Sitter cosmology, the original model without dark energy (top right, green). The panel at the bottom shows the increase of the ‘scale factor’ (an indication of the size) as a function of time, where 1Gya is 1 billion years. The growth of structure can also be seen in the top panels. One dot roughly represents an entire galaxy cluster. Units of scale are in Megaparsecs (Mpc), where 1 Mpc is around 3 million million million km.

Credit: István Csabai et al.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Enigmatic dark energy, thought to make up 68% of the universe, may not exist at all, according to a Hungarian-American team. The researchers believe that standard models of the universe fail to take account of its changing structure, but that once this is done the need for dark energy disappears. The team publish their results in a paper in Monthly Notices of the Royal Astronomical Society.

Our universe was formed in the Big Bang, 13.8 billion years ago, and has been expanding ever since. The key piece of evidence for this expansion is Hubble’s law, based on observations of galaxies, which states that on average, the speed with which a galaxy moves away from us is proportional to its distance.

Astronomers measure this velocity of recession by looking at lines in the spectrum of a galaxy, which shift more towards red the faster the galaxy is moving away. From the 1920s, mapping the velocities of galaxies led scientists to conclude that the whole universe is expanding, and that it began life as a vanishingly small point.

In the second half of the twentieth century, astronomers found evidence for unseen ‘dark’ matter by observing that something extra was needed to explain the motion of stars within galaxies. Dark matter is now thought to make up 27% of the content of universe (in contrast ‘ordinary’ matter amounts to only 5%).

Observations of the explosions of white dwarf stars in binary systems, so-called Type Ia supernovae, in the 1990s then led scientists to the conclusion that a third component, dark energy, made up 68% of the cosmos, and is responsible for driving an acceleration in the expansion of the universe.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

View Sample Video – Cosmology – Universe – Dark Matter and Dark Energy

In the new work, the researchers, led by PhD student Gábor Rácz of Eötvös Loránd University in Hungary, question the existence of dark energy and suggest an alternative explanation. They argue that conventional models of cosmology (the study of the origin and evolution of the universe), rely on approximations that ignore its structure, and where matter is assumed to have a uniform density.

“Einstein’s equations of general relativity that describe the expansion of the universe are so complex mathematically that for a hundred years no solutions accounting for the effect of cosmic structures have been found. We know from very precise supernova observations that the universe is accelerating, but at the same time we rely on coarse approximations to Einstein’s equations which may introduce serious side-effects, such as the need for dark energy, in the models designed to fit the observational data.” explains Dr László Dobos, co-author of the paper, also at Eötvös Loránd University.

In practice, normal and dark matter appear to fill the universe with a foam-like structure, where galaxies are located on the thin walls between bubbles, and are grouped into superclusters. The insides of the bubbles are in contrast almost empty of both kinds of matter.

Using a computer simulation to model the effect of gravity on the distribution of millions of particles of dark matter, the scientists reconstructed the evolution of the universe, including the early clumping of matter, and the formation of large scale structure.

Unlike conventional simulations with a smoothly expanding universe, taking the structure into account led to a model where different regions of the cosmos expand at different rate. The average expansion rate though is consistent with present observations, which suggest an overall acceleration.

Dr Dobos adds: “The theory of general relativity is fundamental in understanding the way the universe evolves. We do not question its validity; we question the validity of the approximate solutions. Our findings rely on a mathematical conjecture which permits the differential expansion of space, consistent with general relativity, and they show how the formation of complex structures of matter affects the expansion. These issues were previously swept under the rug but taking them into account can explain the acceleration without the need for dark energy.”

If this finding is upheld, it could have a significant impact on models of the universe and the direction of research in physics. For the past 20 years, astronomers and theoretical physicists have speculated on the nature of dark energy, but it remains an unsolved mystery. With the new model, the team expect at the very least to start a lively debate.

 

Animation: https://www.youtube.com/watch?v=VF0Lg7CfCYA

 

Story Source:

Materials provided by Royal Astronomical Society.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2017/03/170330115254.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Satellite galaxies at edge of Milky Way coexist with dark matter

Cosmos by John Hussey

 

New research rules out a challenge to the accepted standard model of the universe and theory of how galaxies form by shedding new light on a problematic structure.

The Large Magelanic Cloud is a well-known satellite or dwarf galaxy that closely orbits the Milky Way and is visible in Earth’s southern hemisphere. RIT researchers make the case for the existence of “missing” satellite galaxies that are cloaked in dark matter and cannot be directly observed.

Credit: ESA/NASA/Hubble

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Research conducted by scientists at Rochester Institute of Technology rules out a challenge to the accepted standard model of the universe and theory of how galaxies form by shedding new light on a problematic structure.

The vast polar structure — a plane of satellite galaxies at the poles of the Milky Way — is at the center of a tug-of-war between scientists who disagree about the existence of mysterious dark matter, the invisible substance that, according to some scientists, comprises 85 percent of the mass of the universe.

A paper accepted for publication in the Monthly Notices for the Royal Astronomical Society bolsters the standard cosmological model, or the Cold Dark Matter paradigm, by showing that the vast polar structure formed well after the Milky Way and is an unstable structure.

The study, “Is the Vast Polar Structure of Dwarf Galaxies a Serious Problem for CDM?” was co-authored by Andrew Lipnicky, a Ph.D. candidate in RIT’s astrophysical sciences and technology program, and Sukanya Chakrabarti, assistant professor in RIT’s School of Physics and Astronomy, whose grant from the National Science Foundation supported the research.

Lipnicky and Chakrabarti analyze the distribution of the classical Milky Way dwarf galaxies that form the vast polar structure and compares it to simulations of the “missing” or subhalo dwarf galaxies thought to be cloaked in dark matter.

Using motion measurements, the authors traced the orbits of the classical Milky Way satellites backward in time. Their simulations showed the vast polar structure breaking up and dispersing, indicating that the plane is not as old as originally thought and formed later in the evolution of the galaxy. This means that the vast polar structure of satellite galaxies may be a transient feature, Chakrabarti noted.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Universe – Dark Matter and Dark Energy

“If the planar structure lasted for a long time, it would be a different story,” Chakrabarti said. “The fact that it disperses so quickly indicates that the structure is not dynamically stable. There is really no inconsistency between the planar structure of dwarf galaxies and the current cosmological paradigm.”

The authors removed the classical Milky Way satellites Leo I and Leo II from the study when orbital analyses determined that the dwarf galaxies were not part of the original vast polar structure but later additions likely snatched from the Milky Way. A comparison excluding Leo I and II reveals a similar plane shared by classical galaxies and their cloaked counterparts.

“We tried many different combinations of the dwarf galaxies, including distributions of dwarfs that share similar orbits, but in the end found that the plane always dispersed very quickly,” Lipnicky said.

Opposing scientific thought rejects the existence of dark matter. This camp calls into question the standard cosmological paradigm that accepts both a vast polar structure of satellite galaxies and a hidden plane of dark-matter cloaked galaxies. Lipnicky and Chakrabarti’s study supports the co-existence of these structures and refutes the challenge to the accepted standard model of the universe.

 

Story Source:

Materials provided by Rochester Institute of Technology. Original written by Susan Gawlowicz.

https://www.sciencedaily.com/releases/2017/03/170330164959.htm

 

Cosmos by John Hussey

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Long Ago and Far Away, an Average Galaxy: ‘Typical’ Galaxy Helps Astronomers Study Epoch of Reionization

Cosmos by John Hussey

 

Using a giant galaxy cluster as a cosmic-scale lens, astronomers have discovered a galaxy from the early universe that they think is ‘typical’ of its time. This could help astronomers better understand the Epoch of Reionization when the first galaxies appeared.

Astronomers used the gravity of a massive galaxy cluster as a lens to spot an incredibly distant galaxy, about 13.1 billion years in the past. They used the Hubble Space Telescope to find the galaxy and confirmed its age and distance with instruments at the Keck Observatory in Hawaii.

Credit: NASA/Keck/Austin Hoag/Marusa Bradac

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Astronomers led by a graduate student at the University of California, Davis have discovered one of the most distant galaxies in the universe, and it’s nothing out of the ordinary.

“Other most distant objects are extremely bright and probably rare compared to other galaxies,” said Austin Hoag, a UC Davis graduate student in physics who is lead author on the paper, published April 10 in Nature Astronomy. “We think this is much more representative of galaxies of the time.”

These ultradistant galaxies, seen as they were close to the beginning of the universe, are interesting to Hoag, UC Davis physics professor Marusa Bradac and collaborators in the U.S., Australia and Europe because they fall within the “Epoch of Reionization,” a period about a billion years after the Big Bang when the universe became transparent.

After the Big Bang, the universe was a cloud of cold atomic hydrogen, which blocks light. The first stars and galaxies condensed out of the cloud and started to emit light and ionizing radiation. This radiation melted away the atomic hydrogen like a hot sun clearing fog, and the first galaxies spread their light through the universe.

Much remains lost in the fog of reionization.

“We have a before and an after, but not exactly a when,” Hoag said. There are also questions about what radiating objects drove reionization: Was it mostly young galaxies, or did objects such as black holes and gamma ray bursts contribute as well?

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Universe – Milky Way Galaxy Formation – Simulation

Galaxy Cluster is a Giant Lens in the Sky

The new object, named MACS1423-z7p64, is at a redshift of 7.6, putting it about 13.1 billion years in the past (The farther away an object is, the farther its light is shifted into the red end of the spectrum, due to the expansion of the universe). To find such faint, distant objects, the astronomers took advantage of a giant lens in the sky.

As light passes by a massive object such as a galaxy cluster, its path gets bent by gravity, just as light gets bent passing through a lens. When the object is big enough, it can act as a lens that magnifies the image of objects behind it.

Hoag and colleagues are surveying the sky around massive galaxy clusters that are the right size and distance away to focus light from very distant galaxies. While it is similar to millions of other galaxies of its time, z7p64 just happened to fall into the “sweet spot” behind a giant galaxy cluster that magnified its brightness ten-fold and made it visible to the team, using the Hubble Space Telescope. They were then able to confirm its distance by analyzing its spectrum with the Keck Observatory telescopes in Hawaii.

The team plans to continue their survey of candidate galaxies with the Hubble and Keck telescopes. The upcoming launch of the James Webb Space Telescope, set for 2018, opens up new possibilities, Hoag said. The team is currently planning observations for the Webb telescope, which is bigger than Hubble and will allow astronomers to look at even more distant parts of the Universe.

“We will truly witness the birth of the first galaxies which will allow us to answer the longstanding question, of where did we come from,” Bradac said.

 

Story Source:

Materials provided by University of California – Davis. Original written by Andy Fell.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2017/04/170410124028.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Dark Inflation Opens Up a Gravitational Window Onto the First Moments After the Big Bang

Cosmos by John Hussey

 

Dark matter and dark energy may have driven inflation, the exponential expansion of the Universe moments after the Big Bang. A new cosmological model proposed by physicists, which takes dark inflation into account, is the first to outline a precise chronology of the main events during the early history of our Universe. The model makes a spectacular prediction: that it should be possible to detect gravitational waves that were formed just fractions of a second after the creation of spacetime.

A comparison of the current inflation model of the evolution of the Universe to the dark inflation model recently proposed by scientists from the Faculty of Physics at the University of Warsaw. (Source: UW Physics)

Credit: UW Physics

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Dark matter and dark energy may have driven inflation, the exponential expansion of the Universe moments after the Big Bang. A new cosmological model proposed by physicists at the University of Warsaw, which takes dark inflation into account, is the first to outline a precise chronology of the main events during the early history of our Universe. The model makes a spectacular prediction: that it should be possible to detect gravitational waves that were formed just fractions of a second after the creation of spacetime.

What do we know about the evolution of Universe immediately after the Big Bang? In spite of extensive research carried out over decades, current cosmological models still do not outline a precise chronology of events. Researchers at the Faculty of Physics at the University of Warsaw (UW Physics) have developed a new model in which the exponential expansion of dark matter and dark energy plays a key role. The dark inflation model organises the thermal history of the Universe in chronological order and predicts that we should soon be able to detect primordial gravitational waves formed immediately after the Big Bang.

The earliest structure of the Universe we can study today is cosmic microwave background (CMB) radiation. This electromagnetic relic dates back to around 380,000 years after the Big Bang and is surprisingly homogenous, even in regions which are so far apart that light couldn’t have covered the distance between them in the time available. In 1979, Alan Guth proposed inflation as a simple explanation for this uniformity: the current vast distances between the homogenous regions are so great because at one time there was an extremely rapid expansion of spacetime, enlarging a billion billion billion times over in just fractions of a second. This is said to have been driven by a hypothetical inflation field and particles known as inflatons.

“The fundamental problem with inflation is that we don’t really know when exactly it occurred and at what energy levels. The range of energies at which inflation could have occurred is vast, stretching over 70 orders of magnitude,” explains Prof. Zygmunt Lalak (UW Physics). He adds, “Inflation is described as a period of supercooled expansion. However, for cosmological models to be consistent, following inflation the Universe should have undergone reheating to a very high temperature, and we have no idea how or when this might have occurred. Just like with inflation itself, we are dealing with energies across a range of 70 orders of magnitude. As a result, the thermal history of the Universe is yet to be described.”

Measurements of CMB radiation using the Planck satellite have been used to estimate the composition of the contemporary Universe. It turns out that dark energy comprises as much as 69% of all extant energy/matter, with dark matter comprising 26% and ordinary matter just 5%. Dark matter and ordinary matter don’t interact at all, or their interactions are so weak we are only just starting to notice dark matter’s gravitational impact on the movement of stars in galaxies and galaxies in clusters. Dark energy should be a factor responsible for the accelerated expansion of the Universe.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Universe – Inflation theory

“Our inflation model is significantly different from those proposed in the past. We started with the assumption that since today dark matter and dark energy comprise up to 95% of the Universe’s structure, then both factors must have also been extremely important immediately after the Big Bang. This is why we describe the dark sector of the Universe as responsible for the inflation process,” explains Dr. Michal Artymowski (UW Physics), main author of the paper published in the Journal of Cosmology and Astroparticle Physics.

In the model proposed by the theoretical physicists from the University of Warsaw, inflation is driven by a scalar field. The properties of the field mean that inflation isn’t permanent and it must come to an end: at some point the rate of expansion of the Universe will start slowing down instead of accelerating. At the point of this shift, new relativistic particles are formed, behaving in the same way as radiation. Some of these particles are described by the Standard Model, while others may correspond to particles predicted by theories beyond the Standard Model, such as supersymmetry.

“In our models, the new particles are the result of gravitation, which is a very weak force. The process of formation of particles is ineffective, and at the end of inflation inflatons continue to dominate the Universe,” says Olga Czerwinska, PhD student at UW Physics.

In order to recreate the observed dominance of radiation in the Universe, inflatons should lose energy rapidly. The researchers propose two physical mechanisms which could be responsible for the process. They reveal that the new model predicts the course of events of the Universe’s thermal history with a far greater accuracy than previously.

The model’s predictions concerning primordial gravitational waves are especially interesting. Gravitational waves are vibrations of spacetime itself, and they have already been detected several times. In each case their source has been the merger of a pair of black holes or neutron stars. Current cosmological models predict that gravitational waves should also appear as a result of inflation. However, all the evidence suggested that vibrations of spacetime caused by inflation would be so weak by now that no existing or future detectors would have been able to register them. These predications were revised when physicists from the University of Warsaw took into account the effects of the dark sector of the Universe.

“Gravitational waves lose energy as radiation. However, inflatons must lose it significantly faster. If inflation involved the dark sector, the input of gravitational waves increased proportionally. This means that traces of the primordial gravitational waves are not as weak as we originally thought!” adds Dr. Artymowski.

The estimates made by the Warsaw physicist are optimistic. Data suggests that primordial gravitational waves could be detected by observatories currently at the design stage or under construction, such as the Deci-Hertz Interferometer Gravitational Wave Observatory (DECIGO), Laser Interferometer Space Antenna (LISA), European Pulsar Timing Array (EPTA) and Square Kilometre Array (SKA). The first events could be detected in the coming decade. For cosmologists this would be an unprecedented discovery, paving the way for research into gravitational events which took place immediately after the Big Bang — a period hitherto impossible to study.

The dark inflation model has another fascinating aspect: it is highly dependent on gravitational theory. By comparing the model’s predictions with data collected by gravitational observatories, cosmologists should be able to provide new verifications of Einstein’s general theory of relativity. What happens if they find discrepancies? It would mean that observational data provides the first information on the properties of real gravity.

 

Story Source:

Materials provided by Faculty of Physics University of Warsaw.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2018/06/180607100920.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

A Dozen New Moons of Jupiter Discovered, Including One ‘Oddball’

Cosmos by John Hussey

 

This brings Jupiter’s total number of known moons to a whopping 79 — the most of any planet in our solar system

Twelve new moons orbiting Jupiter have been found — 11 ‘normal’ outer moons, and one that they’re calling an ‘oddball.’ Astronomers first spotted the moons in the spring of 2017 while they were looking for very distant solar system objects as part of the hunt for a possible massive planet far beyond Pluto.

Various groupings of Jovian moons with the newly discovered ones shown in bold. The ‘oddball,’ called Valetudo after the Roman god Jupiter’s great-granddaughter, has a prograde orbit that crosses the retrograde orbits.

Credit: By Roberto Molar-Candanosa, courtesy of Carnegie Institution for Science.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Twelve new moons orbiting Jupiter have been found — 11 “normal” outer moons, and one that they’re calling an “oddball.” This brings Jupiter’s total number of known moons to a whopping 79 — the most of any planet in our Solar System.

A team led by Carnegie’s Scott S. Sheppard first spotted the moons in the spring of 2017 while they were looking for very distant Solar System objects as part of the hunt for a possible massive planet far beyond Pluto.

In 2014, this same team found the object with the most-distant known orbit in our Solar System and was the first to realize that an unknown massive planet at the fringes of our Solar System, far beyond Pluto, could explain the similarity of the orbits of several small extremely distant objects. This putative planet is now sometimes popularly called Planet X or Planet Nine. University of Hawaii’s Dave Tholen and Northern Arizona University’s Chad Trujillo are also part of the planet search team.

“Jupiter just happened to be in the sky near the search fields where we were looking for extremely distant Solar System objects, so we were serendipitously able to look for new moons around Jupiter while at the same time looking for planets at the fringes of our Solar System,” said Sheppard.

Gareth Williams at the International Astronomical Union’s Minor Planet Center used the team’s observations to calculate orbits for the newly found moons.

“It takes several observations to confirm an object actually orbits around Jupiter,” Williams said. “So, the whole process took a year.”

Nine of the new moons are part of a distant outer swarm of moons that orbit it in the retrograde, or opposite direction of Jupiter’s spin rotation. These distant retrograde moons are grouped into at least three distinct orbital groupings and are thought to be the remnants of three once-larger parent bodies that broke apart during collisions with asteroids, comets, or other moons. The newly discovered retrograde moons take about two years to orbit Jupiter.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Planets – Jupiter – The Giant Planet

Two of the new discoveries are part of a closer, inner group of moons that orbit in the prograde, or same direction as the planet’s rotation. These inner prograde moons all have similar orbital distances and angles of inclinations around Jupiter and so are thought to also be fragments of a larger moon that was broken apart. These two newly discovered moons take a little less than a year to travel around Jupiter.

“Our other discovery is a real oddball and has an orbit like no other known Jovian moon,” Sheppard explained. “It’s also likely Jupiter’s smallest known moon, being less than one kilometer in diameter.”

This new “oddball” moon is more distant and more inclined than the prograde group of moons and takes about one and a half years to orbit Jupiter. So, unlike the closer-in prograde group of moons, this new oddball prograde moon has an orbit that crosses the outer retrograde moons.

As a result, head-on collisions are much more likely to occur between the “oddball” prograde and the retrograde moons, which are moving in opposite directions.

“This is an unstable situation,” said Sheppard. “Head-on collisions would quickly break apart and grind the objects down to dust.”

It’s possible the various orbital moon groupings we see today were formed in the distant past through this exact mechanism.

The team think this small “oddball” prograde moon could be the last-remaining remnant of a once-larger prograde-orbiting moon that formed some of the retrograde moon groupings during past head-on collisions. The name Valetudo has been proposed for it, after the Roman god Jupiter’s great-granddaughter, the goddess of health and hygiene.

Elucidating the complex influences that shaped a moon’s orbital history can teach scientists about our Solar System’s early years.

For example, the discovery that the smallest moons in Jupiter’s various orbital groups are still abundant suggests the collisions that created them occurred after the era of planet formation, when the Sun was still surrounded by a rotating disk of gas and dust from which the planets were born.

Because of their sizes — one to three kilometers — these moons are more influenced by surrounding gas and dust. If these raw materials had still been present when Jupiter’s first generation of moons collided to form its current clustered groupings of moons, the drag exerted by any remaining gas and dust on the smaller moons would have been sufficient to cause them to spiral inwards toward Jupiter. Their existence shows that they were likely formed after this gas and dust dissipated.

The initial discovery of most of the new moons were made on the Blanco 4-meter telescope at Cerro Tololo Inter-American in Chile and operated by the National Optical Astronomical Observatory of the United States. The telescope recently was upgraded with the Dark Energy Camera, making it a powerful tool for surveying the night sky for faint objects. Several telescopes were used to confirm the finds, including the 6.5-meter Magellan telescope at Carnegie’s Las Campanas Observatory in Chile; the 4-meter Discovery Channel Telescope at Lowell Observatory Arizona (thanks to Audrey Thirouin, Nick Moskovitz and Maxime Devogele); the 8-meter Subaru Telescope and the Univserity of Hawaii 2.2 meter telescope (thanks to Dave Tholen and Dora Fohring at the University of Hawaii); and 8-meter Gemini Telescope in Hawaii (thanks to Director’s Discretionary Time to recover Valetudo). Bob Jacobson and Marina Brozovic at NASA’s Jet Propulsion Laboratory confirmed the calculated orbit of the unusual oddball moon in 2017 in order to double check its location prediction during the 2018 recovery observations in order to make sure the new interesting moon was not lost.

 

Story Source:

Materials provided by Carnegie Institution for Science

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2018/07/180717101256.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Old Clusters: Birthplace of Supermassive Stars?

Cosmos by John Hussey

 

Astrophysicists may have found a solution to a problem that has perplexed scientists for more than 50 years: why are the stars in globular clusters made of material different to other stars found in the Milky Way?

Hubble Space Telescope image of the young massive star cluster R136 in the 30 Doradus star forming region in the Large Magellanic Cloud. The core of this cluster contains several very massive stars with masses of several 100 times the mass of the Sun, which could have formed by stellar collisions.

Credit: NASA, ESA, and F. Paresce (INAF-IASF, Bologna, Italy), R. O’Connell (University of Virginia, Charlottesville), and the Wide Field Camera 3 Science Oversight Committee

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

A team of international astrophysicists may have found a solution to a problem that has perplexed scientists for more than 50 years: why are the stars in globular clusters made of material different to other stars found in the Milky Way?

In a study published by Monthly Notices of the Royal Astronomical Society, the team led by the University of Surrey introduces a new actor to the equation that could solve the problem — a supermassive star.

The Milky Way galaxy hosts over 150 old globular clusters, each containing hundreds of thousands of stars densely packed together and held by gravity — these stars are almost as old as the Universe. Since the 1960s, it has been known that most stars in these clusters contain different chemical elements than all other stars in the Milky Way — these could not have been produced in the stars themselves because the required temperatures are about 10 times higher than the temperatures of the stars themselves.

The Surrey scientists argue that a supermassive star, with a mass that is tens of thousands times the mass of the Sun, formed at the same time as the globular clusters. At that time, globular clusters were filled with dense gas out of which the stars were forming. As the stars collect more and more gas, they get so close to each other that they could physically collide and form a supermassive star in a runaway collision process. The supermassive star was hot enough to produce all the observed elements and “pollute” the other stars in the cluster with the peculiar elements we observe today.

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Universe – Birth and Death of Stars

Lead-author Professor Mark Gieles of the University of Surrey said: “What is truly novel in our model is that the formation of the supermassive stars and the globular clusters are intimately linked, and this new mechanism is the first model that can form enough material to pollute the cluster, and with the correct abundances of different elements, which has been a long-standing challenge.”

The team proposes various ways to test this new model of globular clusters and supermassive star formation with existing and upcoming telescopes, which can peer deep into the regions where the globular clusters formed, when the Universe was very young.

Professor Henny Lamers, co-author of the study from the University of Amsterdam, said: “There have been many attempts to solve this problem that has puzzled astronomers for decades and I believe that this is the most promising explanation that has been proposed so far. “I am especially proud that this study is the result of a collaboration between a group of my ex-students and colleagues who are experts in different branches of astronomy.”

 

Story Source:

Materials provided by University of Surrey.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2018/06/180621101034.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Galactic Test for Existence of Dark Matter

Cosmos by John Hussey

 

A new study found a way to determine whether the mysterious ‘star putty’ really exists

Researchers used sophisticated computer simulations to devise a test that could answer a burning question in astrophysics: is there really dark matter? Or does Newton’s gravitational law need to be modified? The new study shows that the answer is hidden in the motion of the stars within small satellite galaxies swirling around the Milky Way.

This picture shows the distribution of dark matter (above) and stars (below).

Credit: © E. Garaldi, C. Porciani, E. Romano-Díaz/University of Bonn for the ZOMG Kollaboration

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

Researchers at the University of Bonn and the University of California at Irvine used sophisticated computer simulations to devise a test that could answer a burning question in astrophysics: is there really dark matter? Or does Newton’s gravitational law need to be modified? The new study, now published in the Physical Review Letters, shows that the answer is hidden in the motion of the stars within small satellite galaxies swirling around the Milky Way.

Using one of the fastest supercomputers in the world, the scientists have simulated the matter distribution of the so-called satellite “dwarf” galaxies. These are small galaxies that surround, for instance, the Milky Way or Andromeda.

The researchers focused on a relationship called “radial acceleration relation” (RAR). In disk galaxies, stars move in circular orbits around the galactic center. The acceleration that forces them to constantly change direction is caused by the attraction of matter in the galaxy. The RAR describes the relationship between this acceleration and the one caused by the visible matter only. It provides an insight into the structure of galaxies and their matter distribution.

“We have now simulated, for the first time, the RAR of dwarf galaxies on the assumption that dark matter exists,” explains Prof. Dr. Cristiano Porciani of the Argelander Institute for Astronomy at the University of Bonn. “It turned out that they behave as scaled-down versions of larger galaxies.” But what if there is no dark matter and instead gravity “works” differently than Newton thought? “In this case the RAR of dwarf galaxies depends strongly on the distance to their parent galaxy, while this does not happen if dark matter exists,” explains the researcher Emilio Romano-Díaz.

This difference makes the satellites a powerful probe for testing whether dark matter really exists. The Gaia spacecraft, which was launched by the European Space Agency (ESA) in 2013, could already provide an answer. It was designed to study the stars in the Milky Way and its satellite galaxies in unprecedented detail and has collected a large amount of data.

However, it will probably take years to solve this riddle. “Individual measurements are not enough to test the small differences we have found in our simulations,” explains doctoral student Enrico Garaldi. “But repeatedly taking a close look at the same stars improves the measurements every time. Sooner or later it should be possible to determine whether the dwarf galaxies behave like in a universe with dark matter — or not.”

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here

View Sample Video – Cosmology – Universe – Beyond the Big Bang

Related Video Content

Cosmology – Universe – Beyond the Big Bang.mp4
Cosmology – Universe – Birth and Death of Stars.webm
Cosmology – Universe – Cosmic Calendar.mp4
Cosmology – Universe – Cosmic Inflation.webm
Cosmology – Universe – Dark Matter and Dark Energy.mp4
Cosmology – Universe – Death of the Universe.mp4
Cosmology – Universe – Death Stars and their Threat to Earth.mp4
Cosmology – Universe – Do You Know What Time It Is.mp4
Cosmology – Universe – God and the Universe.mp4
Cosmology – Universe – Gravity.mp4
Cosmology – Universe – How Large is the Universe.mp4
Cosmology – Universe – Is There An Edge To the Universe.webm
Cosmology – Universe – Journey Through the Milky Way.mp4
Cosmology – Universe – Journey To The Edge Of The Universe.mp4
Cosmology – Universe – Light Speed.webm
Cosmology – Universe – Mapping the Universe.flv
Cosmology – Universe – Milky Way Galaxy Formation – Simulation.webm
Cosmology – Universe – Most of the Universe is missing.mp4
Cosmology – Universe – Nebulae.webm
Cosmology – Universe – Our Place In The Milky Way.webm
Cosmology – Universe – Parallel Universes.webm
Cosmology – Universe – Pulsars and Quasars.webm
Cosmology – Universe – Seven Ages of Starlight.webm
Cosmology – Universe – Supernovae.webm
Cosmology – Universe – The Energy of Empty Space.mp4
Cosmology – Universe – The Multiverse Theory.webm
Cosmology – Universe – The Platonic Solids.mp4
Cosmology – Universe – The Riddle of Anti Matter.mp4
Cosmology – Universe – Voyager Golden Record.mp4
Cosmology – Universe – What happened before the beginning.webm
Cosmology – Universe – What happened before the Big Bang.mp4
Cosmology – Universe – What is Reality.mp4
Cosmology – Universe – What on Earth is Wrong With Gravity.mp4

 

View Sample Video – Cosmology – Universe – Dark Matter and Dark Energy

The cement that holds galaxies together

This question is one of the most pressing issues in cosmology today. The existence of dark matter was already suggested more than 80 years ago by the Swiss astronomer Fritz Zwicky. He realized that galaxies move so fast within galaxy clusters that they should actually drift apart. He therefore postulated the presence of invisible matter which, due to its mass, exerts sufficient gravity to keep galaxies on their observed orbits. In the 1970s, his US colleague Vera Rubin discovered a similar phenomenon in spiral galaxies like the Milky Way: they rotate so quickly that the centrifugal force should tear them apart if only visible matter was present.

Today, most physicists are convinced that dark matter makes up about 80 percent of the mass in the universe. Since it does not interact with light, it is invisible to telescopes. Yet, assuming its existence provides an excellent fit to a number of other observations — such as the distribution of background radiation, an afterglow of the Big Bang. Dark matter also provides a good explanation for the arrangement and formation rate of galaxies in the universe. However, despite numerous experimental efforts, there is no direct proof that dark matter exists. This led astronomers to the hypothesis that the gravitational force itself might behave differently than previously thought. According to the theory called MOND (MOdified Newtonian Dynamics), the attraction between two masses obeys Newton’s laws only up to a certain point. At very small accelerations, such as those prevailing in galaxies, gravity becomes considerably stronger. Therefore, galaxies do not tear apart due to their rotational speed and the MOND theory can dispense with the mysterious star putty.

The new study opens up the possibility for astronomers to test these two hypotheses in an unprecedented regime.

 

Story Source:

Materials provided by University of Bonn.

 

Cosmos by John Hussey

 

https://www.sciencedaily.com/releases/2018/06/180625192745.htm

View the Cosmos – Video-eBook or Search for your Cosmos – Answer Here