Cosmologists Produce New Maps Of Dark Matter Dynamics

New maps of dark matter dynamics in the Universe have been produced by a team of international cosmologists.

Using advanced computer modelling techniques, the research team has translated the distribution of galaxies into detailed maps of matter streams and velocities for the first time.

The research was carried out by leading cosmologists from the UK, France and Germany.

Dr Florent Leclercq from the University of Portsmouth’s Institute of Cosmology and Gravitation said: “Dark matter is a substance of yet unknown nature that scientists believe makes up more than 80 per cent of the total mass of the Universe. As it does not emit or react to light, its distribution and evolution are not directly observable and have to be inferred.”

The researchers used legacy survey data obtained during 2000 — 2008 from the Sloan Digital Sky Survey (SDSS), a major three-dimensional survey of the Universe. The survey has deep multi-colour images of one fifth of the sky and spectra for more than 900,000 galaxies. The new dark matter maps cover the Northern Sky up to a distance of 600 megaparsecs, which is the equivalent of looking back about two billion years.

The researchers used a set of phase-space analysis tools and built on research from 2015, which reconstructed the initial conditions of the nearby Universe.

Dr Leclercq said: “Adopting a phase-space approach discloses a wealth of information, which was previously only analysed in simulations and thought to be inaccessible using observations.

“Accessing this information in galaxy surveys opens up new ways of assessing the validity of theoretical models in light of observations.”

The research is published in the Journal of Cosmology and Astroparticle Physics.

Large, Distant Comets More Common Than Previously Thought

that take more than 200 years to make one revolution around the sun are notoriously difficult to study. Because they spend most of their time far from our area of the solar system, many “long-period comets” will never approach the sun in a person’s lifetime. In fact, those that travel inward from the Oort Cloud — a group of icy bodies beginning roughly 300 billion kilometers away from the sun — can have periods of thousands or even millions of years.

NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft has delivered new insights about these distant wanderers. A team of astronomers led by James Bauer, a research professor of astronomy at the University of Maryland, found that there are about seven times more long-period comets measuring at least 1 kilometer across than previously predicted.

The researchers also found that long-period comets are, on average, nearly twice as large as “Jupiter family” comets, whose orbits are shaped by Jupiter’s gravity and have periods of less than 20 years. The findings were published July 14, 2017, in The Astronomical Journal.

“The number of comets speaks to the amount of material left over from the solar system’s formation,” Bauer said. “We now know that there are more relatively large chunks of ancient material coming from the Oort Cloud than we thought.”

The Oort Cloud is too distant to be seen by current telescopes, but is thought to be a spherical distribution of small icy bodies at the outermost edge of the solar system. The density of comets within it is low, so the odds of comets colliding within it are low. Long-period comets that WISE observed probably got kicked out of the Oort Cloud millions of years ago. The observations were carried out in 2010 during the spacecraft’s primary mission, before it was renamed NEOWISE and reactivated to target near-Earth objects (NEOs) in 2013.

“Our study is a rare look at objects perturbed out of the Oort Cloud,” said Amy Mainzer, a co-author of the study based at NASA’s Jet Propulsion Laboratory in Pasadena, California and principal investigator of the NEOWISE mission. “They are the most pristine examples of what the solar system was like when it formed.”

Astronomers already had broader estimates of how many long-period and Jupiter family comets are in our solar system, but had no good way of measuring the sizes of long-period comets. This is because the cloud of gas and dust that surrounds each comet — known as a coma — appears hazy in images and obscures the comet’s nucleus.

By using WISE data that shows the infrared glow of the coma, the scientists were able to “subtract” the coma from each comet and estimate the size of the nucleus. The data came from WISE observations of 164 cometary bodies — including 95 Jupiter family comets and 56 long-period comets.

The results reinforce the idea that comets that pass by the sun more frequently tend to be smaller than those spending much more time away from the sun. That is because Jupiter family comets get more heat exposure, which causes volatile substances like water to sublimate and drag away other material from the comet’s surface as well.

“Our results mean there’s an evolutionary difference between Jupiter family and long-period comets,” Bauer said.

The existence of so many more long-period comets than predicted suggests that more of them have likely impacted planets, delivering icy materials from the outer reaches of the solar system.

Researchers also found clustered orbits among the long-period comets they studied, suggesting there could have been larger bodies that broke apart to form these groups.

The results will be important for assessing the likelihood of comets impacting our solar system’s planets, including Earth.

“Comets travel much faster than asteroids, and some of them are very big,” Mainzer said. “Studies like this will help us define what kind of hazard long-period comets may pose.”

NASA’s Jet Propulsion Laboratory in Pasadena, California, managed and operated WISE for NASA’s Science Mission Directorate in Washington, D.C. The NEOWISE project is funded by the Near-Earth Object Observation Program, now part of NASA’s Planetary Defense Coordination Office. The spacecraft was put into hibernation mode in 2011 after twice scanning the entire sky, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA’s efforts to identify potentially hazardous near-Earth objects.

Venus’s Turbulent Atmosphere

Venus is often referred to as Earth’s twin because both planets share a similar size and surface composition. Also, they both have atmospheres with complex weather systems. But that is about where the similarities end: Venus is one the most hostile places in our solar system. Its atmosphere consists of 96.5 percent carbon dioxide, with surface temperatures of constantly about 500 degrees Celsius. Venus is a slowly rotating planet — it needs about 243 terrestrial days to complete one rotation. We would expect its atmosphere to rotate with the same rhythm, but in fact it takes only four days. This phenomenon is called superrotation, and it causes substantial turbulences in the planet’s atmosphere. The scientists do not yet fully understand its origin and motor, but are working on an answer to this puzzle. The many waves in the planet’s atmosphere may play an important role.

The research results were generated by an international collaboration headed by the Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA). Experts in space and astronautical science and astrophysics from universities and institutions in Japan, Spain, Italy, and Germany are cooperating in the project. From Germany, the Rhenish Institute for Environmental Research at the University of Cologne and the Center for Astronomy and Astrophysics at Technische Universität Berlin are involved.

The research team analysed data generated by the spacecraft Venus Express to investigate components of Venus’s complex atmosphere, including thermal measurements with regard to horizontal and vertical wave patterns. The data also included first global measurements from the tracking of individual features in thermal emission images at 3.8 and 5.0 ?m (micrometer) during 2006-2008 and 2015.

Vertical information in unison with horizontal data help to understand the nature of the ob-served wave patterns. The vertical information from the VeRa instrument (an atmosphere experiment where radio waves sent by spacecraft Venus Express are being analysed) could help to identify the observed waves as gravity waves. This, in turn, is crucial for the analysis of atmospheric processes.

Dr. Silvia Tellmann is Vice-Director of the Department of Planetary Research at the Rhenish Institute for Environmental Research at the University of Cologne. She is an expert on the structure, dynamics, and circulation of planetary atmospheres and a co-author of the study. ‘We were able to relate the stationary gravity waves found at higher altitudes with the surface elevations of Venus’, she says. ‘Hence, the waves can be explained with wind currents caused by topographical obstacles. We assume that these stationary waves are substantial for the continuity of the superrotation in the atmosphere of Venus.’

BREAKING NEWS: August 21st Full Solar Eclipse Geographical Areas of Concern

I have highlighted areas of concern as related to the causal effects of a total solar eclipse. If tectonics are at their tipping point, it would not take much to set them off. As mentioned, it is mostly the rapid temperature change which causes an expansion and contraction of Earth’s lithosphere, even if ever so slight.

Most ‘mantle plumes’ as well as volcanoes are sub-marine (ocean bottom); hence the rapid shift in ocean temperatures is also prone to set off a rippling effect which is often unpredictable due to the spider webbing tentacles which connect a system of mantle plumes and volcanoes.

A mantle plume is a large column of hot rock (magma) mostly originating from Earth’s core-mantle boundary. This flow of viscous material rises through the mantle, asthenosphere, and lithosphere finding its way to Earth’s surface or crust. The expanding or contracting movement of these events are the cause of earthquakes and volcanoes. The surface includes ocean bottoms causing an increase of ocean temperatures, which in-turn destabilizing the atmosphere contributing to forming or escalation of tropical storms or hurricanes.

Next article will address perhaps a less scientific direction which suggest the current mode of global political dysfunction, may have some roots in history showing a pattern of “what happens below, reflects what happens above”. This suggest the turmoil which results from earth changing events appears to be in-sync with emotional unrest. Continued scientific data will of course follow.

Watch for ongoing reports as information comes in. I also plan to present greater outlines to the science behind by research, especially for those who may be new to my work.

 

Moon Has A Water-Rich Interior

A new study of satellite data finds that numerous volcanic deposits distributed across the surface of the Moon contain unusually high amounts of trapped water compared with surrounding terrains. The finding of water in these ancient deposits, which are believed to consist of glass beads formed by the explosive eruption of magma coming from the deep lunar interior, bolsters the idea that the lunar mantle is surprisingly water-rich.

Scientists had assumed for years that the interior of the Moon had been largely depleted of water and other volatile compounds. That began to change in 2008, when a research team including Brown University geologist Alberto Saal detected trace amounts of water in some of the volcanic glass beads brought back to Earth from the Apollo 15 and 17 missions to the Moon. In 2011, further study of tiny crystalline formations within those beads revealed that they actually contain similar amounts of water as some basalts on Earth. That suggests that the Moon’s mantle — parts of it, at least — contain as much water as Earth’s.

“The key question is whether those Apollo samples represent the bulk conditions of the lunar interior or instead represent unusual or perhaps anomalous water-rich regions within an otherwise ‘dry’ mantle,” said Ralph Milliken, lead author of the new research and an associate professor in Brown’s Department of Earth, Environmental and Planetary Sciences. “By looking at the orbital data, we can examine the large pyroclastic deposits on the Moon that were never sampled by the Apollo or Luna missions. The fact that nearly all of them exhibit signatures of water suggests that the Apollo samples are not anomalous, so it may be that the bulk interior of the Moon is wet.”

The research, which Milliken co-authored with Shuai Li, a postdoctoral researcher at the University of Hawaii and a recent Brown Ph.D. graduate, is published in Nature Geoscience.

Detecting the water content of lunar volcanic deposits using orbital instruments is no easy task. Scientists use orbital spectrometers to measure the light that bounces off a planetary surface. By looking at which wavelengths of light are absorbed or reflected by the surface, scientists can get an idea of which minerals and other compounds are present.

The problem is that the lunar surface heats up over the course of a day, especially at the latitudes where these pyroclastic deposits are located. That means that in addition to the light reflected from the surface, the spectrometer also ends up measuring heat.

“That thermally emitted radiation happens at the same wavelengths that we need to use to look for water,” Milliken said. “So in order to say with any confidence that water is present, we first need to account for and remove the thermally emitted component.”

To do that, Li and Milliken used laboratory-based measurements of samples returned from the Apollo missions, combined with a detailed temperature profile of the areas of interest on the Moon’s surface. Using the new thermal correction, the researchers looked at data from the Moon Mineralogy Mapper, an imaging spectrometer that flew aboard India’s Chandrayaan-1 lunar orbiter.

The researchers found evidence of water in nearly all of the large pyroclastic deposits that had been previously mapped across the Moon’s surface, including deposits near the Apollo 15 and 17 landing sites where the water-bearing glass bead samples were collected.

“The distribution of these water-rich deposits is the key thing,” Milliken said. “They’re spread across the surface, which tells us that the water found in the Apollo samples isn’t a one-off. Lunar pyroclastics seem to be universally water-rich, which suggests the same may be true of the mantle.”

The idea that the interior of the Moon is water-rich raises interesting questions about the Moon’s formation. Scientists think the Moon formed from debris left behind after an object about the size of Mars slammed into the Earth very early in solar system history. One of the reasons scientists had assumed the Moon’s interior should be dry is that it seems unlikely that any of the hydrogen needed to form water could have survived the heat of that impact.

“The growing evidence for water inside the Moon suggest that water did somehow survive, or that it was brought in shortly after the impact by asteroids or comets before the Moon had completely solidified,” Li said. “The exact origin of water in the lunar interior is still a big question.”

In addition to shedding light on the water story in the early solar system, the research could also have implications for future lunar exploration. The volcanic beads don’t contain a lot of water — about .05 percent by weight, the researchers say — but the deposits are large, and the water could potentially be extracted.

“Other studies have suggested the presence of water ice in shadowed regions at the lunar poles, but the pyroclastic deposits are at locations that may be easier to access,” Li said. “Anything that helps save future lunar explorers from having to bring lots of water from home is a big step forward, and our results suggest a new alternative.”

Strength Of Tectonic Plates May Explain Shape Of The Tibetan Plateau

Geoscientists have long puzzled over the mechanism that created the Tibetan Plateau, but a new study finds that the landform’s history may be controlled primarily by the strength of the tectonic plates whose collision prompted its uplift. Given that the region is one of the most seismically active areas in the world, understanding the plateau’s geologic history could give scientists insight to modern day earthquake activity.

The new findings are published in the journal Nature Communications.

Even from space, the Tibetan Plateau appears huge. The massive highland, formed by the convergence of two continental plates, India and Asia, dwarfs other mountain ranges in height and breadth. Most other mountain ranges appear like narrow scars of raised flesh, while the Himalaya Plateau looks like a broad, asymmetrical scab surrounded by craggy peaks.

“The asymmetric shape and complex subsurface structure of the Tibetan Plateau make its formation one of the most significant outstanding questions in the study of plate tectonics today,” said University of Illinois geology professor and study co-author Lijun Liu.

In the classic model of Tibetan Plateau formation, a fast-moving Indian continental plate collides head-on with the relatively stationary Asian plate about 50 million years ago. The convergence is likely to have caused the Earth’s crust to bunch up into the massive pile known as the Himalaya Mountains and Tibetan Plateau seen today, but this does not explain why the plateau is asymmetrical, Liu Said.

“The Tibetan Plateau is not uniformly wide,” said Lin Chen, the lead author from the Chinese Academy of Sciences. “The western side is very narrow and the eastern side is very broad — something that many past models have failed to explain.”Many of those past models have focused on the surface geology of the actual plateau region, Liu said, but the real story might be found further down, where the Asian and Indian plates meet.

“There is a huge change in topography on the plateau, or the Asian plate, while the landform and moving speed of the Indian plate along the collision zone are essentially the same from west to east,” Liu said. “Why does the Asian plate vary so much?”

To address this question, Liu and his co-authors looked at what happens when tectonic plates made from rocks of different strengths collide. A series of 3-D computational continental collision models were used to test this idea.

“We looked at two scenarios — a weak Asian plate and a strong Asian plate,” said Liu. “We kept the incoming Indian plate strong in both models.”

When the researchers let the models run, they found that a strong Asian plate scenario resulted in a narrow plateau. The weak Asian plate model produced a broad plateau, like what is seen today.

“We then ran a third scenario which is a composite of the strong and weak Asian plate models,” said Liu. “An Asian plate with a strong western side and weak eastern side results in an orientation very similar to what we see today.”

This model, besides predicting the surface topography, also helps explain some of the complex subsurface structure seen using seismic observation techniques.

“It is exciting to see that such a simple model leads to something close to what we observe today,” Liu said. “The location of modern earthquake activity and land movement corresponds to what we predict with the model, as well.”

JUST IN: Large CME on Farside of Sun

A large CME occurred on the farside of the Sun beginning at approximately 03:20 UTC (July 23rd). Shortly afterwards, a fast moving, asymmetric halo coronal mass ejection (CME) became visible in LASCO coronagraph imagery.

Because the flare location was situated on the farside of the Sun, the energetic plasma cloud was directed away from Earth. Had it been directed our way, severe geomagnetic storming would have been likely.

This event is actually helpful in disrupting the far more dangerous galactic cosmic rays from entering Earth’s atmosphere. It is the very reason the Sun is in an extreme solar minimum, that is allowing up to a 20% increase in dose rates of cosmic rays.

Thank you for helping support this project to keep us informed of the latest research and breaking news. I need to register with specific journals and research sites which average about $100 each. I would also like to attend one or two symposiums attended by the top scientists in the world, who will present their latest research regarding these topics – and before it ever hits the journals or news organizations.

My next article will outline the geographic areas most vulnerable to coming events.

Watch for ongoing reports as information comes in. I also plan to present greater outlines to the science behind by research, especially for those who may be new to my work.

Cheers, Mitch