суббота, 13 июля 2019 г.

Schorl Tourmaline | #Geology #GeologyPage #Mineral Locality:…

Schorl Tourmaline | #Geology #GeologyPage #Mineral

Locality: Erongo Mountains, Erongo Region, Namibia, Africa

Dimensions: 7.9 × 6.0 × 4.5 cm

Photo Copyright © Crystal Classics

Geology Page



Holes in the universe sharpen cosmic measurements

Regions of the Universe containing very few or no galaxies — known as voids — can help measure cosmic expansion with much greater precision than before, according to new research.

Holes in the universe sharpen cosmic measurements
The change in the average shape of voids caused by Doppler distortions and the effects of dark energy
and curvature [Credit: Dr. Seshadri Nadathur/University of Portsmouth]

The study looked at the shapes of voids found in data from the Sloan Digital Sky Survey (SDSS) collaboration. Voids come in a variety shapes, but because they have no preferred direction of alignment, a large enough sample of them can on average be used as «standard spheres» — objects which should appear perfectly symmetric in the absence of any distortions.

However, the observed shapes of these spheres are distorted by Doppler shifts in the redshifts of nearby galaxies caused by the local velocity field, and by the nature and amounts of dark matter and dark energy that make up 95% of the Universe. This distortion can be theoretically modelled, and the new work shows it can now be precisely measured.

The research was led by the University of Portsmouth, a world leader in cosmology, and is published this week in Physical Review D.

The new measurement of the distortion around voids used the Baryon Oscillation Spectroscopic Survey (BOSS) of galaxies from SDSS, that was designed to measure dark energy and the curvature of space.

For measuring a key aspect of the cosmic expansion, the new method greatly outperforms the standard baryon acoustic oscillation (BAO) technique that BOSS was designed for. The new results agree with the simplest model of a flat Universe with a cosmological constant dark energy, and tighten the constraints on alternative theories.

Lead author, Dr Seshadri Nadathur, research fellow at the University’s Institute of Cosmology and Gravitation (ICG), said: «This measurement tremendously upgrades the previous best results from BOSS — the precision is equivalent to getting data from a hypothetical survey four times as large as BOSS, completely for free. It really helps pin down the properties of dark energy.»

«These results also mean that the expected science results from facilities such as the European Space Agency’s Euclid satellite mission and the Dark Energy Spectroscopic Instrument — in which the astronomy community have invested a lot of resources — can be even better than previously thought.»

Source: University of Portsmouth [July 10, 2019]



Pair of supermassive black holes discovered on a collision course

Astronomers have spotted a distant pair of titanic black holes headed for a collision. Each black hole’s mass is more than 800 million times that of our sun. As the two gradually draw closer together in a death spiral, they will begin sending gravitational waves rippling through space-time. Those cosmic ripples will join the as-yet-undetected background noise of gravitational waves from other supermassive black holes.

Pair of supermassive black holes discovered on a collision course
A galaxy roughly 2.5 billion light-years away has a pair of supermassive black holes (inset). The locations of the
 black holes are lit up by warm gas and bright stars that surround the objects. The finding improves estimates
of when astronomers will first detect gravitational wave background generated by supermassive black holes
[Credit: A.D. Goulding et al. 2019]

Even before the destined collision, the gravitational waves emanating from the supermassive black hole pair will dwarf those previously detected from the mergers of much smaller black holes and neutron stars.

«Supermassive black hole binaries produce the loudest gravitational waves in the universe,» says co-discoverer Chiara Mingarelli, an associate research scientist at the Flatiron Institute’s Center for Computational Astrophysics in New York City. Gravitational waves from supermassive black hole pairs «are a million times louder than those detected by LIGO.»

The study was led by Andy Goulding, an associate research scholar at Princeton University. Goulding, Mingarelli and collaborators from Princeton and the U.S. Naval Research Laboratory in Washington, D.C., report the discovery in The Astrophysical Journal Letters.

The two supermassive black holes are especially interesting because they are around 2.5 billion light-years away from Earth. Since looking at distant objects in astronomy is like looking back in time, the pair belong to a universe 2.5 billion years younger than our own. Coincidentally, that’s roughly the same amount of time the astronomers estimate the black holes will take to begin producing powerful gravitational waves.

In the present-day universe, the black holes are already emitting these gravitational waves, but even at light speed the waves won’t reach us for billions of years. The duo is still useful, though. Their discovery can help scientists estimate how many nearby supermassive black holes are emitting gravitational waves that we could detect right now.

Detecting the gravitational wave background will help resolve some of the biggest unknowns in astronomy, such as how often galaxies merge and whether supermassive black hole pairs merge at all or become stuck in a near-endless waltz around each other.

«It’s a major embarrassment for astronomy that we don’t know if supermassive black holes merge,» says study co-author Jenny Greene, a professor of astrophysical sciences at Princeton. «For everyone in black hole physics, observationally this is a long-standing puzzle that we need to solve.»

Supermassive black holes contain millions or even billions of suns’ worth of mass. Nearly all galaxies, including the Milky Way, contain at least one of the behemoths at their core. When galaxies merge, their supermassive black holes meet up and begin orbiting one another. Over time, this orbit tightens as gas and stars pass between the black holes and steal energy.

Once the supermassive black holes get close enough, though, this energy theft all but stops. Some theoretical studies suggest that black holes then stall at around 1 parsec (roughly 3.2 light-years) apart. This slowdown lasts nearly indefinitely and is known as the final parsec problem. In this scenario, only very rare groups of three or more supermassive black holes result in mergers.

Astronomers can’t just look for stalled pairs because long before the black holes are 1 parsec apart, they’re too close to distinguish as two separate objects. Moreover, they don’t produce strong gravitational waves until they overcome the final-parsec hurdle and get closer together. (Observed as they were 2.5 billion years ago, the newfound supermassive black holes appear about 430 parsecs apart.)

If the final parsec problem doesn’t exist, then astronomers expect that the universe is filled with the clamor of gravitational waves from supermassive black hole pairs. «This noise is called the gravitational wave background, and it’s a bit like a chaotic chorus of crickets chirping in the night,» says Goulding. «You can’t discern one cricket from another, but the volume of the noise helps you estimate how many crickets are out there.» (When two supermassive black holes finally collide and combine, they send out a thundering chirp that dwarfs all others. Such an event is brief and extraordinarily rare, though, so scientists don’t expect to detect one any time soon.)

The gravitational waves generated by supermassive black hole pairs are outside the frequencies currently observable by experiments such as LIGO and Virgo. Instead, gravitational wave hunters rely on arrays of special stars called pulsars that act like metronomes. The rapidly spinning stars send out radio waves in a steady rhythm. If a passing gravitational wave stretches or compresses the space between Earth and the pulsar, the rhythm is slightly thrown off.

Detecting the gravitational wave background using one of these pulsar timing arrays takes patience and plenty of monitored stars. A single pulsar’s rhythm might be disrupted by only a few hundred nanoseconds over a decade. The louder the background noise, the bigger the timing disruption and the sooner the first detection will be made.

Goulding, Greene and the other observational astronomers on the team detected the two titans with the Hubble Space Telescope. Although supermassive black holes aren’t directly visible through an optical telescope, they are surrounded by bright clumps of luminous stars and warm gas drawn in by the powerful gravitational tug. For its time in history, the galaxy harboring the newfound supermassive black hole pair «is basically the most luminous galaxy in the universe,» Goulding says. What’s more, the galaxy’s core is shooting out two unusually colossal plumes of gas. After the researchers pointed the Hubble Space Telescope at the galaxy to uncover the origins of its spectacular gas clouds, they discovered that the system contained not one but two massive black holes.

The observationalists then teamed up with gravitational wave physicists Mingarelli and Princeton graduate student Kris Pardo to interpret the finding in the context of the gravitational wave background. The discovery provides an anchor point for estimating how many supermassive black hole pairs are within detection distance of Earth. Previous estimates relied on computer models of how often galaxies merge, rather than actual observations of supermassive black hole pairs.

Based on the findings, Pardo and Mingarelli predict that in an optimistic scenario there are about 112 nearby supermassive black holes emitting gravitational waves. The first detection of the gravitational wave background from supermassive black holes should therefore come within the next five years or so. If such a detection isn’t made, that would be evidence that the final parsec problem may be insurmountable. The team is currently looking at other galaxies similar to the one harboring the newfound supermassive black hole pair. Finding additional pairs will help them further hone their predictions.

Author: Thomas Sumner | Source: Simons Foundation [July 10, 2019]



Astronomers expand cosmic ‘cheat sheet’ in hunt for life

Using nature’s color palette from early Earth, Cornell University astronomers have created a cosmic «cheat sheet» in order to understand where discovered exoplanets may fall along their own evolutionary spectrum.

Astronomers expand cosmic 'cheat sheet' in hunt for life
To understand where exoplanets are in their own evolution, astronomers can use Earth’s biological milestones
as a Rosetta stone [Credit: Wendy Kenigsberg/Cornell Brand Communications]

Jack O’Malley-James, a research associate at the Carl Sagan Institute, and Lisa Kaltenegger, professor of astronomy and director of the Carl Sagan Institute, co-authored «Expanding the Timeline for Earth’s Photosynthetic Red Edge Biosignature» published in The Astrophysical Journal Letters.

«In our search to understand exoplanets, we’re using the early Earth and its biological milestones in history as a Rosetta stone,» O’Malley-James said. «Scientists can observe surface biosignatures beyond vegetation on Earth-like exoplanets by using our own planet as the key for what to look for.»

For the last half-billion years — roughly 10 percent of our planet’s lifetime — chlorophyll, present in many familiar forms of plant life such as leaves and lichen, has been the key component in Earth’s biosignature. But other flora, such as cyanobacteria and algae, are much older than land-based vegetation, but their chlorophyll-containing structures leave their own telltale signs on a planet’s surface.

«Astronomers had concentrated only on vegetation before, but with a better color palette, researchers can now look beyond a half-billion years and up to 2.5 billion years back on Earth’s history to match like periods on exoplanets,» Kaltenegger said. «If an alien had used color to observe if our Earth had life, that alien would see very different colors throughout our planet’s history — going back billions of years — when different life forms dominated Earth’s surface.»

O’Malley-James and Kaltenegger modeled spectra of Earth-like exoplanets with different surface organisms that use chlorophyll.

Lichens (a symbiotic fungal and photosynthetic partnership) may have colonized Earth’s land masses some 1.2 billion years ago and would have painted Earth in sage to mint green colors. This coverage would have generated a «nonvegetative» photosynthetic red-edge signature. A red-edge signature is the part of the spectrum that helps keep plants from getting burned by the sun.

«When we discover an exoplanet, this research gives us a much wider range to look back in time,» Kaltenegger said. «We extend the time that we can find surface biota from 500 million years (widespread land vegetation) to about 1 billion years ago with lichen and up to 2 or 3 billion years ago with cyanobacteria.»

Author: Blaine Friedlander | Source: Cornell University [July 10, 2019]



Art ring charged with smuggling $143 million in antiquities

An art dealer who authorities called one of the most prolific smugglers in the world and seven others were charged with trafficking more than $140 million in stolen antiquities, prosecutors said Wednesday.

Art ring charged with smuggling $143 million in antiquities
Three of the items seized by the Department of Homeland Security during the course of the investigation
into Subhash Kapoor and his co-defendants [Credit: Manhattan District Attorney’s Office]

Authorities described the case as one of the largest of its kind, saying the conspiracy began more than three decades ago and involved more than 2,600 recovered artifacts, including statues and ancient masterworks.

A criminal complaint filed in Manhattan state court said the smuggling was orchestrated by Subhash Kapoor, a New York art gallery owner who was arrested in Germany in 2011 and later extradited to India, where he faces similar charges. An email seeking comment was sent to Kapoor’s defense attorney.

The prosecution involves artifacts stolen from Afghanistan, Cambodia, India, Pakistan and other countries that were sold for profit to dealers and collectors around the world. Some of the items appeared in world-renowned museums without officials realizing they were ill-gotten gains.

“These are, in many instances, priceless works that represent the culture and history of the countries from which they were stolen,” Manhattan District Attorney Cyrus R. Vance Jr. told The Associated Press in an interview. “They are of enormous value.”

In all, authorities said, the network trafficked more than $143 million worth of antiquities. The international investigation was called “Operation Hidden Idol.”

The U.S. Department of Homeland Security has described Kapoor as “one of the most prolific art smugglers in the world.” He faces 86 counts in the criminal complaint, including grand larceny and criminal possession of stolen property.

Art ring charged with smuggling $143 million in antiquities
A sandstone stele of Rishabhanata from the 10th century, believed looted, seized in a raid of Christie’s
as part of an international investigation into former dealer Subhash Kapoor
[Credit: Department of Homeland Security]

The lead prosecutor, Matthew Bogdanos, told the AP that none of the defendants is believed to be in the United States. He said the authorities asked Interpol to issue international warrants for their arrest.

Kapoor, 70, owned the Art of the Past gallery on Manhattan’s Upper East Side, which authorities raided in early 2012.

The criminal complaint says Kapoor went to extraordinary lengths to acquire the artifacts, many of them statues of Hindu deities, and then falsified their provenance with forged documents.

It says Kapoor traveled the world seeking out antiquities that had been looted from temples, homes and archaeological sites.

Some of the artifacts were recovered from Kapoor’s storage units in New York.

Prosecutors said Kapoor had the items cleansed and repaired to remove any damage from illegal excavation, and then illegally exported them to the United States from their countries of origin.

“Kapoor would also loan stolen antiquities to major museums and institutions,” the complaint says, “creating yet another false veneer of legitimacy by its mere presence in otherwise reputable museums and institutions.”

The other defendants in the case include suppliers and restorers accused of conspiring with Kapoor.

Author: Jim Mustian | AP News [July 11, 2019]



Layout of historic Nubian city revealed

Polish archaeologists have gained an insight into the 18th century layout of an old city in what is now Sudan using geophysical research.

Layout of historic Nubian city revealed
Given the site’s size, archaeologists were unable to examine all of it using traditional excavation methods so turned
to geophysical methods, which involve using quantitative methods to analyse physical processes
and properties of the Earth [Credit: S. Lenarczyk]

Located on the east of bank of the Nile, Old Dongola was the capital of Makuria, a Nubian kingdom that existed in what is now Northern Sudan and Southern Egypt from the 6th to the 15th century.
A Polish archaeological mission from the University of Warsaw’s Centre for Mediterranean Archaeology has been working in Old Dongola since 1964.

Layout of historic Nubian city revealed
A Polish archaeological mission from the University of Warsaw’s Centre for Mediterranean Archaeology
has been working in Old Dongola since 1964 [Credit: PCMA UW (CAS UW)]

In 2017, the team led by Dr Artur Obłuski received a European Research Council for a project entitled “UMMA: Urban Metamorphosis of the community of a Medieval African Capital City”.
Now the archaeologists have shown that the city outlasted the change in power, surviving until the early 19th century, when it fell suddenly, reports Science in Poland (Nauke w Polsce).

Layout of historic Nubian city revealed
Fieldwork in Old Dongola [Credit: M. Reklajtis/PCMA UW (CAS UW)]

Given the site’s size, the archaeologists were unable to examine all of it using traditional excavation methods. Instead, they turned to geophysical methods, which involve using quantitative methods to analyse physical processes and properties of the Earth.
The geophysical research, encompassing magnetic and ground-penetrating radar methods, was carried out by Tomasz Herbich and Robert Ryndziewicz, experts at the Polish Academy of Sciences’ Institute of Archaeology and Ethnography. The resulting images showed the city’s layout shortly before its downfall.

Layout of historic Nubian city revealed
A citadel and adjacent area with a mosque, which before 1316 was a throne room
[Credit: S. Lenarczyk]

“Based on my preliminary search, it appears that we do not have such data for any other city from this period in Africa,” said Obłuski.
The geophysical research also showed that the city’s walls changed function over time. Initially, they served to protect the city; later, they separated different districts from each other.

Layout of historic Nubian city revealed
Excavations in Dongola reveal remains of 18th-century housing
[Credit: M. Reklajtis/CAS UW]

In addition to geophysical methods, the archaeologists conducted a broad survey of excavations, covering almost half a hectare over the past season. Their findings suggest that the city’s residents had a relatively high standard of living – as suggested by ceramics from Japan and pipes found on site.

“Interestingly, in the 18th Century Dongola’s inhabitants were probably heavy smokers. We found a few pipes in every house, and tobacco was not a cheap good at the time,” Obłuski observed.

Author: Anne Chatham | Source: The First News [July 11, 2019]



22 ancient Greek amphorae found off Albanian coast

A joint Albanian-American underwater archaeology project says it has found amphorae that are at least 2,500 years old in the Ionian Sea off the Albanian coast, which might yield an ancient shipwreck.

22 ancient Greek amphorae found off Albanian coast
An amphora which dates from between the 7th and 5th centuries BC stands underwater near the shores
of the Karaburun peninsula, Albania [Credit: RPM Nautical Foundation via AP]

The research vessel Hercules of the RPM Nautical Foundation said Friday they had found 22 amphorae—a two-handled jar with a narrow neck used for wine or oil—40-60 meters deep scattered around the seabed close to a rocky shores near the Karaburun peninsula.

Archaeologist Mateusz Polakowski said they believe the Corinthian A type amphorae date to between the 7th and the 5th century B.C.

«If the remains of a wreck can be found, it will put this discovery as the earliest ship ever to be sailing along the Albanian coast,» said Polakowski.

RPM chairman James Goold considered the site as «one of the most important of all of our discoveries … (and) it will be very important from a historical and archaeological perspective» if confirmed. Further investigation of the site will be necessary.

Albanian archaeologist Neritan Ceka said similar wine amphorae of Corinthian and Kerkyra origin have been found in Durres (historically known as Epidamnos and Dyrrachium) and Apollonia and other inland areas in Albania, something which indicates the intensive trade during the second half of the 7th century BC along the Albanian coast.

Since 2004, RPM has mapped Albania’s offshore seabed for ancient and modern shipwrecks, with ongoing plans to open an underwater museum in western Albania.

«It certainly would be a great starting point for a national program around which to establish a museum and show the pivotal role of Albania in antiquity,» said Goold.

Ceka said Albanian authorities are planning a new four-to-five-year project with RPM and the Texas-based not-for-profit Institute of Nautical Archaeology, to explore the possibilities of excavating shipwrecks, a financially expensive and scientifically delicate process.

The research in Albania has so far uncovered 28 wreck sites as well as several amphora mounds and additional finds all the way from southernmost Sarande and Butrint to Durres and it is planning to go north of Durres afterward.

RPM’s presence in the last 12 years has been a «huge step» to Albania’s science of underwater archaeology, according to Auron Tare, UNESCO head of the Scientific and Technical Committee for World Underwater Heritage.

«If confirmed this ship wreck can be associated with the foundation of two major cities in Albanian coastline, Dyrrachium and Apollonia, both the gates of Via Egnatia, the ancient road to the eastern trade,» said Tare.

«We have discovered not only ancient shipwrecks but also a good number of WWI and WWII shipwrecks shedding light to an unknown chapter of our history,» said Tare.

Albania is trying to protect and capitalize on its rich underwater heritage, with scant funding for its preservation from the government one of Europe’s poorest nations.

Author: Llazar Semini | Source: The Associated Press [July 12, 2019]



2019 July 13 The Eagle Rises Image Credit: Apollo 11, NASA -…

2019 July 13

The Eagle Rises
Image Credit: Apollo 11, NASA — Stereo Image Copyright: John Kaufmann (ALSJ)

Explanation: Get out your red/blue glasses and check out this stereo view from lunar orbit. The 3D anaglyph was created from two photographs (AS11-44-6633, AS11-44-6634) taken by astronaut Michael Collins during the 1969 Apollo 11 mission. It features the lunar module ascent stage, dubbed The Eagle, rising to meet the command module in lunar orbit on July 21. Aboard the ascent stage are Neil Armstrong and Buzz Aldrin, the first to walk on the Moon. The smooth, dark area on the lunar surface is Mare Smythii located just below the equator on the extreme eastern edge of the Moon’s near side. Poised beyond the lunar horizon is our fair planet Earth.

∞ Source: apod.nasa.gov/apod/ap190713.html

Tealing Prehistoric Soutterrain Tealing, Angus, 7.7.19.

Tealing Prehistoric Soutterrain Tealing, Angus, 7.7.19.

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NASA Finds an Asymmetric Tropical Storm Barry

NASA — EOS Aqua Mission logo.

July 12, 2019

Barry (was TD2) – Atlantic Ocean

Infrared imagery from NASA’s Aqua satellite shows that Tropical Storm Barry doesn’t look like a typical strong tropical cyclone. Imagery revealed that Barry is elongated and the strongest storms were south of it’s stretched out center of circulation.  

Image above: On July 12 at 4:10 a.m. EDT (0810 UTC) the MODIS instrument that flies aboard NASA’s Aqua satellite showed strongest storms in Tropical Storm Barry were south of the elongated center where cloud top temperatures were as cold as minus 70 degrees Fahrenheit (minus 56.6 Celsius). Image Credits: NASA/NRL.

Warnings and Watches

At 8 a.m. EDT (1200 UTC) on Friday, July 12, NOAA’s National Hurricane Center (NHC) in Miami, Florida said that Barry is moving slowly to the west-northwest in the Gulf of Mexico, and south of the coast of southeastern Louisiana. NHC warns of dangerous storm surge, heavy rains, and wind conditions expected across the north-central Gulf coast.

Many warnings and watches are in effect as Barry hugs that northern Gulf coast, hammering the region. A Hurricane Warning is in effect from Intracoastal City to Grand Isle, Louisiana. A Tropical Storm Warning is in effect from the mouth of the Pearl River to Grand Isle, La. and for Lake Pontchartrain and Lake Maurepas including metropolitan New Orleans, and from Intracoastal City, Louisiana to Cameron, Louisiana.

A Storm Surge Warning is in effect from Intracoastal City to Shell Beach, Louisiana. A Storm Surge Watch is in effect from Shell Beach to the Mississippi/Alabama border and for Lake Pontchartrain. A Hurricane Watch is in effect from the mouth of the Mississippi River to Grand Isle, La. and for Intracoastal City to Cameron, La. A Tropical Storm Watch is in effect from east of the Mouth of the Pearl River to the Mississippi/Alabama border.

Satellite Imagery

NASA’s Aqua satellite used infrared light to analyze the strength of storms and found the bulk of them in the southern quadrant. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

On July 12 at 4:10 a.m. EDT (0810 UTC),  the Moderate Imaging Spectroradiometer or MODIS instrument that flies aboard NASA’s Aqua satellite gathered infrared data on Tropical Storm Barry. Strongest thunderstorms had cloud top temperatures as cold as minus 70 degrees Fahrenheit (minus 56.6 Celsius). Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall. Those strongest storms were south and southeast of the center of the elongated circulation.

EOS Aqua satellite. Image Credit: NASA

The NHC said, “Barry does not have the typical presentation of a tropical cyclone on satellite imagery at this time. The cloud pattern consists of a cyclonically curved convective band on the southern semicircle, and the system is devoid of an inner convective core near the center. Barry is an asymmetric storm with most of the tropical-storm-force winds occurring in the eastern semicircle. Tropical-storm-force winds extend outward up to 175 miles (280 km) to the east of the center.”

Barry’s Status on July 12, 2019 at 8 a.m. EDT

On July 12 at 8 a.m. EDT (1200 UTC), the National Hurricane Center (NHC) said the broad circulation center of Tropical Storm Barry was located near latitude 28.2 degrees north and longitude 90.3 degrees west. The minimum central pressure based on the Hurricane Hunter aircraft data is 998 millibars (29.47 inches).

Barry is moving toward the west-northwest near 5 mph (7 kph). A track toward the northwest is expected to begin later in the day on Friday, July 12, followed by a turn toward the north on Saturday, July 13.

Reports from NOAA and Air Force Reserve Hurricane Hunter aircraft indicate that the maximum sustained winds remain near 50 mph (85 kph) with higher gusts. Some strengthening is expected during the next day or so, and Barry could become a hurricane tonight or early on July 13 when the center is near the Louisiana coast. After landfall, weakening is expected after Barry moves inland.

Barry’s Path Forward

On the NHC forecast track, the center of Barry will be near or over the central or southeastern coast of Louisiana tonight or Saturday, July 13 and then move inland over the Lower Mississippi Valley on Sunday, July 14.

Key Messages from the National Hurricane Center

— There is a danger of life-threatening storm surge inundation along the coast of southern and southeastern Louisiana where a Storm Surge Warning is in effect. The highest storm surge inundation is expected between Intracoastal City and Shell Beach. Residents in these areas should listen to any advice given by local officials.

— The slow movement of Barry will result in a long duration heavy rainfall and flood threat along the central Gulf Coast and inland through the lower Mississippi Valley through the weekend into early next week. Flash flooding and river flooding will become increasingly likely, some of which may be significant, especially along and east of the track of the system.

— Hurricane conditions are expected along a portion of the coast of Louisiana, where a Hurricane Warning has been issued. Residents in these areas should rush their preparations to completion, as tropical storm conditions are expected to arrive in the warning area by Friday morning.

Related article:

NASA Tracks Tropical Storm Barry in Gulf of Mexico

For updated forecasts, visit: https://www.nhc.noaa.gov

NASA’s Aqua satellite: https://www.nasa.gov/mission_pages/aqua/index.html

Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.chArchive link

Getting the most out of the Global25

The first thing you need to know about the Global25 is that I update the relevant datasheets regularly, usually every week or two, but they’re always at these links:

Global25 datasheet (scaled) Global25 pop averages (scaled) Global25 datasheet Global25 pop averages

Each sample has a population code and an individual code. The population codes represent the countries, ethnic groups and/or archeological affinities of the samples, and I often modify these codes to suit my needs. On the other hand, the individual codes are unique to most of the samples and I usually don’t change them. So if you’d like to know more details about the samples try searching for their individual codes via a decent online search engine. Basic information about many of the samples is also available in the «anno» files here. The main purpose of the Global25 is to provide data for mixture modeling. In other words, for estimating ancestry proportions, and in particular ancient ancestry proportions. This can be done on your computer with the R program and the nMonte R script, or online with the Global25 nMonte Runner, which I discuss below. If you don’t have R installed on your computer, you can get it here, while nMonte is available here. For this tutorial please download nMonte and nMonte3, and store them in your main working folder (usually My Documents). Once you have R set up, make sure its working directory is the same place where you stored nMonte. You can check this in R by clicking on «File» and then «Change dir». Additionally, you’ll need two nMonte input files in the working directory titled «data» and «target». Examples of these files are available here. We’ll be using them to test the ancient ancestry proportions of a sample set from present-day England. Before you can begin the analysis you need to first call the nMonte script by typing or copy pasting source(‘nMonte.R’) into the R console window, and then hitting «enter» on your keyboard. This is what you should see in the R console window afterwards.

To start the mixture modeling process, type or copy paste getMonte(‘data.txt’, ‘target.txt’) into the R console window, hit «enter», and wait for the results. After a short time, probably less than a minute or two, you should see this output.

The data and target files contain population averages, and, as you can see, the results that these population averages produced were in line with what one would expect from such a model focusing on the genetic shifts in Europe and surrounds during the Late Neolithic. Very similar ancient ancestry proportions have been reported for the English and other Northern Europeans recently in scientific literature. However, when focusing on exceptionally fine-scale genetic variation that isn’t reflected too well in the Global25 population averages, a more effective strategy might be to use multiple individuals from each reference population and let nMonte3 aggregate and average the inferred ancestry proportions. This is often the case when attempting to model ancestry proportions for more recent periods, such as the Middle Ages. So let’s try this with the English sample set using a modified data file, which is available here. Replace the old data file with the new one in your working directory, and, like before, copy paste into the R console window the following two commands, hitting «enter» after each one: source(‘nMonte3.R’) and getMonte(‘data.txt’, ‘target.txt’). This is what you should eventually see.

It’s difficult to say how accurate these estimates are. But they look more or less correct considering the limited and less than ideal reference samples. For instance, the individuals labeled SWE_Viking_Age_Sigtuna are supposed to be stand ins for Danish and Norwegian Vikings, but they’re a relatively heterogeneous group from Sweden, possibly with some British or Irish ancestry, so they might be skewing the results. However, I’ll be adding many more ancient samples to the Global25 datasheets as they become available, including lots of new Vikings, which should greatly improve the accuracy of these sorts of fine-scale mixture models. An alternative to the R-based approach is the online Global25 nMonte Runner [LINK]. This is a free tool, and easy to work with via several drop down menus, but users must become sponsors to unlock all of its available features. To run an analysis follow these three steps:

1) use the first drop down menu to pick the reference populations of your choice (up to four are allowed for free users) 2) move down to the second set of the drop down lists and either pick a test population that is already in the system or copy paste a set of Global25 coordinates into the space labeled «Enter/Paste Sets of Coordinates — Scaled and Comma-separated» 3) feel free to experiment with the additional options if you’re game and willing to part with a little cash to help pay for the site.

However, it’s important to note that the Global25 is a Principal Component Analysis (PCA), so it makes good sense to also use it for producing PCA graphs. To do this just plot any combination of two or three of its Principal Components (PCs) to create 2D or 3D graphs, respectively. This can be done with a wide variety of programs, including PAST, which is freely available here. To produce a 2D graph, open a Global25 datasheet in PAST, choose comma as the separator, highlight any two columns of data, click on the «Plot» tab and, from the drop down list, pick «XY graph». Below is a series of graphs that I created in exactly this way. I also color coded the samples according to their geographic origins. This was done by ticking the «Row attributes» tab.

PAST can also be used to run PCA on subsets of the Global25 scaled data to produce remarkably accurate plots of fine-scale population structure. To try this create a new text file with your choice of populations from the Global25 scaled datasheet, open it with PAST and choose Multivariate > Ordination > Principal Components Analysis. I’ve already put together several datasheets limited to European, Northern European, West Eurasian and South Asian populations. They’re available at the links below along with more details on how to run them with PAST.

Global25 workshop 1: that classic West Eurasian plot Global25 workshop 2: intra-European variation Global25 workshop 3: genes vs geography in Northern Europe The South Asian cline that no longer exists

And if you’re fond of tree-like structures as a means to describe fine-scale genetic variation, please check out this blog post…

Global25 workshop 4: a neighbour joining tree

Rocket Fuel in Her Blood: The Story of JoAnn Morgan

As the Apollo 11 mission lifted off on the Saturn V rocket, propelling humanity to the surface of the Moon for the very first time, members of the team inside Launch Control Center watched through a window.

The room was crowded with men in white shirts and dark ties, watching attentively as the rocket thrust into the sky. But among them sat one woman, seated to the left of center in the third row in the image below. In fact, this was the only woman in the launch firing room for the Apollo 11 liftoff.


This is JoAnn Morgan, the instrumentation controller for Apollo 11. Today, this is what Morgan is most known for. But her career at NASA spanned over 45 years, and she continued to break ceiling after ceiling for women involved with the space program.

“It was just meant to be for me to be in the launching business,” she says. “I’ve got rocket fuel in my blood.”


Morgan was inspired to join the human spaceflight program when Explorer 1 was launched into space in 1958, the first satellite to do so from the United States. Explorer 1 was instrumental in discovering what has become known as the Van Allen radiation belt. 

“I thought to myself, this is profound knowledge that concerns everyone on our planet,” she says. “This is an important discovery, and I want to be a part of this team. I was compelled to do it because of the new knowledge, the opportunity for new knowledge.”


The opportunity came when Morgan spotted an advertisement for two open positions with the Army Ballistic Missile Agency. The ad listed two Engineer’s Aide positions available for two students over the summer.

 “Thank God it said ‘students’ and not ‘boys’” says Morgan, “otherwise I wouldn’t have applied.”

After Morgan got the position, the program was quickly rolled into a brand-new space exploration agency called NASA. Dr. Kurt Debus, the first director of Kennedy Space Center (KSC), looked at Morgan’s coursework and provided Morgan with a pathway to certification. She was later certified as a Measurement and Instrumentation Engineer and a Data Systems Engineer.


There was a seemingly infinite amount of obstacles that Morgan was forced to overcome — everything from obscene phone calls at her station to needing a security guard to clear out the men’s only restroom.

“You have to realize that everywhere I went — if I went to a procedure review, if I went to a post-test critique, almost every single part of my daily work — I’d be the only woman in the room,” reflects Morgan. “I had a sense of loneliness in a way, but on the other side of that coin, I wanted to do the best job I could.”


To be the instrumentation controller in the launch room for the Apollo 11 liftoff was as huge as a deal as it sounds. For Morgan, to be present at that pivotal point in history was ground-breaking: “It was very validating. It absolutely made my career.”


Much like the Saturn V rocket, Morgan’s career took off. She was the first NASA woman to win a Sloan Fellowship, which she used to earn a Master of Science degree in management from Stanford University in California. When she returned to NASA, she became a divisions chief of the Computer Systems division.


From there, Morgan excelled in many other roles, including deputy of Expendable Launch Vehicles, director of Payload Projects Management and director of Safety and Mission Assurance. She was one of the last two people who verified the space shuttle was ready to launch and the first woman at KSC to serve in an executive position, associate director of the center.


To this day, Morgan is still one of the most decorated women at KSC. Her numerous awards and recognitions include an achievement award for her work during the activation of Apollo Launch Complex 39, four exceptional service medals and two outstanding leadership medals. In 1995, she was inducted into the Florida Women’s Hall of Fame.

After serving as the director of External Relations and Business Development, she retired from NASA in August 2003.


Today, people are reflecting on the 50th anniversary of Apollo 11, looking back on photos of the only woman in the launch firing room and remembering Morgan as an emblem of inspiration for women in STEM. However, Morgan’s takeaway message is to not look at those photos in admiration, but in determination to see those photos “depart from our culture.”

“I look at that picture of the firing room where I’m the only woman. And I hope all the pictures now that show people working on the missions to the Moon and onto Mars, in rooms like Mission Control or Launch Control or wherever — that there will always be several women. I hope that photos like the ones I’m in don’t exist anymore.”


Follow Women@NASA for more stories like this one, and make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Coral reefs shifting away from equator

Coral reefs are retreating from equatorial waters and establishing new reefs in more temperate regions, according to new research in the journal Marine Ecology Progress Series. The researchers found that the number of young corals on tropical reefs has declined by 85 percent — and doubled on subtropical reefs — during the last four decades.

Coral reefs shifting away from equator
Corals grow alongside seaweed in the temperate waters surrounding Nagasaki, Japan. Recent research shows
that corals are establishing new reefs in temperate regions as they retreat from increasingly warmer
waters at the equator [Credit: Soyoka Muko/Nagasaki University]

«Climate change seems to be redistributing coral reefs, the same way it is shifting many other marine species,» said Nichole Price, a senior research scientist at Bigelow Laboratory for Ocean Sciences and lead author of the paper. «The clarity in this trend is stunning, but we don’t yet know whether the new reefs can support the incredible diversity of tropical systems.»

As climate change warms the ocean, subtropical environments are becoming more favorable for corals than the equatorial waters where they traditionally thrived. This is allowing drifting coral larvae to settle and grow in new regions. These subtropical reefs could provide refuge for other species challenged by climate change and new opportunities to protect these fledgling ecosystems.

The researchers believe that only certain types of coral are able to reach these new locations, based on how far the microscopic larvae can swim and drift on currents before they run out of their limited fat stores. The exact composition of most new reefs is currently unknown, due to the expense of collecting genetic and species diversity data.

«We are seeing ecosystems transition to new blends of species that have never coexisted, and it’s not yet clear how long it takes for these systems to reach equilibrium,» said Satoshi Mitarai, an associate professor at Okinawa Institute of Science and Technology Graduate University and an author of the study. «The lines are really starting to blur about what a native species is, and when ecosystems are functioning or falling apart.»

New coral reefs grow when larvae settle on suitable seafloor away from the reef where they originated. The research team examined latitudes up to 35 degrees north and south of the equator, and found that the shift of coral reefs is perfectly mirrored on either side. The paper assesses where and when «refugee corals» could settle in the future — potentially bringing new resources and opportunities such as fishing and tourism.

Coral reefs shifting away from equator
An experiment in Palmyra Atoll National Wildlife Refuge collects coral larvae, allowing researchers to enumerate
the number of baby corals settling on a reef. Recent research shows that corals are establishing new reefs
 in temperate regions as they retreat from increasingly warmer waters at the equator
[Credit: Nichole Price/Bigelow Laboratory for Ocean Sciences]

The researchers, an international group from 17 institutions in 6 countries, compiled a global database of studies dating back to 1974, when record-keeping began. They hope that other scientists will add to the database, making it increasingly comprehensive and useful to other research questions.

«The results of this paper highlight the importance of truly long-term studies documenting change in coral reef communities,» said Peter Edmunds, a professor at the University of California Northridge and author of the paper. «The trends we identified in this analysis are exceptionally difficult to detect, yet of the greatest importance in understanding how reefs will change in the coming decades. As the coral reef crisis deepens, the international community will need to intensify efforts to combine and synthesize results as we have been able to accomplish with this study.»

Coral reefs are intricately interconnected systems, and it is the interplay between species that enables their healthy functioning. It is unclear which other species, such as coralline algae that facilitate the survival of vulnerable coral larvae, are also expanding into new areas ¬- or how successful young corals can be without them. Price wants to investigate the relationships and diversity of species in new reefs to understand the dynamics of these evolving ecosystems.

«So many questions remain about which species are and are not making it to these new locations, and we don’t yet know the fate of these young corals over longer time frames,» Price said. «The changes we are seeing in coral reef ecosystems are mind-boggling, and we need to work hard to document how these systems work and learn what we can do to save them before it’s too late.»

Some of the research that informed this study was conducted at the National Science Foundation’s Moorea Coral Reef Long-Term Ecological Research site near French Polynesia, one of 28 such long-term research sites across the country and around the globe.

«This report addresses the important question of whether warming waters have resulted in increases in coral populations,» says David Garrison, a program director in the National Science Foundation’s Division of Ocean Sciences, which funded the research. «Whether this offers hope for the sustainability of coral reefs requires more research and monitoring.»

Source: Bigelow Laboratory for Ocean Sciences [July 09, 2019]




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