пятница, 13 июля 2018 г.

Cheesed-off Cholera Cholera bacteria are very happy in the…

Cheesed-off Cholera

Cholera bacteria are very happy in the human small intestine. They proliferate wildly, spew out toxins and have a merry old time at the host’s expense. Indeed, the severe diarrhoea caused by the bugs kills up to 143,000 people each year. But, if Lactococcus lactis – a harmless bacterium found in cheese – gets to the intestine first, they can ruin the party for cholera. L. lactis colonies (top row) produce lactic acid (yellow) that suppresses the growth of cholera colonies (bottom row) – the middle L. lactis colony is a mutant unable to produce the acid. In mice, it’s been shown that swallowing L. lactis together with cholera bacteria improved the animals’ chances of survival. While eating cheese is probably insufficient to fend off cholera in people, if these results do translate to humans, it suggests that using L. lactis as a probiotic might compliment existing cholera prevention measures and treatments.

Written by Ruth Williams

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HiPOD (13 July 2018): Lava-Coated Craters   – The larger crater…

HiPOD (13 July 2018): Lava-Coated Craters

   – The larger crater looks normal–dimpled depression with a protruding rim barely covered by lava which later deflated. The smaller depression looks deeper and steeper-sided, and the rim does not protrude, so it is probably below the level of even the deflated lava. So why did this deflate so much?

NASA/JP/University of Arizona (276 km above the surface, less than 5 km across)


2018 July 13 Star Trails and the Bracewell Radio Sundial Image…

2018 July 13

Star Trails and the Bracewell Radio Sundial
Image Credit & Copyright: Miles Lucas at NRAO

Explanation: Sundials use the location of a shadow to measure the Earth’s rotation and indicate the time of day. So it’s fitting that this sundial, at the Very Large Array Radio Telescope Observatory in New Mexico, commemorates the history of radio astronomy and radio astronomy pioneer Ronald Bracewell. The radio sundial was constructed using pieces of a solar mapping radio telescope array that Bracewell orginaly built near the Stanford University campus. Bracewell’s array was used to contribute data to plan the first Moon landing, its pillars signed by visiting scientists and radio astronomers, including two Nobel prize winners. As for most sundials the shadow cast by the central gnomon follows markers that show the solar time of day, along with solstices and equinoxes. But markers on the radio sundial are also laid out according to local sidereal time. They show the position of the invisible radio shadows of three bright radio sources in Earth’s sky, supernova remnant Cassiopeia A, active galaxy Cygnus A, and active galaxy Centaurus A. Sidereal time is just star time, the Earth’s rotation as measured with the stars and distant galaxies. That rotation is reflected in this composited hour-long exposure. Above the Bracewell Radio Sundial, the stars trace concentric trails around the north celestial pole.

∞ Source: apod.nasa.gov/apod/ap180713.html


“Pleasure” flights in the space planned from 2019

Virgin Galactic logo / Blue Origin logo.

July 13, 2018

Pioneering companies in the field of space tourism claim to be able to offer flights in just a few months. Virgin Galactic and Blue Origin are racing to be the first to finish the tests.

SpaceShipTwo VSS Unity attached under a carrier plane, WhiteKnightTwo

The two most advanced private companies in the space tourism market say they are only a few months away from their first flights into space with customers on board, although each remains cautious and refrains from advancing a specific date.

Blue Origin New Shepard rocket launch

Virgin Galactic, founded by British billionaire Richard Branson, and Blue Origin, by the more discreet billionaire Jeff Bezos, boss of Amazon, are racing to be the first to finish the tests. Both companies have radically different technologies.

Few minutes of weightlessness

For both, the passengers will not go into orbit around the Earth: their experience in weightlessness will only last a few minutes, unlike the few space tourists who paid tens of millions of dollars to travel aboard a Soyuz and of the International Space Station (ISS) in the 2000s.

For a ticket much cheaper (250 000 dollars at Virgin, an amount unknown at Blue Origin), these new tourists will be propelled to several tens of kilometers, before falling back to Earth. By comparison, the ISS is in orbit at 400 km.

The goal is to approach or exceed the imaginary line marking the beginning of space, the Karman line, 100 km, or the line preferred by the US military, 50 miles (80 km). At this altitude, the sky becomes darker, and the curvature of the Earth appears clearly.

Virgin Galactic

At Virgin Galactic, six passengers and two pilots will set up aboard the SpaceShipTwo VSS Unity, which looks like a private jet. The VSS Unity will be attached under a carrier plane, dubbed WhiteKnightTwo. Once dropped at an altitude of 15,000 meters, the ship will light its rocket towards the sky. There passengers will float in weightlessness for several minutes.

The descent will be slowed down by a system of “empennage”: the fins of the tail of the ship will pivot and the ship will arch before returning to normal. Then the aircraft will land on an airstrip from Virgin’s “spaceport” in the New Mexico desert.

SpaceShipTwo VSS Unity

In a May 29 test in the Mojave desert, the ship reached an altitude of 35 km. In October 2014, Virgin’s ship crashed into flight due to a pilot error, killing one of the two pilots. The tests resumed with a new device.

Virgin has reached an agreement to open a second spaceport in Italy, at Taranto-Grottaglie airport. Richard Branson said in May, on BBC Radio 4, he hoped to be one of the first passengers in the next 12 months. About 650 customers are on the waiting list, says Virgin to AFP.

Blue Origin

Blue Origin has developed a system that resembles traditional rockets: the New Shepard. Six passengers will sit in the seats of a “capsule”, a cabin attached to the top of a vertical rocket 18 meters in height. After the launch, which will propel the capsule to near Mach 3, it will detach and continue its trajectory a few kilometers to the sky. In a test on April 29, the capsule reached 107 km. During this time, the rocket will come down again … and will land, slowly, vertically.

Blue Origin Crew Capsule

After several minutes of weightlessness, during which passengers can get up and look out through large portholes, the capsule will fall back to Earth, slowed by three large parachutes and retrofuses. From take-off to landing, the flight of the last test lasted 10 minutes.

So far only manikin testing has been done on the Blue Origin site in Texas. But a leader, Rob Meyerson, said in June that the first inhabited tests would take place “soon”. Another official, Yu Matsutomi, said Wednesday at a conference that they would be held “at the end of this year,” according to Space News.

And after?

SpaceX and Boeing are developing capsules to transport NASA astronauts, probably from 2020 as a result of delays. Considerable investments that these companies will probably seek to amortize by offering trips to individuals.

Boeing and SpaceX Crew Vehicles

“If you want to go into space, you’ll soon have four times more options than you’ve ever had,” says AFP Phil Larson, deputy dean of the School of Engineering of the United States. University of Colorado at Boulder.

In the longer term, the Russian company building the Soyuz is studying the possibility of bringing tourists back to the ISS. And an American start-up, Orion Span, has announced this year to place a space station in orbit in a few years, but this project is still very far from the day.

Related links:

Virgin Galactic: http://www.virgingalactic.com/

Blue Origin: https://www.blueorigin.com/

Images, Text, Credits: Virgin Galactic/Blue Origin/Boeing/SpaceX/AFP/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.chArchive link


NASA’s Fermi Traces Source of Cosmic Neutrino to Monster Black Hole

NASA – Fermi Gamma-ray Space Telescope logo.

July 12, 2018

For the first time ever, scientists using NASA’s Fermi Gamma-ray Space Telescope have found the source of a high-energy neutrino from outside our galaxy. This neutrino traveled 3.7 billion years at almost the speed of light before being detected on Earth. This is farther than any other neutrino whose origin scientists can identify.

High-energy neutrinos are hard-to-catch particles that scientists think are created by the most powerful events in the cosmos, such as galaxy mergers and material falling onto supermassive black holes. They travel at speeds just shy of the speed of light and rarely interact with other matter, allowing them to travel unimpeded across distances of billions of light-years.

Image above: NASA’s Fermi (top left) has achieved a new first—identifying a monster black hole in a far-off galaxy as the source of a high-energy neutrino seen by the IceCube Neutrino Observatory (sensor strings, bottom). Image Credits: NASA/Fermi and Aurore Simonnet, Sonoma State University.

The neutrino was discovered by an international team of scientists using the National Science Foundation’s IceCube Neutrino Observatory at the Amundsen–Scott South Pole Station. Fermi found the source of the neutrino by tracing its path back to a blast of gamma-ray light from a distant supermassive black hole in the constellation Orion.

“Again, Fermi has helped make another giant leap in a growing field we call multimessenger astronomy,” said Paul Hertz, director of the Astrophysics Division at NASA Headquarters in Washington. “Neutrinos and gravitational waves deliver new kinds of information about the most extreme environments in the universe. But to best understand what they’re telling us, we need to connect them to the ‘messenger’ astronomers know best—light.”

Scientists study neutrinos, as well as cosmic rays and gamma rays, to understand what is going on in turbulent cosmic environments such as supernovas, black holes and stars. Neutrinos show the complex processes that occur inside the environment, and cosmic rays show the force and speed of violent activity. But, scientists rely on gamma rays, the most energetic form of light, to brightly flag what cosmic source is producing these neutrinos and cosmic rays.

“The most extreme cosmic explosions produce gravitational waves, and the most extreme cosmic accelerators produce high-energy neutrinos and cosmic rays,” says Regina Caputo of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the analysis coordinator for the Fermi Large Area Telescope Collaboration. “Through Fermi, gamma rays are providing a bridge to each of these new cosmic signals.”

The discovery is the subject of two papers published Thursday in the journal Science. The source identification paper also includes important follow-up observations by the Major Atmospheric Gamma Imaging Cherenkov Telescopes and additional data from NASA’s Neil Gehrels Swift Observatory and many other facilities.

Image above: The discovery of a high-energy neutrino on September 22, 2017, sent astronomers on a chase to locate its source—a supermassive black hole in a distant galaxy. Image Credits: NASA’s Goddard Space Flight Center.

On Sept. 22, 2017, scientists using IceCube detected signs of a neutrino striking the Antarctic ice with energy of about 300 trillion electron volts—more than 45 times the energy achievable in the most powerful particle accelerator on Earth. This high energy strongly suggested that the neutrino had to be from beyond our solar system. Backtracking the path through IceCube indicated where in the sky the neutrino came from, and automated alerts notified astronomers around the globe to search this region for flares or outbursts that could be associated with the event.

Data from Fermi’s Large Area Telescope revealed enhanced gamma-ray emission from a well-known active galaxy at the time the neutrino arrived. This is a type of active galaxy called a blazar, with a supermassive black hole with millions to billions of times the Sun’s mass that blasts jets of particles outward in opposite directions at nearly the speed of light. Blazars are especially bright and active because one of these jets happens to point almost directly toward Earth.

Image above: Fermi-detected gamma rays from TXS 0506+056 are shown as expanding circles. Their maximum size, color—from white (low) to magenta (high)—and associated tone indicate the energy of each ray. Image Credits: NASA/DOE/Fermi LAT Collab.

Fermi scientist Yasuyuki Tanaka at Hiroshima University in Japan was the first to associate the neutrino event with the blazar designated TXS 0506+056 (TXS 0506 for short).

“Fermi’s LAT monitors the entire sky in gamma rays and keeps tabs on the activity of some 2,000 blazars, yet TXS 0506 really stood out,” said Sara Buson, a NASA Postdoctoral Fellow at Goddard who performed the data analysis with Anna Franckowiak, a scientist at the Deutsches Elektronen-Synchrotron research center in Zeuthen, Germany. “This blazar is located near the center of the sky position determined by IceCube and, at the time of the neutrino detection, was the most active Fermi had seen it in a decade.”

Visualizing Gamma Rays From Blazar TXS 0506+056

Video above: Fermi-detected gamma rays from TXS 0506+056 are shown as expanding circles. Their maximum size, color—from white (low) to magenta (high)—and associated tone indicate the energy of each ray. The first sequence shows typical emission; the second shows the 2017 flare leading to the neutrino detection. Video Credits: NASA/DOE/Fermi LAT Collab., Matt Russo and Andrew Santaguida/SYSTEM Sounds.

NASA’s Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States. The NASA Postdoctoral Fellow program is administered by Universities Space Research Association under contract with NASA.

For more about NASA’s Fermi mission, visit: https://www.nasa.gov/fermi

Fermi Gamma-Ray Space Telescope: http://www.nasa.gov/mission_pages/GLAST/main/index.html

Related links:

The source identification paper: http://science.sciencemag.org/cgi/doi/10.1126/science.aat1378

Major Atmospheric Gamma Imaging Cherenkov Telescopes: https://magic.mpp.mpg.de/

NASA’s Neil Gehrels Swift Observatory: https://www.nasa.gov/mission_pages/swift/main

Deutsches Elektronen-Synchrotron: http://www.desy.de/index_eng.html

Images (mentioned), Video (mentioned), Text, Credits: NASA/Felicia Chou/Sean Potter/GSFC/Dewayne Washington.

Greetings, Orbiter.chArchive link


Observatories Team Up to Reveal Rare Double Asteroid

Asteroid Watch logo.

July 12, 2018

New observations by three of the world‘s largest radio telescopes have revealed that an asteroid discovered last year is actually two objects, each about 3,000 feet (900 meters) in size, orbiting each other.

Rare Double Asteroid Revealed by NASA, Observatories

Video above: Three of the world’s largest radio telescopes team up to show a rare double asteroid. 2017 YE5 is only the fourth binary near-Earth asteroid ever observed in which the two bodies are roughly the same size, and not touching. This video shows radar images of the pair gathered by Goldstone Solar System Radar, Arecibo Observatory and Green Bank Observatory. Video Credits: NASA/JPL-Caltech.

Near-Earth asteroid 2017 YE5 was discovered with observations provided by the Morocco Oukaimeden Sky Survey on Dec. 21, 2017, but no details about the asteroid’s physical properties were known until the end of June. This is only the fourth “equal mass” binary near-Earth asteroid ever detected, consisting of two objects nearly identical in size, orbiting each other. The new observations provide the most detailed images ever obtained of this type of binary asteroid.

On June 21, the asteroid 2017 YE5 made its closest approach to Earth for at least the next 170 years, coming to within 3.7 million miles (6 million kilometers) of Earth, or about 16 times the distance between Earth and the Moon. On June 21 and 22, observations by NASA’s Goldstone Solar System Radar (GSSR) in California showed the first signs that 2017 YE5 could be a binary system. The observations revealed two distinct lobes, but the asteroid’s orientation was such that scientists could not see if the two bodies were separate or joined. Eventually, the two objects rotated to expose a distinct gap between them.

Animation above: Bi-static radar images of the binary asteroid 2017 YE5 from the Arecibo Observatory and the Green Bank Observatory on June 25. The observations show that the asteroid consists of two separate objects in orbit around each other. Animation Credits: Arecibo/GBO/NSF/NASA/JPL-Caltech.

Scientists at the Arecibo Observatory in Puerto Rico had already planned to observe 2017 YE5, and they were alerted by their colleagues at Goldstone of the asteroid’s unique properties. On June 24, the scientists teamed up with researchers at the Green Bank Observatory (GBO) in West Virginia and used the two observatories together in a bi-static radar configuration (in which Arecibo transmits the radar signal and Green Bank receives the return signal). Together, they were able to confirm that 2017 YE5 consists of two separated objects. By June 26, both Goldstone and Arecibo had independently confirmed the asteroid’s binary nature.

The new observations obtained between June 21 and 26 indicate that the two objects revolve around each other once every 20 to 24 hours. This was confirmed with visible-light observations of brightness variations by Brian Warner at the Center for Solar System Studies in Rancho Cucamonga, California.

Anamation above: Radar images of the binary asteroid 2017 YE5 from NASA’s Goldstone Solar System Radar (GSSR). The observations, conducted on June 23, 2018, show two lobes, but do not yet show two separate objects. Animation Credits: GSSR/NASA/JPL-Caltech.

Radar imaging shows that the two objects are larger than their combined optical brightness originally suggested, indicating that the two rocks do not reflect as much sunlight as a typical rocky asteroid. 2017 YE5 is likely as dark as charcoal. The Goldstone images taken on June 21 also show a striking difference in the radar reflectivity of the two objects, a phenomenon not seen previously among more than 50 other binary asteroid systems studied by radar since 2000. (However, the majority of those binary asteroids consist of one large object and a much smaller satellite.) The reflectivity differences also appear in the Arecibo images and hint that the two objects may have different densities, compositions near their surfaces, or different surface roughnesses.

Animation above: Artist’s concept of what binary asteroid 2017 YE5 might look like. The two objects showed striking differences in radar reflectivity, which could indicate that they have different surface properties. Animation Credits: NASA/JPL-Caltech.

Scientists estimate that among near-Earth asteroids larger than 650 feet (200 meters) in size, about 15 percent are binaries with one larger object and a much smaller satellite. Equal-mass binaries like 2017 YE5 are much rarer. Contact binaries, in which two similarly sized objects are in contact, are thought to make up another 15 percent of near-Earth asteroids larger than 650 feet (200 meters) in size.

Animation above: Artist’s illustration of the trajectory of asteroid 2017 YE5 through the solar system. At its closest approach to Earth, the asteroid came to within 16 times the distance between Earth and the moon. Animation Credits: NASA/JPL-Caltech.

The discovery of the binary nature of 2017 YE5 provides scientists with an important opportunity to improve understanding of different types of binaries and to study the formation mechanisms between binaries and contact binaries, which may be related. Analysis of the combined radar and optical observations may allow scientists to estimate the densities of the 2017 YE5 objects, which will improve understanding of their composition and internal structure, and of how they formed.

Study contributors

The Goldstone observations were led by Marina Brozović, a radar scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California.

Anne Virkki, Flaviane Venditti and Sean Marshall of the Arecibo Observatory and the University of Central Florida led the observations using the Arecibo Observatory.

Patrick Taylor of the Universities Space Research Association (USRA), scientist at the Lunar and Planetary Institute, led the bi-static radar observations with GBO, home of the Green Bank Telescope (GBT), the world’s largest fully steerable radio telescope.

Image above: This optical composite image shows asteroid 2017 YE5, taken on June 30, 2018, by the Cadi Ayyad University Morocco Oukaimeden Sky Survey, one of the first surveys to identify 2017 YE5 in December 2017. Image Credits: Cadi Ayyad University Morocco Oukaimeden Sky Survey.

The Arecibo, Goldstone and USRA planetary radar projects are funded through NASA’s Near-Earth Object Observations Program within the Planetary Defense Coordination Office (PDCO), which manages the Agency’s Planetary Defense Program. The Arecibo Observatory is a facility of the National Science Foundation operated under cooperative agreement by the University of Central Florida, Yang Enterprises, and Universidad Metropolitana. GBO is a facility of the National Science Foundation, operated under a cooperative agreement by Associated Universities, Inc.

In addition to the resources NASA puts into understanding asteroids, the PDCO also partners with other U.S. government agencies, university-based astronomers, and space science institutes across the country, often with grants, interagency transfers and other contracts from NASA. They also collaborate with international space agencies and institutions that are working to track and better understand these smaller objects of the Solar System. In addition, NASA values the work of numerous highly skilled amateur astronomers, whose accurate observational data helps improve asteroid orbits after discovery.

More information about asteroids and near-Earth objects is at these sites:



Asteroids: https://www.nasa.gov/mission_pages/asteroids/main/index.html

Images (mentioned), Animation (mentioned), Video (mentioned), Text, Credits: NASA/JoAnna Wendel/Tony Greicius/JPL/Calla Cofield.

Greetings, Orbiter.chArchive link


Hubble and Gaia Team Up to Fuel Cosmic Conundrum

Using two of the world’s most powerful space telescopes — NASA’s Hubble and ESA’s Gaia — astronomers have made the most precise measurements to date of the universe’s expansion rate. This is calculated by gauging the distances between nearby galaxies using special types of stars called Cepheid variables as cosmic yardsticks. By comparing their intrinsic brightness as measured by Hubble, with their apparent brightness as seen from Earth, scientists can calculate their distances. Gaia further refines this yardstick by geometrically measuring the distances to Cepheid variables within our Milky Way galaxy. This allowed astronomers to more precisely calibrate the distances to Cepheids that are seen in outside galaxies.  Science: NASA, ESA, and A. Riess (STScI/JHU)

Using the power and synergy of two space telescopes, astronomers have made the most precise measurement to date of the universe’s expansion rate.

The results further fuel the mismatch between measurements for the expansion rate of the nearby universe, and those of the distant, primeval universe — before stars and galaxies even existed.

This so-called “tension” implies that there could be new physics underlying the foundations of the universe. Possibilities include the interaction strength of dark matter, dark energy being even more exotic than previously thought, or an unknown new particle in the tapestry of space.

Combining observations from NASA’s Hubble Space Telescope and the European Space Agency’s (ESA) Gaia space observatory, astronomers further refined the previous value for the Hubble constant, the rate at which the universe is expanding from the big bang 13.8 billion years ago.

But as the measurements have become more precise, the team’s determination of the Hubble constant has become more and more at odds with the measurements from another space observatory, ESA’s Planck mission, which is coming up with a different predicted value for the Hubble constant.

Planck mapped the primeval universe as it appeared only 360,000 years after the big bang. The entire sky is imprinted with the signature of the big bang encoded in microwaves. Planck measured the sizes of the ripples in this Cosmic Microwave Background (CMB) that were produced by slight irregularities in the big bang fireball. The fine details of these ripples encode how much dark matter and normal matter there is, the trajectory of the universe at that time, and other cosmological parameters.

These measurements, still being assessed, allow scientists to predict how the early universe would likely have evolved into the expansion rate we can measure today. However, those predictions don’t seem to match the new measurements of our nearby contemporary universe.

“With the addition of this new Gaia and Hubble Space Telescope data, we now have a serious tension with the Cosmic Microwave Background data,” said Planck team member and lead analyst George Efstathiou of the Kavli Institute for Cosmology in Cambridge, England, who was not involved with the new work.

“The tension seems to have grown into a full-blown incompatibility between our views of the early and late time universe,” said team leader and Nobel Laureate Adam Riess of the Space Telescope Science Institute and the Johns Hopkins University in Baltimore, Maryland. “At this point, clearly it’s not simply some gross error in any one measurement. It’s as though you predicted how tall a child would become from a growth chart and then found the adult he or she became greatly exceeded the prediction. We are very perplexed.”

In 2005, Riess and members of the SHOES (Supernova H0 for the Equation of State) Team set out to measure the universe’s expansion rate with unprecedented accuracy. In the following years, by refining their techniques, this team shaved down the rate measurement’s uncertainty to unprecedented levels. Now, with the power of Hubble and Gaia combined, they have reduced that uncertainty to just 2.2 percent.

Because the Hubble constant is needed to estimate the age of the universe, the long-sought answer is one of the most important numbers in cosmology. It is named after astronomer Edwin Hubble, who nearly a century ago discovered that the universe was uniformly expanding in all directions—a finding that gave birth to modern cosmology.

Galaxies appear to recede from Earth proportional to their distances, meaning that the farther away they are, the faster they appear to be moving away. This is a consequence of expanding space, and not a value of true space velocity. By measuring the value of the Hubble constant over time, astronomers can construct a picture of our cosmic evolution, infer the make-up of the universe, and uncover clues concerning its ultimate fate.

The two major methods of measuring this number give incompatible results. One method is direct, building a cosmic “distance ladder” from measurements of stars in our local universe. The other method uses the CMB to measure the trajectory of the universe shortly after the Big Bang and then uses physics to describe the universe and extrapolate to the present expansion rate. Together, the measurements should provide an end-to-end test of our basic understanding of the so-called “Standard Model” of the universe. However, the pieces don’t fit

Using Hubble and newly released data from Gaia, Riess’ team measured the present rate of expansion to be 73.5 kilometers (45.6 miles) per second per megaparsec. This means that for every 3.3 million light-years farther away a galaxy is from us, it appears to be moving 73.5 kilometers per second faster. However, the Planck results predict the universe should be expanding today at only 67.0 kilometers (41.6 miles) per second per megaparsec. As the teams’ measurements have become more and more precise, the chasm between them has continued to widen, and is now about 4 times the size of their combined uncertainty.

Over the years, Riess’ team has refined the Hubble constant value by streamlining and strengthening the “cosmic distance ladder,” used to measure precise distances to nearby and far-off galaxies. They compared those distances with the expansion of space, measured by the stretching of light from nearby galaxies. Using the apparent outward velocity at each distance, they then calculated the Hubble constant.

To gauge the distances between nearby galaxies, his team used a special type of star as cosmic yardsticks or milepost markers. These pulsating stars, called Cepheid variables, brighten and dim at rates that correspond to their intrinsic brightness. By comparing their intrinsic brightness with their apparent brightness as seen from Earth, scientists can calculate their distances.

Gaia further refined this yardstick by geometrically measuring the distance to 50 Cepheid variables in the Milky Way. These measurements were combined with precise measurements of their brightnesses from Hubble. This allowed the astronomers to more accurately calibrate the Cepheids and then use those seen outside the Milky Way as milepost markers.

“When you use Cepheids, you need both distance and brightness,” explained Riess. Hubble provided the information on brightness, and Gaia provided the parallax information needed to accurately determine the distances. Parallax is the apparent change in an object’s position due to a shift in the observer’s point of view. Ancient Greeks first used this technique to measure the distance from Earth to the Moon.

“Hubble is really amazing as a general-purpose observatory, but Gaia is the new gold standard for calibrating distance. It is purpose-built for measuring parallax—this is what it was designed to do,” Stefano Casertano of Space Telescope Science Institute and a member of the SHOES Team added. “Gaia brings a new ability to recalibrate all past distance measures, and it seems to confirm our previous work. We get the same answer for the Hubble constant if we replace all previous calibrations of the distance ladder with just the Gaia parallaxes. It’s a crosscheck between two very powerful and precise observatories.”

The goal of Riess’ team is to work with Gaia to cross the threshold of refining the Hubble constant to a value of only one percent by the early 2020s. Meanwhile, astrophysicists will likely continue to grapple with revisiting their ideas about the physics of the early universe.

The Riess team’s latest results are published in the July 12 issue of the Astrophysical Journal.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C.

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Ann Jenkins / Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4488 / 410-338-4514

jenkins@stsci.edu/ villard@stsci.edu

Adam Riess
Space Telescope Science Institute, Baltimore, Maryland


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Cancer, Fertility Research and Cargo Work Fill Crew Schedule

ISS – Expedition 56 Mission patch.

July 12, 2018

The Expedition 56 crew members explored a variety of microgravity science today potentially improving the lives of people on Earth and astronauts in space. The orbital residents are also unpacking a new resupply ship and getting ready for the departure of another.

Image above: NASA astronaut Ricky Arnold is inside the seven-windowed Cupola that provides views of the Earth below as well as approaching and departing resupply ships. Image Credit: NASA.

Cancer research is taking place aboard the International Space Station possibly leading to safer, more effective therapies. Flight Engineer Serena Auñón-Chancellor contributed to that research today by examining endothelial cells through a microscope for the AngieX Cancer Therapy study. AngieX is seeking a better model in space to test a treatment that targets tumor cells and blood vessels.

She also teamed up with Commander Drew Feustel imaging biological samples in a microscope for the Micro-11 fertility study. The experiment is researching whether successful reproduction is possible off the Earth.

The Northrop Grumman Cygnus space freighter has been packed full of trash and is due to leave the space station Sunday morning. Flight Engineer Alexander Gerst will command the Canadarm2 robotic arm to release Cygnus at 8:35 a.m. EDT as Auñón-Chancellor backs him up.  It will orbit Earth until July 30 for engineering studies before burning up harmlessly over the Pacific Ocean.

Image above: Sunset over South Pacific Ocean, seen by EarthCam on ISS, speed: 27’574 Km/h, altitude: 420,90 Km, image captured by Roland Berga (on Earth in Switzerland) from International Space Station (ISS) using ISS-HD Live application with EarthCam’s from ISS on July 12, 2018 at 21:44 UTC. Image Credits: Orbiter.ch Aerospace/Roland Berga.

Cosmonauts Oleg Artemyev and Sergey Prokopyev were back at work unpacking cargo delivered Monday aboard the new Progress 70 cargo craft. The 70P will stay at the station’s Pirs docking compartment until January.

Related links:

AngieX Cancer Therapy: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7502

Micro-11: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1922

Cygnus space freighter: https://www.nasa.gov/mission_pages/station/structure/launch/northrop-grumman.html

Progress 70 cargo craft: https://go.nasa.gov/2NDGreX

Expedition 56: https://cms.nasa.gov/mission_pages/station/expeditions/expedition56/index.html

Spot the Station: https://spotthestation.nasa.gov/

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Text, Credits: NASA/Mark Garcia/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.chArchive link


Multi-messenger astronomy

ESA – INTEGRAL Mission patch.

12 July 2018

An international team of scientists has found first evidence of a source of high-energy neutrinos: a flaring active galaxy, or blazar, 4 billion light years from Earth. Following a detection by the IceCube Neutrino Observatory on 22 September 2017, ESA’s INTEGRAL satellite joined a collaboration of observatories in space and on the ground that kept an eye on the neutrino source, heralding the thrilling future of multi-messenger astronomy.

Neutrinos are nearly massless, ‘ghostly’ particles that travel essentially unhindered through space at close to the speed of light [1]. Despite being some of the most abundant particles in the Universe – 100 000 billion pass through our bodies every second – these electrically neutral, subatomic particles are notoriously difficult to detect because they interact with matter incredibly rarely.

Image above: Artist’s impression of blazar neutrinos and gamma rays reaching Earth. Image Credits: IceCube/NASA.

While primordial neutrinos were created during the Big Bang, more of these elusive particles are routinely produced in nuclear reactions across the cosmos. The majority of neutrinos arriving at Earth derive from the Sun, but those that reach us with the highest energies are thought to stem from the same sources as cosmic rays – highly energetic particles originating from exotic sources outside the Solar System.

Unlike neutrinos, cosmic rays are charged particles and so their path is bent by magnetic fields, even weak ones. The neutral charge of neutrinos instead means they are unaffected by magnetic fields, and because they pass almost entirely through matter they can be used to trace a straight path all the way back to their source.

Acting as ‘messengers’, neutrinos directly carry astronomical information from the far reaches of the Universe. Over the past decades, several instruments have been built on Earth and in space to decode their messages, though detecting these particles is no easy feat. In particular, the source of high-energy neutrinos has, until now, remained unproven.

On 22 September 2017, one of these high-energy neutrinos arrived at the IceCube Neutrino Observatory at the South Pole [2]. The event was named IceCube-170922A.

The IceCube observatory, which encompasses a cubic kilometre of deep, pristine ice, detects neutrinos through their secondary particles, muons. These muons are produced on the rare occasion that a neutrino interacts with matter in the vicinity of the detector, and they create tracks, kilometres in length, as they pass through layers of Antarctic ice. Their long paths mean their position can be well defined, and the source of the parent neutrino can be pinned down in the sky.

During the 22 September event, a traversing muon deposited 22 TeV of energy in the IceCube detector. From this, scientists estimated the energy of the parent neutrino to be around 290 TeV, indicating a 50 percent chance that it had an astrophysical origin beyond the Solar System.

Image above: Neutrino detection at the IceCube observatory. Image Credits: IceCube Collaboration/NSF.

When the origin of a neutrino cannot be robustly identified by IceCube, like in this case, multi-wavelength observations are required to investigate its source. So, following the detection, IceCube scientists circulated the coordinates in the sky of the neutrino’s origin, inferred from their observations, to a worldwide network of ground and space-based observatories working across the full electromagnetic spectrum.

These included NASA’s Fermi gamma-ray space telescope and the Major Atmospheric Gamma-Ray Imaging Cherenkov (MAGIC) on La Palma, in the Canary Islands, which looked to this portion of the sky and found the known blazar, TXS 0506+056, in a ‘flaring’ state – a period of intense high-energy emission – at the same time the neutrino was detected at the South Pole.

Blazars are the central cores of giant galaxies that host an actively accreting supermassive black-hole at their heart, where matter spiralling in forms a hot, rotating disc that generates enormous amounts of energy, along with a pair of relativistic jets.

These jets are colossal columns that funnel radiation, photons and particles – including neutrinos and cosmic rays – tens of light years away from the central black hole at speeds very close to the speed of light. A specific feature of blazars is that one of these jets happens to point towards Earth, making its emission appear exceptionally bright.

Scientists around the world began observing this blazar – the likely source of the neutrino detected by IceCube – in a variety of wavelengths, from radio waves to high-energy gamma rays. ESA’s INTEGRAL gamma-ray observatory was part of this international collaboration [3].

“This is a very important milestone to understanding how high-energy neutrinos are produced,” says Carlo Ferrigno from the INTEGRAL Science Data Centre at the University of Geneva, Switzerland.

“There have been previous claims that blazar flares were associated with the production of neutrinos, but this, the first confirmation, is absolutely fundamental. This is an exciting period for astrophysics,” he adds.

INTEGRAL, which surveys the sky in hard X-rays and soft gamma rays, is also sensitive to transient high-energy sources across the whole sky. At the time the neutrino was detected, it did not record any burst of gamma rays from the location of the blazar, so scientists were able to rule out prompt emissions from certain sources, such as a gamma-ray burst.

Image above: Artist’s impression of INTEGRAL. Image Credit: ESA.

After the neutrino alert from IceCube, INTEGRAL pointed to this area of the sky on various occasions between 30 September and 24 October 2017 with its wide-field instruments, and it did not observe the blazar to be in a flaring state in the hard X-ray or soft gamma-ray range.

The fact that INTEGRAL could not detect the source in the follow-up observations provided significant information about this blazar, allowing scientists to place a useful upper limit on its energy output during this period.

“INTEGRAL was important in constraining the properties of this blazar, but also in allowing scientists to exclude other neutrino sources such as gamma-ray bursts,” explains Volodymyr Savchenko from the INTEGRAL Science Data Centre, who led the analysis of the INTEGRAL data.

With facilities spread across the globe and in space, scientists now have the capability to detect a plethora of ‘cosmic messengers’ travelling vast distances at extremely high speeds, in the form of light, neutrinos, cosmic rays, and even gravitational waves.

“The ability to globally marshal telescopes to make a discovery using a variety of wavelengths in cooperation with a neutrino detector like IceCube marks a milestone in what scientists call multi-messenger astronomy,” says Francis Halzen from the University of Wisconsin–Madison, USA, lead scientist for the IceCube Neutrino Observatory.

By combining the information gathered by each of these sophisticated instruments to investigate a wide range of cosmic processes, the era of multi-messenger astronomy has truly entered the phase of scientific exploitation.

ESA’s high-energy space telescopes are fully integrated into this network of large multi-messenger collaborations, as demonstrated during the recent detection of gravitational waves with a corresponding gamma-ray burst – the latter detected by INTEGRAL – released by the collision of two neutron stars, and in the subsequent follow-up campaign, with contributions by INTEGRAL as well as the XMM-Newton X-ray observatory.

Pooling resources from these and other observatories is key for the future of astrophysics, fostering our ability to decode the messages that reach us from across the Universe.

“INTEGRAL is the only observatory available in the hard X-ray and soft gamma-ray domain that has the ability to perform dedicated imaging and spectroscopy, as well as having an instantaneous all-sky view at any time,” notes Erik Kuulkers, INTEGRAL project scientist at ESA.

“After more than 15 years of operations, INTEGRAL is still at the forefront of high-energy astrophysics.”


[1] Described by Frederick Reines, one of the scientists who made the first neutrino detection, as “… the most tiny quantity of reality ever imagined by a human being,” one neutrino is estimated to contain one millionth of the mass of an electron.

[2] The IceCube Collaboration is funded primarily by the National Science Foundation and is operated by a team headquartered at the University of Wisconsin–Madison, USA. The research efforts, including critical contributions to the detector operation, are supported by funding agencies in Australia, Belgium, Canada, Denmark, Germany, Japan, New Zealand, Republic of Korea, Sweden, Switzerland, the United Kingdom, and the USA.

[3] These results are detailed in the paper “Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A” by The IceCube, Fermi-LAT, MAGIC, AGILE, ASAS-SN, HAWC, H.E.S.S, INTEGRAL, Kanata, Kiso, Kapteyn, Liverpool telescope, Subaru, Swift/NuSTAR, VERITAS, and VLA/17B-403 teams, published in Science: http://science.sciencemag.org/cgi/doi/10.1126/science.aat1378

Related article:

NASA’s Fermi Traces Source of Cosmic Neutrino to Monster Black Hole

ESA’s INTEGRAL gamma-ray observatory: http://sci.esa.int/integral

ESA’s XMM-Newton X-ray observatory: http://sci.esa.int/xmm-newton/60376-cosmic-blast-takes-rest-at-last/

Images (mentioned), Text, Credits: ESA/Markus Bauer/Erik Kuulkers/INTEGRAL Science Data Centre/University of Geneva/Volodymyr Savchenko/Carlo Ferrigno/IceCube/University of Wisconsin–Madison/Francis Halzen/Sílvia Bravo Gallart.

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Mapping of ancient citadel shines new light on Bolivia’s Tiwanaku civilization

The creation of a topographical map of the ancient citadel of Tiwanaku, some 71 kilometers (44 miles) west of Bolivia’s capital of La Paz, has been made possible by a UNESCO-sponsored project helmed by Spanish archaeologist Jose Ignacio Gallegos.

Mapping of ancient citadel shines new light on Bolivia's Tiwanaku civilization
The ruins of the Kalasasaya courtyard in Tiwanako, Bolivia [Credit: Martin Alipaz/EPA-EFE]

“Discovering this site map is one of those things that don’t usually happen to scientists,” Gallegos told EFE, adding that he had been studying the Tiwuanaku civilization for years when he was offered the job.

The mapping – which was done with the help of high-tech drones and satellites – uncovered an assortment of buried public buildings and housing complexes spread throughout a 748-hectare (1,848-acre) surface.

Mapping of ancient citadel shines new light on Bolivia's Tiwanaku civilization
The ruins of the Kalasasaya courtyard in Tiwanako, Bolivia [Credit: Martin Alipaz/EPA-EFE]

“Tiwanaku is one of the most interesting civilizations because we don’t know a lot about it,” he said. “We have been researching it for almost 150 years and a myriad details still escape us.”

Tiwanaku – which was the capital of the eponymous pre-Columbian empire – is home to the remains of the Kalasasaya courtyard, the Gate of the Sun and the Semi-Subterranean Temple.

Mapping of ancient citadel shines new light on Bolivia's Tiwanaku civilization
The ruins of the Kalasasaya courtyard in Tiwanako, Bolivia [Credit: Martin Alipaz/EPA-EFE]

According to some Bolivian researchers, the Tiwanaku civilization started out as a village around 1580 BC, becoming an imperial state by 724 AD and finally falling around 1187.

The site was added to the UNESCO World Heritage List in 2000 and still holds great spiritual significance to the Andean world.

Mapping of ancient citadel shines new light on Bolivia's Tiwanaku civilization
Topographical map of Tiwanako, Bolivia [Credit: Jose Ignacio Gallegos]

For that reason, the citadel is the scene of the Aymara New Year celebration every June 21 and has been chosen as the site for President Evo Morales’s investiture as leader of all indigenous peoples following his electoral victories of 2006, 2010 and 2015.

Author: Elena Rodriguez | Source: EFE-EPA [July 09, 2018]




Mummies, embalming equipment discovered south of Pyramid of Unas in Egypt’s Saqqara

The Ministry of Antiquities is set to announce the discovery of a number of mummies and embalming equipment at the Saqqara necropolis on Saturday.

Mummies, embalming equipment discovered south of Pyramid of Unas in Egypt's Saqqara
The Pyramid of Unas, Saqqara [Credit: Tiziana Giuliani]

The ministry told Ahram Online that the discovery includes a collection of inscribed mummification vessel measuring cups.

A communal burial shaft was also discovered where a large number of mummies were buried.

The mummies were buried in both wooden coffins and large sarcophagi, and amulets, gemstones and precious metal objects were found.

A golden mask that was discovered will be displayed along with other objects during a press conference held by the ministry on Saturday.

The discovery was made in collaboration with a German archaeological mission, close to the Pyramid of Unas.

Author: Nevine El-Aref | Source: Ahram Online [July 09, 2018]




Evolution does repeat itself after all

For every two species of mammal there is one species of cichlid fish, which goes to show that biodiversity is distributed rather unevenly among animals. But why? And to what extent can evolution be predicted? A variety of “internal” as well as ecological factors play a role. One decisive factor could be ecological conditions, i.e. the number of different habitats and the similarity of ecological niches available. That is one reason for why there are so many species in the tropics. The demographic history of a population can also influence biological diversity: Is the level of genetic variation in a population sufficient to allow it to adapt to ecological niches? Did the population have enough time to do so? Quantifying all potential factors that contribute to biological diversity, even for only one group of animals, is not easy, not to mention that comparing mammals with a group of fish would be like comparing apples and oranges.

Evolution does repeat itself after all
The map shows the geographic distribution and morphological diversity of the various species and ecotypes
of Midas cichlids that occur in Lakes Nicaragua and Managua as well as in various crater lakes
[Credit: Andreas Kautt]

The fallacy of comparing apples and oranges is something that Dr Andreas Kautt, who is now a post-doctoral researcher at Harvard University, is acutely aware of. It does not apply to his research, however, since during his doctoral studies at the University of Konstanz he focused entirely on cichlids. His studies demonstrate just how “deterministic” evolution can be – even among as diverse a family as cichlids, a paramount example of evolutionary diversity and “creativity”.

“Imagine 500 to 1,000 species of cichlids living in one of the African Great Lakes, one of the largest freshwater habitats in the world. The degree of complexity is unimaginable. Even the genealogical relationships between the cichlid species living in these lakes have only partially been resolved”, says Professor Axel Meyer’s former doctoral student. Meyer’s evolutionary biology team, which is based at the University of Konstanz and is funded by an ERC Advanced Grant in the amount of € 2.5m, currently pursues a project that seeks to answer the following questions: Why does nature produce this unimaginable amount of different species? What are the origins of biodiversity? How predictable is evolution? Why does evolution repeat itself?

In a new publication in the journal Evolution Letters, Axel Meyer, Andreas Kautt and Dr Gonzalo Machado-Schiaffino, a former staff member in Meyer’s research team who is now an assistant professor at the University of Oviedo in Spain, are able to identify some of the factors that contribute to recurrent patterns of diversity and similarity in cichlids. Andreas Kautt puts the question prompted by their findings like this: “Which factors lead to similar outcomes and thereby help us predict evolution?”

Since the African Great Lakes are incredibly diverse, Axel Meyer’s research team focuses not only on them, but also studies a more recent and simple “natural evolutionary experiment” involving parallel species of Nicaraguan Midas cichlids, which occur in the two great lakes as well as in a chain of crater lakes in Nicaragua. They investigate the morphology, population genetics and habitats of the crater lake populations, comparing the results with those results obtained for members of the source population living in the great lakes of Nicaragua. Due to their smaller size, the crater lakes are not only less complex. An added advantage is that their maximum age has been determined. From an evolutionary perspective, with an age of between 1,000 and 24,000 years, they are very young, which makes them easier to study.

Also, the crater lakes are isolated and their faunas all stem from the same older and larger source lakes. “The crater lake populations effectively represent natural evolutionary experiments”, explains Andreas Kautt.

Based on statistical analyses of ecological data and a large amount of genetic information, Kautt et al. arrive at the following conclusion: “The more similar the habitat of the crater lake is to that of the large source lake, the more similar the fish are to each other”. This suggests that it is the habitats – and not demographic criteria – that are decisive for the predictability of diversity. The data collected by the University of Konstanz biologists shows that, compared to the source population, the morphology of all crater lake populations has diversified mostly in the same direction: The crater lake fish all very quickly evolved body shapes that are longer and more slender than those of their cousins from the great lakes.

The importance of these ecological factors can further be demonstrated by the fact that the diverse body shapes of the crater lake populations are closely related to the average depth of the lakes. Andreas Kautt comments: “It makes sense. The deeper a lake is, the more likely it is to provide various ecological niches, including in the deep open water”. All of this leads the researchers to conclude that, under certain conditions, evolutionary outcomes can be predicted.

Source: University of Konstanz [July 10, 2018]




Uncovering the lost world of New Zealand from fossil bone DNA

Curtin University researchers have used DNA from fossil bones to reconstruct the past biodiversity of New Zealand, revealing a history of extinctions and biodiversity decline since human arrival there about 750 years ago.

Uncovering the lost world of New Zealand from fossil bone DNA
Overall biodiversity of excavated bulk bone. Species composition was analyzed using four metabarcoding assays targeting
vertebrate taxa. (A) Dendrogram highlighting the diversity of orders identified in all samples, with examples of taxa
identified in silhouettes. Bar sizes represent the number of taxa identified in each order. (B) Sample localities of
archaeological midden sites (red triangles) and paleontological deposits (gray triangles). (C) Correspondence analysis
based on presence/absence of all taxa identified from archaeological or paleontological sites. The distribution of
herpetofauna (Class: Amphibia and Reptilia), fish species (Class: Actinopterygii and Chondrichthyes), and marine
mammals (Family: Phocidae and Otariidae and Order: Cetacea) is highlighted by ellipses of incremental
confidence intervals of 0.4, 0.6, and 0.8 [Credit: Frederik V. Seersholm et al. PNAS 2018]

The research, which was published in Proceedings of the National Academy of Sciences, characterised DNA preserved in fragmented and unidentifiable bones from across New Zealand.

By comparing bones excavated from caves that predate human arrival with bones from ancient human kitchen waste (or middens), the researchers were able to characterise the biodiversity that had been lost in New Zealand.

Lead author Curtin PhD candidate Mr Frederik Seersholm, from Curtin’s School of Molecular and Life Sciences, said causes of extinctions were usually hard to identify due to the time that had passed since it happened.

“However, through this study, we were able to examine in more detail the first contact between people and fauna in New Zealand because it only happened 750 years ago,” Mr Seersholm said.

“The research also identified a large faunal diversity with DNA from more than 100 different species uncovered, including 14 species that are extinct today.

“Our results demonstrate that certain species tend to be missed by traditional research methods. For example, we identified species of eel and whale in Maori middens previously unknown in the prehistoric Maori diet.”

The research was undertaken by an international study team led by Distinguished Research Fellow Professor Michael Bunce, also from Curtin’s School of Molecular and Life Sciences, including academics from University of Otago, Canterbury Museum and Museum of New Zealand Te Papa Tongarewa.

The research team analysed DNA from more than 5000 bone fragments collected from 21 archaeological middens and 15 paleontological caves in New Zealand.

Professor Bunce said the researchers sequenced genetic signatures to identify different species and characterise different genetic lineages within one species.

“For the ground dwelling parrot, the kakapo, surprisingly high amounts of genetic diversity was detected in the bone fragments, which demonstrates that the kakapo population has been declining since human arrival in New Zealand 750 years ago,” Professor Bunce said.

“Of the ten kakapo lineages we identified, only one is still around today and this is an indication of the amount of biodiversity lost from one of New Zealand’s iconic flightless birds.”

Mr Seersholm said the findings demonstrate how much information is stored in seemingly insignificant bone fragments.

“There is without doubt a great deal of information to be retrieved from fragmented bones, and it is likely that important future discoveries on extinct species and past biodiversity are hidden in neglected excavation bags in the basements of museums and universities around the globe,” Mr Seersholm said.

Source: Curtin University [July 10, 2018]




The study of neanderthals’ tartar reveals the widespread consumption of plants as a...

Domingo C. Salazar, an Ikerbasque researcher at the UPV/EHU, and Robert C. Power of the Max-Plank Institute for Evolutionary Anthropology have studied pieces of dental calculus or tartar of the Neanderthals to find out about their diet.

The study of neanderthals’ tartar reveals the widespread consumption of plants as a subsistence strategy
A closeup of the Neanderthal teeth shows dental calculus deposits as a rind on the tooth enamel
[Credit: Royal Belgian Institute of Nature Science]

The Neanderthals (Homo neanderthalensis) inhabited Europe and parts of Western Asia between 230,000 and 28,000 years ago, coinciding during the final millennia with Homo Sapiens, and died out for reasons that are still being disputed; what actually became of the Neanderthals has fascinated and continues to fascinate researchers across the world.

The most popular idea is that the disappearance of the Neanderthals was caused by the greater competition of the ancestors of modern humans, Homo Sapiens, who appeared more or less at the same time as the Neanderthals disappeared from Europe, and one of the explanations as to how that happened could be their diet. The Neanderthals are thought to have had more limited diets, while our ancestors had more flexible, adaptive diets that included seafood and a variety of plants.

Yet even though archaeological science has advanced considerably over the last few decades and has come up with new theories about the diets of the Neanderthals, today we still only have a patchy image of their dietary ecology given that we lack full, environmentally representative information about how they used plants and other foods.

The study of neanderthals’ tartar reveals the widespread consumption of plants as a subsistence strategy
Microremains of a variety of plants, some of which represent the dietary foods
of the Neanderthals [Credit: UPV/EHU]

This new piece of research into the fragments of dental calculus or tartar shows that the use of plants was a widespread, deeply-rooted subsistence strategy of the Neanderthals.

Yet when modelling the various diets of more current gatherers from the Tropics right up to the Arctic, it has not been possible to find traces of dietary variation in terms of time and space in the consumption of plant food. This could mean that the consumption of plants by the Neanderthals was widespread, but limited to a specific type of plant or vegetable, unlike the way in which modern humans ate.

According to Domingo C. Salazar, “rather than being a sign of primitiveness, this way of eating reflects a strategy that was simply followed over thousands of years because of its effectiveness”.

The findings are published in the Journal of Human Evolution.

Source: The University of Basque Country [July 10, 2018]




Julius Caesar may have been less heroic than previously imagined

The world-renowned general Julius Caesar may have been rather less heroic than we imagine, in terms of victories as well as physique. Caesar was largely bald and had a deformed skull, resulting from difficulties during his birth. As for military campaigns, he suffered his greatest defeat in the Low Countries, possibly near the Dutch city of Maastricht, according to new research suggesting that he fought a substantial proportion of the Gallic Wars in the northern part of Gaul.

Julius Caesar may have been less heroic than previously imagined
An assistant holds a 3D reconstruction of Roman emperor and military general Julius Caesar at The National
Museum of Antiquities in Leiden, The Netherlands. The reconstruction was made on the basis of a 3D scan
of a marble portrait in the museum’s collection [Credit: Remko de Waal/ANP/AFP]

These findings emerged from the research conducted by the archaeologist and author Tom Buijtendorp on Caesar’s activities in the Low Countries, in response to the mounting pile of clues for his presence here. Buijtendorp’s research was recently published in the book Caesar in de Lage Landen (Caesar in the Low Countries). His findings about Caesar’s countenance in combination with one of the oldest portraits of Caesar from the collection of the Dutch national museum of antiquities (the Rijksmuseum van Oudheden in Leiden), were the basis for an alternative ’new’ face. The reconstruction of this face is currently on show in the museum.

The face of Julius Caesar 

Recently, on 22 June 2018, a lifelike interpretation of the general’s ‘new’ face was presented at the Rijksmuseum van Oudheden, in which the asymmetric shape of the skull and the receding hairline differ significantly from the traditional images. According to Buijtendorp, Caesar’s head displays clear signs of a difficult birth – a new fact in Caesar’s biography. The specific skull abnormality enabled Buijtendorp to identify the so called Tusculum bust (Museo Archeologico, Turin) as the most authentic portrait of Caesar, which differs markedly from the marble posthumous busts that are most commonly displayed, and fits well with Caesars contemporary coin portrait.

Subsequently archaeologist and physical anthropologist Maja d’Hollosy was asked to make an alternative, more lifelike ‘Caesar of the Low Countries’, so to speak, based on one of the Caesar portraits from the collection in Leiden. Sources as the Tusculum bust and the coin portrait were used to add the missing features. Furthermore Buijtendorp’s research gave instructions about skin and eye colour, and hair. The result is a mix between the three sources, with the museum bust as base. Since a 100 percent reliable sources were lacking, a major aim was to make Caesar more alive, not creating the ultimate Ceasar bust.

Julius Caesar may have been less heroic than previously imagined
Reconstruction of Julius Caesar and a portrait bust of him from the collection of the Rijksmuseum van Oudheden
[Credit: Maja d’Hollosy/RMO]

According to Buijtendorp, this reconstruction of Caesar’s portrait reminds us that the traditional image of Caesar is unrealistic, but also shows the remaining uncertainties about details like the eyes: ‘Though the new version likewise does not represent an absolute truth, it does provide a more credible alternative to the existing picture, rejecting the symmetric head of hair image we got used to’.

The reconstruction was made possible by financial support from the Dutch province of South Holland.

A less heroic Caesar 

The reconstruction of Caesars looks, symbolizes we have to reconsider Caesar’s image in a wide sense. His own statistics on killed Roman soldiers, suggest that roughly half of these deaths took place in the north, in Gallia Belgica. In this harsh northern region Caesar encountered his largest defeat ever, and faced a second defeat at the same place the year after. The northern military effort was so burdensome that Caesar had to limit his British ambition. Caesar’s idea of the Rhine as natural border, would impact the strategy of the Roman Empire for a long time.

Buijtendorp’s research for his book Caesar in de Lage Landen (Caesar in the Low Countries) was based in part on recently-excavated Caesarian camps, an analysis of indigenous gold coins, geographical analyses, and a renewed assessment of Caesar’s own statistics. The findings for example suggests that a hilltop stronghold near Maastricht may have served in 54 and 53 BC as the camp and logistics centre of Caesar’s army, site of his largest loss.

This is indicated, for instance, by a detailed analysis of gold coins and the camp’s size, which was recently established. Caesars description of the battle site fits quite well with the environment. In addition, the site becomes a logical choice when looking at the reconstruction of Caesars northern campaign. And new insights in the possible location of other camps, also provide a possible match. Like in more cases, this new perspective generates a working hypothesis that may help to actually discovery archaeological remains and protect sites.

The recently recognized unique shape of the hobnails in the boots of Caesar’s soldiers, since 2010 enabled researchers to link three northern camps to Caesar. New discoveries may follow, for which the book – which is written in the manner of a travel guide – identifies several possible sites. This remains challenging for marching camps. A large excavation at Limburg-Eschhofen only revealed three hobnails, while at Hermeskeil a gate probably used for several months was a special hobnail find spot. Mauchamp with clear old traces of Caesars’ large camp, did not provide related finds lacking sizeable modern excavations.

Much work lies ahead 

Buijtendorp emphasises that his research is only the beginning. ‘Given the growing fund of clues for Caesar’s presence in the Low Countries, new work lies ahead. The research presented here will hopefully serve as a basis for further studies to test various hypotheses, as much remains uncertain.’

Source: Rijksmuseum van Oudheden [July 12, 2018]





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