суббота, 9 февраля 2019 г.

360 Video: Curiosity Rover Departs Vera Rubin Ridge


NASA – Mars Science Laboratory (MSL) logo.


February 9, 2019



Image above: This panorama from the Mast Camera (Mastcam) on NASA’s Curiosity Mars rover was taken on Dec. 19 (Sol 2265). The rover’s last drill location on Vera Rubin Ridge is visible, as well as the clay region it will spend the next year exploring. Image Credits: NASA/JPL-Caltech/MSSS.


After exploring Mars’ Vera Rubin Ridge for more than a year, NASA’s Curiosity rover recently moved on. But a new 360-video lets the public visit Curiosity’s final drill site on the ridge, an area nicknamed “Rock Hall.” The video was created from a panorama taken by the rover on Dec. 19. It includes images of its next destination – an area the team has been calling the “clay-bearing unit” and recently named “Glen Torridon” – and the floor of Gale Crater, home to Mount Sharp, the geological feature the rover has been climbing since 2014.



NASA’s Curiosity Mars Rover Departs Vera Rubin Ridge (360 View)

Even though the rover has left the ridge, Curiosity’s team is still piecing together the story of its formation. While there have been a number of clues so far, none fully explains why the ridge has resisted erosion compared with the bedrock around it. But the rover’s investigation did find that the rocks of the ridge formed as sediment settled in an ancient lake, similar to rock layers below the ridge.


“We’ve had our fair share of surprises,” said Curiosity science team member Abigail Fraeman of NASA’s Jet Propulsion Laboratory in Pasadena, California. “We’re leaving with a different perspective of the ridge than what we had before.”


A NASA orbiter studying the ridge had previously identified a strong signal from hematite, an iron-rich mineral that often forms in water. Curiosity confirmed the presence of hematite, along with other signs of ancient water, like crystals. These signs appeared in patches, leading the team to suspect that over time groundwater affected certain parts of the ridge differently than others. Another discovery was that the hematite signatures Curiosity mapped didn’t always match the view from space.


“The whole traverse is helping us understand all the factors that influence how our orbiters see Mars,” Fraeman said. “Looking up close with a rover allowed us to find a lot more of these hematite signatures. It shows how orbiter and rover science complement one another.”


The ridge has also served as the backdrop to a roller-coaster year: Curiosity’s drill returned to action, only to be stymied by surprisingly hard rocks. Nevertheless, the team managed to get samples from the three major rock types of the ridge. To get around a memory issue, engineers also swapped the rover’s computers (the spacecraft was designed with two so that it can continue operations if one experiences a glitch). While the issue is still being diagnosed, operations have continued with little impact on the mission.



Image above: A selfie taken by NASA’s Curiosity Mars rover on Sol 2291 (January 15) at the “Rock Hall” drill site, located on Vera Rubin Ridge. Image Credits: NASA/JPL-Caltech/MSSS.


The rover’s new home, Glen Torridon, is in a trough between Vera Rubin Ridge and the rest of the mountain. This region had been called the clay-bearing unit because orbiter data show that the rocks there contain phyllosilicates – clay minerals that form in water and that could tell scientists more about the ancient lakes that were present in Gale Crater off and on throughout its early history.


“In addition to indicating a previously wet environment, clay minerals are known to trap and preserve organic molecules,” said Curiosity Project Scientist Ashwin Vasavada of JPL. “That makes this area especially promising, and the team is already surveying the area for its next drill site.”


Curiosity has found both clay minerals and organic molecules in many of the rocks it has drilled since landing in 2012. Organic molecules are the chemical building blocks of life. If both water and organic molecules were present when the rocks formed, the clay-bearing unit may be another example of a habitable environment on ancient Mars – a place capable of supporting life, if it ever existed.


For more about NASA’s Curiosity Mars rover mission, visit: https://mars.jpl.nasa.gov/msl


Image (mentioned), Video, Text, Credits: NASA/JPL/Andrew Good.


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Paging Doctor Bat From Bram Stoker’s Dracula to modern-day…


Paging Doctor Bat


From Bram Stoker’s Dracula to modern-day horror movies, vampire bats like this one get a bad rap. In fact, vampire bats only rarely feed on human blood, usually only resorting to snacking on unsuspecting sleeping humans when their regular sources of food like farm animals are thin on the ground. These bats could even provide benefits for human health: scientists have discovered that the chemicals they produce in their venom in order to relax blood vessels and keep the red stuff flowing from their prey could be used to treat a range of conditions from high blood pressure and heart failure to kidney disease and burns. Right now the work is on hold, though, as violent drug trafficking gangs have taken over the area in Mexico where the bats live, making it unsafe for researchers to visit. Sadly, real people are much more dangerous than these vampires could ever be.


Written by Kat Arney



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Монограмма двух пространств 2.02.2019

Круги на полях Англии зимой  на Круглом холме, Девизес, Уилтшир. 2 февраля 2019


Суббота Круги на снегу




Фотограф-беспилотник  у Крис Барроу, 59 лет





https://metro.co.uk/2019/02/04/massive-owl-face-appears-snow-aliens-move-crop-circles-8435104/


http://www.fgk.org/?cat=375


Swinside or Sunkenkirk Prehistoric Stone Circle, Lake District, 9.2.19.One of my...


Swinside or Sunkenkirk Prehistoric Stone Circle, Lake District, 9.2.19.


One of my favourites…


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2019 February 9 Comet Iwamoto and the Sombrero Galaxy Image…


2019 February 9


Comet Iwamoto and the Sombrero Galaxy
Image Credit & Copyright: Ian Griffin (Otago Museum)


Explanation: Comet Iwamoto (C/2018 Y1), shows off a pretty, greenish coma at the upper left in this telescopic field of view. Taken on February 4 from the Mount John Observatory, University of Canterbury, the 30 minute long total exposure time shows the comet sweeping quickly across a background of stars and distant galaxies in the constellation Virgo. The long exposure and Iwamoto’s rapid motion relative to the stars and galaxies results in the noticeable blurred streak tracing the the comet’s bright inner coma. In fact, the streaked coma gives the comet a remarkably similar appearance to Messier 104 at lower right, popularly known as the Sombrero Galaxy. The comet, a visitor to the inner Solar System, is a mere 4 light-minutes away though, while majestic Messier 104, a spiral galaxy posing edge-on, is 30 million light-years distant. The first binocular comet of 2019, Iwamoto will pass closest to Earth on February 12. This comet’s highly elliptical orbit around the Sun stretches beyond the Kuiper belt with an estimated 1,371 year orbital period. That should bring it back to the inner Solar System in 3390 AD.


∞ Source: apod.nasa.gov/apod/ap190209.html


SlingShot Tests Small Satellite Deployment and Payload Hosting Capabilities


ISS – International Space Station logo.


Feb. 8, 2019



SlingShot on Cygnus Spacecraft. Image Credit: NASA

Launching satellites is a growing business. A new platform that could bolster satellite deployment opportunities in space seeks to service this burgeoning economy. SlingShot, by the company SEOPS, is designed to deploy CubeSats at altitudes above the station using the infrastructure offered by the International Space Station in partnership with the U.S. National Laboratory and Northrop Grumman.


SlingShot arrived at the orbiting laboratory aboard the SpaceX CRS-16 mission in early December. During this flight, the company is testing every aspect of the technology’s potential uses while also deploying satellites for SEOPS’ clients.



Animation above: The Cygnus Spacecraft leaves the ISS with SlingShot payloads in preparation for deployment activities. Animation Credit: NASA.


SlingShot was designed to launch on any cargo vehicle. For this mission it was transferred from the SpaceX vehicle to the Cygnus vehicle attached to the station and then loaded with satellites for deployment when Cygnus departs from the station.


After Cygnus leaves the station, the cargo craft will navigate to approximately 310 miles (500 kilometers) above the Earth, approximately 62 miles higher than the space station’s orbit. There, Slingshot deploys two satellites, expected to stay in orbit at least two years. In addition, a mounted payload will test SlingShot’s capability to host fixed payloads for an extended period, where the payload uses Cygnus’ power, attitude control and communication capabilities.


SlingShot’s approach to satellite deployment builds on previous efforts made by other companies and international partners. Most previous deployments from the space station were at lower altitude orbits that degrade within months, limiting the useful life of the satellites.



Animation above: ISS Crew members David Saint-Jacques and Anne Mcclain installed two Slingshot deployables, SEOPS-Quantum Radar -1 and -2s, onto the outer hatch of the Cygnus Spacecraft. Also installed in a deployable slot is the UbiquityLink-1 orbit to ground communications hardware. The two passive optical reflector satellites will be released after Cygnus moves away from the ISS. Animation Credit: NASA.


“That is a great orbit for test demos,” said Chad Brinkley, principal investigator for the facility, “but if you look at the market for where rockets are trying to go, 500 km is ideal for closing a business case for companies that are considering flying CubeSats to give them revenue from a satellite for two plus years.”


The satellites SlingShot accommodates are modular small satellites called CubeSats that come in different configurations. Brinkley noted, “Our system is so flexible, we can accommodate the different CubeSat formats – all of them!”


One surprise to the development team has been the level of interest in the payload hosting capability. Fixed mounted payloads do not require adding avionics and a bus, so the development cost is significantly lower than developing a satellite. Additionally, the payload “can use Cygnus’ power and data as well as point the payload,” said Brinkley.



Animation above: NASA Astronaut Anne Mcclain installs a data cable and controller to prepare SlingShot for operations. Modular in design, SlingShot can hold up to nine deployers that can launch CubeSats of multiple sizes or can host fixed payloads that remain rigidly attached to Cygnus to gather and transmit data while the vehicle is in orbit. Animation Credit: NASA.


SEOPS worked closely with NASA to develop and get approval for SlingShot in less than a year. The company contracted directly with Northrop Grumman for the non-recurring engineering to integrate SlingShot with Cygnus and worked with the U.S. National Laboratory to receive their allocation, securing space for transportation as well as crew time for installation of the hardware. “For a commercial company, this is to me a great model for how you can do business with NASA and other commercial companies,” said Brinkley.


“We’re excited about having an opportunity to do this,” Brinkley said, “I feel like we’re executing the vision for commercialization of space.”


Related links:


SlingShot: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7847


U.S. National Laboratory: https://www.issnationallab.org/


Northrop Grumman: http://www.northropgrumman.com/Pages/default.aspx


SpaceX CRS-16: https://www.nasa.gov/mission_pages/station/research/news/spx16-research


CubeSats: https://www.nasa.gov/mission_pages/station/research/news/cubesats_possibilities


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


Image (mentioned), Animations (mentioned), Text, Credits: NASA/Michael Johnson/JSC/International Space Station Program Science Office/Carrie Gilder.


Best regards, Orbiter.chArchive link


Around the World in Seven Ground Stations

Happy Birthday, Jules Verne!


image


Considered by many to be the father of science fiction,

French novelist Jules Verne takes his readers on a “From the Earth to the Moon,” “Twenty Thousand Leagues Under the Sea” and “Around the World in

Eighty Days.” In his honor, let’s take our own journey around the world,

exploring seven far-flung ground stations and the communications networks they

support. These ground stations downlink data from science and exploration

missions, maintaining the critical link from space to ground.


image

Our Deep Space Network supports

far-out missions like Voyager 1, a spacecraft that’s

now over 13 billion miles from Earth. To communicate that far, the Network uses

antennas as large as 230 feet in diameter. The network has ground stations in

Pasadena, California; Madrid, Spain; and this one in Canberra, Australia. The

ground stations are strategically placed for maximum coverage of the night sky,

ensuring that deep space missions can communicate their data back to Earth.

Check out that lizard!


image

Our Space Network uses relay satellites in conjunction with ground stations to

provide continuous communications coverage for satellites in low-Earth orbit

like the International

Space Station
, enabling 24/7 connection with astronauts onboard.

Spacecraft using the Space Network beam their data to the constellation of Tracking and Data

Relay Satellites
, which forward that data to the ground. This is a

photo of a Space Network ground station in Guam, a U.S. territory. The

spherical structures around the antennas are called “radomes” and protect the

antennas from the tropical storms!


image

Optical

communications
uses lasers to provide missions with higher data

rates than radio communications. Optical terminals also offer missions reduced

size, weight and power requirements over comparable radio antennas. A smaller

system leaves more room for science instruments, a weight reduction can mean a

less expensive launch and reduced power allows batteries to last longer. This

ground station in Haleakalā, Hawaii, will relay data to California through a

groundbreaking optical communications satellite, the Laser Communications Relay Demonstration.

The demonstration will show the power and promise of optical communications to

support the next generation of science missions.


image

Antarctica may seem like an odd place for radio antennas,

but McMurdo Ground Station is vitally important to our networks. In 2017, we

used the McMurdo ground station to demonstrate a new technology

called Disruption

Tolerant Networking
(DTN), sending a selfie from McMurdo to the

space station through numerous DTN nodes. DTN protocols allow data to be stored

at points along its route that do not have an open connection to the next

intermediary, preventing data loss and improving data returns.


image

This Near Earth Network ground station in Santiago, Chile,

might not be our only South American ground station for long. The Near Earth

Network is considering Punta Arenas, Chile, as a possible location for Ka-band

antennas, which would provide missions with higher data rates. The Near Earth

Network is also experimenting with Ka-band arraying, which uses multiple

smaller antennas to provide the same capabilities of a larger, Ka-band antenna.

Ka-band services will greatly increase the amount of science data we can

gather!


image

If the space station ever has communications trouble, we

could communicate with our astronauts through emergency very high frequency

(VHF) communications ground stations like this one in Wallops Island, Virginia.

VHF offers voice-only, contingency communications for the station and the Soyuz

spacecraft, which ferries astronauts to and from the station. We maintain two

VHF stations strategically placed to maximize contact with the space station as

it orbits above North America. International partners operate VHF stations that

provide contacts as the station orbits above Asia and Europe. NASA’s segment of

the VHF network recently underwent critical upgrades that improve

the reliability and durability of the system.


image

This beautiful photo captures Near Earth Network antennas in

Svalbard, Norway, beneath the glow of the Northern lights, a phenomenon that

occurs when charged particles from the Sun interact with various gasses in

Earth’s atmosphere. If one were to visit Iceland, one could see these same

lights above Snæfellsjökull volcano, featured in Jules Verne’s “A Journey to

the Center of the Earth” as the imaginary entrance to a subterranean world.


A lot has changed in the nearly two centuries since Jules

Verne was born. Verne’s 1865 novel “From the Earth to the Moon” and its 1870

sequel “Around the Moon” imagine a giant cannon capable of launching three men

into lunar orbit. These imaginary astronauts used opera glasses to survey the

lunar surface before returning safely to Earth.


Such a story may seem ridiculous in an age where humanity

has occupied space for decades and satellites explore distant worlds with

increasing regularity, but Verne’s dreams of spaceflight were novel ­– if not

revolutionary – at the time. This change in worldview reflects humanity’s

inexorable technological progress and our mission at NASA to turn science

fiction into science fact.


As the next generation of exploration commences, our

ever-evolving communications capabilities rise to meet the demands of missions

that dreamers like Verne could hardly imagine.


The seven ground

stations featured here were just a taste of our communications infrastructure.

To learn more about space communications, visit: https://www.nasa.gov/SCaN


Astronauts Release U.S. Spacecraft from Station



ISS – Expedition 58 Mission patch / Northrop Grumman – Cygnus NG-10 Mission patch.


February 8, 2019


Northrop Grumman’s Cygnus spacecraft was released from the Canadarm2 at 11:16 a.m. EST and has departed the International Space Station. After an extended mission to deploy several CubeSats in multiple orbits, Cygnus is scheduled to be deorbited on Feb. 25 to enter the Earth’s atmosphere and burn up harmlessly over the Pacific Ocean.


Expedition 58 Flight Engineers Anne McClain of NASA and David Saint-Jacques of the Canadian Space Agency used the station’s robotic arm to release the craft, dubbed the “SS John Young”, after ground controllers unbolted the cargo vehicle from the Earth-facing port of the Unity module earlier this morning.



Image above: The Cygnus is pictured moments after its release from the Canadarm2 robotic arm. Image Credit: NASA TV.


This Commercial Resupply Services contract mission delivered dozens of new and existing investigations as Expedition 58 contributes to some hundreds of science and research studies. Highlights from the new experiments include a demonstration of 3D printing and recycling technology and simulating the creation of celestial bodies from stardust.


The Refabricator is the first-ever 3D printer and recycler integrated into one user-friendly machine. Once it’s installed in the space station, it will demonstrate recycling of waste plastic and previously 3D printed parts already on-board into high-quality filament, or 3D printer “ink.” This recycled filament will be fed into the printer as stock to make new tools and parts on-demand in space. This technology could enable closed-loop, sustainable fabrication, repair and recycling on long-duration space missions, and greatly reduce the need to continually launch large supplies of new material and parts for repairs and maintenance. The demonstration, which NASA’s Space Technology Mission and Human Exploration and Operations Directorates co-sponsored, is considered a key enabling technology for in-space manufacturing. NASA awarded a Small Business Innovation Research contract valued to Tethers Unlimited Inc. to build the recycling system.



NG CRS-10: SS John Young Cygnus departure

The Experimental Chondrule Formation at the International Space Station (EXCISS) investigation will explore how planets, moons and other objects in space formed by simulating the high-energy, low-gravity conditions that were present during formation of the early solar system. Scientists plan to zap a specially formulated dust with an electrical current, and then study the shape and texture of the resulting pellets.


The Crystallization of LRRK2 Under Microgravity Conditions-2 (PCG-16) investigation grows large crystals of an important protein, leucine-rich repeat kinase 2 (LRRK2), in microgravity for analysis back on Earth. This protein is implicated in development of Parkinson’s disease, and improving our knowledge of its structure may help scientists better understand the pathology of the disease and develop therapies to treat it. LRRK2 crystals grown in gravity are too small and too compact to study, making microgravity an essential part of this research.  This investigation is sponsored by the International Space Station U.S. National Laboratory, which Congress designated in 2005 to maximize its use for improving quality of life on Earth.


Cygnus launched Nov. 17, 2018, on an Antares 230 rocket from Virginia Mid-Atlantic Regional Spaceport’s Pad 0A at Wallops, and arrived at the station Nov. 19 for the company’s 10th NASA-contracted commercial resupply mission to the station.


This was the seventh flight of an enhanced Cygnus spacecraft, and the fourth using Northrop Grumman’s upgraded Antares 230 launch vehicle featuring new RD-181 engines that provide increased performance and flexibility.


Related links:


Expedition 58: https://www.nasa.gov/mission_pages/station/expeditions/expedition58/index.html


Canadarm2: https://www.nasa.gov/mission_pages/station/structure/elements/mobile-servicing-system.html


Unity module: https://www.nasa.gov/mission_pages/station/structure/elements/unity


Refabricator: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7321


Small Business Innovation Research: http://sbir.nasa.gov/#_blank


Tethers Unlimited Inc.: http://www.tethers.com/#_blank


Experimental Chondrule Formation at the International Space Station (EXCISS): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7785


Crystallization of LRRK2 Under Microgravity Conditions-2 (PCG-16): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7855


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


Image (mentioned), Video, Text, Credits: NASA/Mark Garcia/NASA TV/SciNews.


Best regards, Orbiter.chArchive link


Hubble Reveals Dynamic Atmospheres of Uranus and Neptune



Uranus  and Neptune

Credits: NASA, ESA, A. Simon (NASA Goddard Space Flight Center), 

and M.H. Wong and A. Hsu (University of California, Berkeley)


During its routine yearly monitoring of the weather on our solar system’s outer planets, NASA’s Hubble Space Telescope has uncovered a new mysterious dark storm on Neptune (right) and provided a fresh look at a long-lived storm circling around the north polar region on Uranus (left).



Like Earth, Uranus and Neptune have seasons, which likely drive some of the features in their atmospheres. But their seasons are much longer than on Earth, spanning decades rather than months.


The new Hubble view of Neptune shows the dark storm, seen at top center. Appearing during the planet’s southern summer, the feature is the fourth and latest mysterious dark vortex captured by Hubble since 1993. Two other dark storms were discovered by the Voyager 2 spacecraft in 1989 as it flew by the remote planet. Since then, only Hubble has had the sensitivity in blue light to track these elusive features, which have appeared and faded quickly. A study led by University of California, Berkeley, undergraduate student Andrew Hsu estimated that the dark spots appear every four to six years at different latitudes and disappear after about two years.


Hubble uncovered the latest storm in September 2018 in Neptune’s northern hemisphere. The feature is roughly 6,800 miles across.


To the right of the dark feature are bright white “companion clouds.” Hubble has observed similar clouds accompanying previous vortices. The bright clouds form when the flow of ambient air is perturbed and diverted upward over the dark vortex, causing gases to freeze into methane ice crystals. These clouds are similar to clouds that appear as pancake-shaped features when air is pushed over mountains on Earth (though Neptune has no solid surface). The long, thin cloud to the left of the dark spot is a transient feature that is not part of the storm system.


It’s unclear how these storms form. But like Jupiter’s Great Red Spot, the dark vortices swirl in an anti-cyclonic direction and seem to dredge up material from deeper levels in the ice giant’s atmosphere.


The Hubble observations show that as early as 2016, increased cloud activity in the region preceded the vortex’s appearance. The images indicate that the vortices probably develop deeper in Neptune’s atmosphere, becoming visible only when the top of the storm reaches higher altitudes.


The snapshot of Uranus, like the image of Neptune, reveals a dominant feature: a vast bright cloud cap across the north pole.


Scientists believe this feature is a result of Uranus’ unique rotation. Unlike every other planet in the solar system, Uranus is tipped over almost onto its side. Because of this extreme tilt, during the planet’s summer the Sun shines almost directly onto the north pole and never sets. Uranus is now approaching the middle of its summer season, and the polar-cap region is becoming more prominent. This polar hood may have formed by seasonal changes in atmospheric flow.


Near the edge of the cloud cap is a large, compact methane-ice cloud, which is sometimes bright enough to be photographed by amateur astronomers. A narrow cloud band encircles the planet north of the equator. It is a mystery how bands like these are confined to such narrow widths, because Uranus and Neptune have very broad westward-blowing wind jets.


Both planets are classified as ice giant planets. They have no solid surface but rather mantles of hydrogen and helium surrounding a water-rich interior, itself perhaps wrapped around a rocky core. Atmospheric methane absorbs red light but allows blue-green light to be scattered back into space, giving each planet a cyan hue.


The new Neptune and Uranus images are from the Outer Planet Atmospheres Legacy (OPAL) program, a long-term Hubble project, led by Amy Simon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, that annually captures global maps of our solar system’s outer planets when they are closest to Earth in their orbits. OPAL’s key goals are to study long-term seasonal changes, as well as capture comparatively transitory events, such as the appearance of Neptune’s dark spot. These dark storms may be so fleeting that in the past some of them may have appeared and faded during multi-year gaps in Hubble’s observations of Neptune. The OPAL program ensures that astronomers won’t miss another one.


These images are part of a scrapbook of Hubble snapshots of Neptune and Uranus that track the weather patterns over time on these distant, cold planets. Just as meteorologists cannot predict the weather on Earth by studying a few snapshots, astronomers cannot track atmospheric trends on solar system planets without regularly-repeated observations. Astronomers hope that Hubble’s long-term monitoring of the outer planets will help them unravel the mysteries that still persist about these faraway worlds.


Analyzing the weather on these worlds also will help scientists better understand the diversity and similarities of the atmospheres of solar-system planets, including Earth.



Related Links


This site is not responsible for content found on external links





Contact

Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu


Amy Simon
NASA Goddard Space Flight Center, Greenbelt, Maryland
amy.simon@nasa.gov


Mike Wong
University of California, Berkeley, California
mikewong@astro.berkeley.edu





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Medieval inks for heritage conservation

The fact that historical archives, libraries, museums, writing workshops and even monasteries, currently conserve medieval manuscripts is not only a question of heroes or ordinary people who went through the trouble to save them, passing them down from one generation to the next, or who hid them so they would not be destroyed. The materials used to write and draw upon paper were crucial so that surviving written texts can be read, translated and interpreted nowadays.











Medieval inks for heritage conservation
Researchers have replicated five medieval inks using 15th and 16th century recipes
[Credit: British Library]

Figuring out the chemical reactions of the components that made writing on paper possible and last for hundreds of years was the aim of the Meridies Medieval History research group at the University of Cordoba. For months, this group has focused its work on these chemical reactions in collaboration with chemists at Nova University Lisbon.
This team, headed by University of Cordoba Medieval History Professor Ricardo Córdoba, carried out the duplication of five medieval inks, using each and every 15th and 16th century ingredient and method to do so. How did they do it? By analyzing handwritten recipes for making ink, painstakingly searching in several parts of the world such as the Bishop Chancellery in Braga, Portugal, where a 1464 recipe is kept, the School of Medicine Library in Montpellier, with another dated between 1469 and 1480, as well as the Historical Archive of Cordoba Province, dated 1474.
These five unpublished documents allowed for replicating the five inks. Pomegranate peels, galls used by plants for defense against parasites, vitriol, water, and gum arabic made from recipes using animal skins, are some of the ingredients that make up these inks and the ones that researchers mixed in the exact same quantity, proportion, temperature and method as indicated in the medieval recipes, and with which it was possible to replicate the exact same inks as the ones used six centuries ago.
The results of this collaborative research between historians and chemists were recently published in the journal Heritage Science. This research included translations of the texts and procedures outlined in the medieval recipes, the making of the inks following the step-by-step directions contained in the recipes, and the analysis of the chemical reactions of these ingredient combinations, with the aim of finding keys to conserving written heritage. By means of exact replication and analysis of inks used in the Middle Ages, researchers can determine which treatments historical documents should undergo in order to recover and improve their current condition and, above all, ensure that they will physically last longer.


Source: University of Córdoba [February 05, 2019]



TANN



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New Horizons’ Evocative Farewell Glance at Ultima Thule


NASA – New Horizons Mission patch.


February 8, 2019


Images Confirm the Kuiper Belt Object’s Highly Unusual, Flatter Shape




Video above: The Truly Odd Shape of Ultima Thule. Video Credits: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute/National Optical Astronomy Observatory.


An evocative new image sequence from NASA’s New Horizons spacecraft offers a departing view of the Kuiper Belt object (KBO) nicknamed Ultima Thule – the target of its New Year’s 2019 flyby and the most distant world ever explored.


These aren’t the last Ultima Thule images New Horizons will send back to Earth – in fact, many more are to come — but they are the final views New Horizons captured of the KBO (officially named 2014 MU69) as it raced away at over 31,000 miles per hour (50,000 kilometers per hour) on Jan. 1. The images were taken nearly 10 minutes after New Horizons crossed its closest approach point.


“This really is an incredible image sequence, taken by a spacecraft exploring a small world four billion miles away from Earth,” said mission Principal Investigator Alan Stern, of Southwest Research Institute. “Nothing quite like this has ever been captured in imagery.”



Image above: The Crescent View. Image Credits: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute/National Optical Astronomy Observatory.


The newly released images also contain important scientific information about the shape of Ultima Thule, which is turning out to be one of the major discoveries from the flyby.


The first close-up images of Ultima Thule – with its two distinct and, apparently, spherical segments – had observers calling it a “snowman.” However, more analysis of approach images and these new departure images have changed that view, in part by revealing an outline of the portion of the KBO that was not illuminated by the Sun, but could be “traced out” as it blocked the view to background stars.


Stringing 14 of these images into a short departure movie, New Horizons scientists can confirm that the two sections (or “lobes”) of Ultima Thule are not spherical. The larger lobe, nicknamed “Ultima,” more closely resembles a giant pancake and the smaller lobe, nicknamed “Thule,” is shaped like a dented walnut.



Image above: New Data, New View. Image Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.


“We had an impression of Ultima Thule based on the limited number of images returned in the days around the flyby, but seeing more data has significantly changed our view,” Stern said. “It would be closer to reality to say Ultima Thule’s shape is flatter, like a pancake. But more importantly, the new images are creating scientific puzzles about how such an object could even be formed. We’ve never seen something like this orbiting the Sun.”


The departure images were taken from a different angle than the approach photos and reveal complementary information on Ultima Thule’s shape. The central frame of the sequence was taken on Jan. 1 at 05:42:42 UT (12:42 a.m. EST), when New Horizons was 5,494 miles (8,862 kilometers) beyond Ultima Thule, and 4.1 billion miles (6.6 billion kilometers) from Earth. The object’s illuminated crescent is blurred in the individual frames because a relatively long exposure time was used during this rapid scan to boost the camera’s signal level – but the science team combined and processed the images to remove the blurring and sharpen the thin crescent.




Video above: New Data, New View (Animation). Video Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.


Many background stars are also seen in the individual images; watching which stars “blinked out” as the object passed in front them allowed scientists to outline the shape of both lobes, which could then be compared to a model assembled from analyzing pre-flyby images and ground-based telescope observations. “The shape model we have derived from all of the existing Ultima Thule imagery is remarkably consistent with what we have learned from the new crescent images,” says Simon Porter, a New Horizons co-investigator from the Southwest Research Institute, who leads the shape-modeling effort.


“While the very nature of a fast flyby in some ways limits how well we can determine the true shape of Ultima Thule, the new results clearly show that Ultima and Thule are much flatter than originally believed, and much flatter than expected,” added Hal Weaver, New Horizons project scientist from the Johns Hopkins Applied Physics Laboratory. “This will undoubtedly motivate new theories of planetesimal formation in the early solar system.”



Image above: Illustration of NASA’s New Horizons spacecraft encountering 2014 MU69 – nicknamed “Ultima Thule” – a Kuiper Belt object that orbits one billion miles beyond Pluto. New Horizons’ exploration of Ultima is the farthest space probe flyby in history. Image Credits: NASA/JHUAPL/SwRI.


The images in this sequence will be available on the New Horizons LORRI website this week. Raw images from the camera are posted to the site each Friday (link bellow).


Related links:


New Horizons LORRI website: http://pluto.jhuapl.edu/soc/UltimaThule-Encounter/


For more information on the New Horizons mission, visit: https://www.nasa.gov/newhorizons


Images (mentioned), Videos (mentioned), Text, Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute.


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Meteor Activity Outlook for February 9-15, 2019

This brilliant fireball was photographed by Jay Shaffer on January 31, 2018 at 10:55 UT, from the dark skies of New Mexico. © Jay Shaffer/Skylapser.com This event corresponds to AMS event #522-2019 https://www.amsmeteors.org/members/imo_view/event/2019/522

During this period the moon will reach its first quarter phase on Tuesday February 12th. At this time the moon will be located 90 degrees east of the sun and will set near 0100 local standard time (LST). This will allow the more active morning hours to be free of interfering moonlight. As the week progresses beyond Tuesday the waxing gibbous moon will set later, shrinking the window of opportunity to view under optimal conditions. Hourly meteor rates for evening observers this week is near 2 as seen from mid-northern latitudes (45N) and 3 as seen from tropical southern locations (25S). For morning observers the estimated total hourly rates should be near 11 as seen from mid-northern latitudes and 16 from the southern tropics. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Rates are slightly reduced during the evening hours due to moonlight. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.


The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning February 9/10 . These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies near the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located far below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.






Radiant Positions at 7:00pm Local Standard Time







Radiant Positions at 12:00am Local Standard Time







Radiant Positions at 5:00am Local Standard Time





These sources of meteoric activity are expected to be active this week.


The center of the large Anthelion (ANT) radiant is currently located at 10:16 (154) +11. This position lies in western Leo, 2 degrees southeast of the 1st magnitude star known as Regulus (alpha Leonis). Due to the large size of this radiant, Anthelion activity may also appear from Cancer, northwestern Hydra, and Sextans as well as Leo. This radiant is best placed near 0100 local standard time (LST), when it lies on the meridian and is located highest in the sky. Rates at this time should be near 2 per hour as seen from the northern hemisphere and 1 per hour from south of the equator. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.


The alpha Antliids (AAN) should be active from a radiant located near 11:01 (165) -13. This position actually lies in western Crater, 4 degrees northwest of the 3rd magnitude star known as nu Hydrae. I’m not certain how this stream was named as it the radiant lies a good 20 degrees north of the Antlia border. Perhaps when activity was first noticed from this source the radiant was incorrectly determined? This radiant is best placed near 0200 LST, when it lies on the meridian and is located highest in the sky. Rates are expected to be near 1 per hour no matter your location. With an entry velocity of 45 km/sec., the average meteor from this source would be of medium velocity.


The February Epsilon Virginids (FEV) were discovered by Kathryn Steakly & Dr. Peter Jenniskens using data from CAMS and SonotaCo. This shower is active from January 27-February 17, with maximum activity occurring on February 3rd. The radiant is currently located at 13:46 (207) +08, which places it in southwestern Bootes, 7 degrees northwest of the 4th magnitude star known as tau Virginis. These meteors would be best seen near 0400 LST when the radiant lies highest above the horizon. Rates are expected to be less than 1 per hour during this period. These meteors are equally well seen from either hemisphere. These meteors encounter the atmosphere at 63 km/sec., which would produce mostly swift meteors.


After studies of the IMO video database provided by cameras located in Australia, Sirko Molau has determined that two more of the Centaurid radiants belonging to the southern hemisphere summer Velid-Crux-Centaurus complex may be distinguished by visual observers. These positions differ from those listed in the IAUs Meteor Data Center so actual shower members may not line up perfectly with the positions given here. The lack of cameras and actual data from the southern hemisphere prevents us from provided better parameters for these far southern radiants.  The first of these radiants, the omega Centaurids (OCA) may be seen from February 12-15 with maximum occurring on the 14th. At maximum the radiant is predicted to be near 13:16 (199) -55. This position lies in southern Centaurus, 4 degrees southwest of the 2nd magnitude star known as Epsilon Centauri. The MDC position lies in the southern portion of the Centaurus between Pi Centauri and Gacrux (Gamma Crucis). These meteors are best seen near 0330 LST when the radiant lies highest above the horizon. Maximum rates are not known but expected to be less than 1 per hour as seen from the southern hemisphere. These meteors are not visible north of 35N latitude. They are best seen from the southern tropics where the radiant rises high into the sky and the summer nights are longer than they are at more southern locations. At 48 km/sec. the Omega Centaurids would produce meteors with average velocities.


The pi Hydrids (PIH) were discovered in Dr. Peter Jenniskens and mentioned in his book Meteor Showers and their Parent Comets. Studies of the IMO video database by Sirko Molau and Juergen Rendtel confirmed the existence of this shower. These meteors are active from February 4-15, which maximum activity occurring on the 6th. The radiant is currently located at 13:50 (208) -21. This area of the sky is located in extreme southeastern Virgo, 6 degrees northwest of the 3rd magnitude star known as pi Hydrae. These meteors are best seen near 0500 LST when the radiant lies highest above the horizon. Rates are expected to remain below 1, even at maximum activity. These meteors are visible over most of the Earth, with the southern hemisphere having slightly better viewing conditions. At 55 km/sec. the pi Hydrids would produce mostly swift meteors.


The 2nd of these weak Centaurid radiants are the theta Centaurids (TCN). This radiant is also active February 12-16 with maximum occurring on the 14th. This activity may actually be detected by observers situated at mid-northern latitudes as the position lies near 13:56 (209) -29. This position lies near the Centaurus-Hydra border, 4 degrees southwest of the 3rd magnitude star known as Pi Hydrae. The MDC position lies 11 degrees further south between the stars Theta and Nu Centauri. These meteors are best seen near 0415 LST when the radiant lies highest above the horizon. Maximum rates are not known but expected to be less than 1 per hour as seen from the southern hemisphere. Although this source is visible from most of the northern hemisphere, this radiant are best seen from the southern tropics where the radiant rises higher into the sky  At 65 km/sec. most of the Theta Centaurids would produce meteors with fast velocities.


The alpha Centaurids (ACE) are active from February 2-19, with maximum activity occurring on February 8. The radiant is currently located at 14:14 (213) -59. This position lies in southeastern Centaurus, 2 degrees northeast of the 1st magnitude star known as Hadar (beta Centauri). Due to the southern declination of this radiant, these meteors are not well seen in the northern hemisphere. Current rates are expected to be near 3 for those in the southern hemisphere and less than 1 for those located north of the equator. These meteors are best seen near 0500 LST when the radiant lies highest above the horizon. At 56 km/sec. the alpha Centaurids would produce mostly swift meteors.


As seen from the mid-northern hemisphere (45N) one would expect to see approximately 7 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 1 per hour. As seen from the tropical southern latitudes (25S), morning rates would also be near 10 per hour as seen from rural observing sites and 2 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Rates are slightly reduced during the evening hours due to moonlight.






















































































SHOWER DATE OF MAXIMUM ACTIVITY CELESTIAL POSITION ENTRY VELOCITY CULMINATION HOURLY RATE CLASS
RA (RA in Deg.) DEC Km/Sec Local Standard Time North-South
Anthelion (ANT) 10:16 (154) +11 30 01:00 2 – 1 II
alpha Antliids (AAN) Feb 01 11:01 (165) -13 45 02:00 <1 – <1 IV
February epsilon Virginids (FEV) Feb 03 13:46 (207) +08 64 04:00 <1 – <1 IV
omega Centaurids (OCA) Feb 14 13:16 (199) -55 48 05:00 <1 – <1 IV
pi Hydrids (PIH) Feb 06 13:50 (208) -21 55 06:00 1 – 2 IV
theta Centaurids (TCN) Feb 14 13:56 (209) -29 65 06:00 <1 – <1 IV
alpha Centaurids (ACE) Feb 08 14:14 (213) -59 56 06:00 1 – 3 II

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How does the Amazon rain forest cope with drought?

The Amazon rain forest isn’t necessarily a place that many would associate with a drought, yet prolonged dry spells are projected to become more prevalent and severe because of climate change. The question at hand is how these droughts are going to affect the rain forest, as it has a large influence on global climate and future warming.











How does the Amazon rain forest cope with drought?

Tapajós National Forest in Brazil [Credit: Michigan State University]



A study led by Marielle Smith, a research associate in Michigan State University’s forestry department, and Scott Stark, assistant professor of forestry, examines the Amazon’s response to droughts in order to better predict how forest growth and physiology will affect tree diversity and, ultimately, the planet’s climate.


Due to its combination of wet forest structure and a strong dry season, the Tapajós National Forest in Brazil may be a good indicator for climate change responses, which is what led researchers to the location.


To gather information and monitor the rainforest, researchers took a detailed view of its structure by walking the ground with a lidar instrument, a tool also used in autonomous vehicles to map terrain. The lidar produced information in two-dimensional slices that describe how leaf area is structured across heights and micro-environments varying in light, temperature and humidity.


“This is useful because the activity of a forest as a whole – its growth and exchanges of gas and energy with the atmosphere – is largely determined by how leaves are distributed in the mosaic of environments that the forest itself creates,” Smith said.


A total of 41 monthly surveys were conducted over the course of four years, between 2010 and 2017, and included three non-drought years and one El Niño drought year.


“Through the lidar lens, we surveyed the structure of an eastern Amazon forest over several years to see how it changed in response to seasonal water stress and a strong El Niño drought,” Smith said.


The research yielded surprising results.



Researchers found that the rainforest increased the amount of leaves in the highest canopy during dry seasons and drought, despite reports from previous studies that found big trees to be more vulnerable to drought.


Previous satellite lidar observations have shown that when leaf amounts in the upper canopy go up, the amounts in the lower canopy go down, and vice versa, over the seasonal cycle of the Amazon forest. This could be due to seasonal variation in the amount of shading inflicted on the lower canopy by the upper.


“Our higher-resolution data allowed us to divide the forest by both height and light environments, and revealed something more complex,” Smith said.


The expectation was that when the amount of leaves in tall trees increases during the dry season it gets shadier underneath, and smaller trees lose some of their leaves as a result. However, the data showed that’s not what happened. Instead, it was the small trees that were in open areas where shading was low and sunlight high – forest “gaps” – that lost leaves. Trees that were shaded, surprisingly, added leaf area at the same time as the tall trees. The trends were the same in response to drought.


“It is key to understand that dry periods are typically sunnier periods,” Smith said. “Tall trees that also have deeper roots, giving more access to water, may take advantage of the increased light and expand their crowns. Small trees with shallow roots may be hurt more by hot, sunny conditions and contract their crowns or die. Small trees in the shade, however, may take advantage of increased light in the cooler, more humid understory.”


These results show that a tree’s response to dry periods is dependent on environmental conditions imposed by the structure of the rainforest itself, the researchers said. The findings agree closely with emerging studies showing that short statured vegetation, particularly in hot, high light environments, is most impacted by water shortages.


At the same time, the research is helping build a picture of how canopy micro-environments, tree heights, seasonality and drought come together to determine which trees will win and lose under drier climates. This is crucial to understanding the future resilience of the Amazon to climate change, the researchers said.


The study is published in New Phytologist.


Author: Jessica Hanna | Source: Michigan State University [Febrary 06, 2019]



TANN



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