вторник, 4 декабря 2018 г.

Clear to Fly Fruit flies share around 60% of their genes with…


Clear to Fly


Fruit flies share around 60% of their genes with humans, so it’s not surprising that some aspects of our development are similar, too. Peaking inside a fly’s brain can reveal clues about own early nervous system, but there are challenges. This fly’s huge compound eyes normally contain coloured pigments which interfere with laser light used by powerful microscopes. But a new technique called ‘FlyClear’ sluices away the pigmentation, clearing the blocking chemicals but leaving the fly’s brain intact and transparent. Using gentle ultramicroscopy, tiny networks of neurons stretching behind the eyes to the brain are picked out, artificially coloured here in green. Applying these techniques to flies of different ages might reveal clues about how neurodegenerative diseases disrupt these networks – a vital step towards treatments.


Written by John Ankers



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First commercial satellite of Switzerland


ASTROCAST logo.


Dec 4, 2018



Spaceflight SSO-A lift off

The first commercial satellite created in Switzerland was launched Monday night on SpaceX rocket. The equivalent of 4 years of work for Astrocast, based at EPFL, launched yesterday by a SpaceX Falcon 9 rocket.



Falcon 9 spaceflight launches SSO-A & Falcon 9 first stage landing

3 … 2 … 1 … lift-off! For the first time, aboard the SpaceX Falcon9 rocket launched Monday from California, was a commercial satellite entirely created in Switzerland. The start-up that designed, built and will exploit it, celebrated on this occasion in small committee this major step, after several false hopes: the launch has been postponed four times by SpaceX for checks or weather concerns.


Swiss space distances itself from the debacle of S3


The soap opera of the company S3, based in Payerne, tainted the image of the Swiss space. “With the general public and non-specialized partners, we had to show that we were not at all in the same situation, explains Fabien Jordan. S3 had utopian goals, unrealistic, and committed early serious management mistakes. As a start-up, Astrocast has undergone a much more progressive development, aimed at ensuring its sustainability. “


Switzerland has already tasted the space


The Apollo 11 mission deployed an experiment on the solar wind at Moon and the astronauts were equipped with Omega watches, atomic clocks for satellites. Since 1992, Switzerland has an astronaut, Claude Nicollier. Material developed by the University of Bern also accompanied the first steps on the moon. But Switzerland also has several satellites to its credit. The SwissCube, developed at EPFL, was launched in 2009 thanks to the work of many researchers and students. Many of them are working today for Astrocast. In addition, systems to clean the Earth’s orbit of its many debris are currently being developed.


A constellation of nano-satellites


“It’s stressful, and very exciting at the same time,” says Fabien Jordan, CEO of Astrocast. After 4 years, it’s time to prove to investors and customers that it works, before you can move forward. “Indeed, the start-up does not stop there.



Astrocast cubesat’s constellation

If this demonstration mission works, a whole constellation of nano-satellites will be launched around the earth, to create a lowcost system of communication between machines. The network will serve, for example, to locate lost maritime containers, or to manage drinking water installations in developing countries.


The culmination of 4 years of work


The company has about a year to build a dozen of these “cube sat”, each as large as a shoebox and weighing nearly 4 kg. The entire assembly line is in an EPFL building. “A tight schedule is always a challenge, admits Fabien Jordan. In four years, we had to raise funds, gather talent, and develop and test all our systems. “



Astrocast 0.1, 0.2 satellite

For the team, it will take another day or so before hoping to hear the first “beep” of Kiwi life, a small name for the satellite, and be able to slash the champagne.


SpaceX can launches small satellites for a low cost: 40’000.- Sfr / 1 Kg, the total cost for this mission is 450’000.- Sfr (200’000 for the Astrocast satellite and 250’000 the SpaceX launch).


Related articles:


Spaceflight SSO-A: SmallSat Express successfully launched
https://orbiterchspacenews.blogspot.com/2018/12/spaceflight-sso-smallsat-express.html


EPFL software at the command of satellites
https://orbiterchspacenews.blogspot.com/2017/05/epfl-software-at-command-of-satellites.html


Cleaning up Earth’s orbit: A Swiss satellite tackles space debris
https://orbiterchspacenews.blogspot.com/2012/02/cleaning-up-earths-orbit-swiss.html


Swiss Space Systems: bankruptcy confirmed
https://orbiterchspacenews.blogspot.com/2017/01/swiss-space-systems-bankruptcy-confirmed.html


Related link:


Astrocast: https://www.astrocast.com/


SpaceX: https://www.spacex.com/


Images, Video, Text, Credits: Astrocast/SpaceX/SciNews/Günter Space Page/Orbiter.ch Aerospace/Roland Berga.


Best regards, Orbiter.chArchive link


SpaceX – Private Lunar & Martian Missions


SpaceX logo.


Dec. 4, 2018



STARSHIP-SUPER HEAVY Moon flyby

On September 17, 2018, SpaceX announced fashion innovator and globally recognized art curator Yusaku Maezawa will be the company’s first private passenger to fly around the Moon in 2023. To date, only 24 people have visited the Moon, with the last of them flying in 1972.



STARSHIP-SUPER HEAVY size

This first private lunar passenger flight, featuring a fly-by of the Moon as part of a weeklong mission, will help fund development of SpaceX’s Starship and Super Heavy Rocket (formerly known as BFR), an important step in enabling access for everyday people who dream of flying to space.



STARSHIP-SUPER HEAVY lift-off

“You want to wake up in the morning and think the future is going to be great – and that’s what being a spacefaring civilization is all about. It’s about believing in the future and thinking that the future will be better than the past. And I can’t think of anything more exciting than going out there and being among the stars.” — Elon Musk, SpaceX.


STARSHIP-SUPER HEAVY


SpaceX’s Starship and Super Heavy Rocket represent a fully reusable transportation system designed to service all Earth orbit needs as well as the Moon and Mars. This two-stage vehicle—composed of the Super Heavy Rocket (booster) and Starship (ship)—will eventually replace Falcon 9, Falcon Heavy and Dragon.



By creating a single system that can service a variety of markets, SpaceX can redirect resources from Falcon 9, Falcon Heavy and Dragon to the Starship-Super Heavy system—which is fundamental in making the system affordable.


Starship-Super Heavy Uses


An important question we have to answer is, “How do we pay for this system?” The answer lies in creating a single system that can support a variety of missions. SpaceX can then redirect resources from Falcon 9, Falcon Heavy and Dragon to this system.




STARSHIP-SUPER HEAVY

Satellites
SpaaceX’s Starship and Super Heavy Rocket are designed to deliver satellites to Earth orbit and beyond, at a lower marginal cost per launch than our current Falcon vehicles. With a 9 m diameter forward payload compartment, larger than any other current or planned fairing, Starship creates possibilities for new missions, including space telescopes even larger than the James Webb.



STARSHIP-SUPER HEAVY first stage separation

Space Station Missions


Starship can deliver both cargo and people to and from the International Space Station. Starship’s pressurized forward payload volume is greater than 1,000 m3, enhancing utilization capacity for in-space activities. The aft cargo containers can also host a variety of payloads.


Interplanetary Transport



SpaceX Moon Base Alpha

Building Moon bases and Mars cities will require affordable delivery of significant quantities of cargo and people. The fully reusable Starship|Super Heavy system uses in-space propellant transfer to enable the delivery of over 100 t of useful mass to the surface of the Moon or Mars. This system is designed to ultimately carry as many as 100 people on long-duration, interplanetary flights.


Missions to Mars



SpaceX Mars Base

 
Our aspirational goal is to send our first cargo mission to Mars in 2022. The objectives for the first mission will be to confirm water resources, identify hazards, and put in place initial power, mining, and life support infrastructure.



Making Life Multiplanetary

A second mission, with both cargo and crew, is targeted for 2024, with primary objectives of building a propellant depot and preparing for future crew flights. The ships from these initial missions will also serve as the beginnings of the first Mars base, from which we can build a thriving city and eventually a self-sustaining civilization on Mars.



Mars colonization

Mars Entry


Starship will enter the Mars atmosphere at 7.5 kilometers per second and decelerate aerodynamically. The vehicle’s heat shield is designed to withstand multiple entries, but given that the vehicle is coming into the Mars atmosphere so hot, we still expect to see some ablation of the heat shield (similar to wear and tear on a brake pad).



 Mars landing

Earth to Earth Transportation


With Starship and the Super Heavy Rocket, most of what people consider to be long distance trips would be completed in less than half an hour. In addition to vastly increased speed, one great benefit about traveling in space, outside of Earth’s atmosphere, is the lack of friction as well as turbulence and weather. Consider how much time we currently spend traveling from one place to another. Now imagine most journeys taking less than 30 minutes, with access to anywhere in the world in an hour or less.


For more information about SpaceX, visit: SpaceX: https://www.spacex.com/


Images, Videos, Text, Credit: SpaceX.


Greetings, Orbiter.chArchive link


Millook Haven Beach, England…


Millook Haven Beach, England http://www.geologypage.com/2018/12/millook-haven-beach-england.html


Double Trouble: A White Dwarf Surprises Astronomers



ASASSN-16oh

Illustration Credit NASA/CXC/M.Weiss






Astronomers have detected a bright X-ray outburst from a star in the Small Magellanic Cloud, a nearby galaxy almost 200,000 light years from Earth. A combination of X-ray and optical data indicate that the source of this radiation is a white dwarf star that may be the fastest-growing white dwarf ever observed.


In several billion years, our Sun will run out of most of its nuclear fuel and shrink down to a much smaller, fainter “white dwarf” star about the size of Earth. Because a mass equivalent to that of the Sun is packed into such a small volume, the gravity on the surface of a white dwarf is several hundred thousand times that of Earth.


Unlike our Sun, most stars including white dwarfs, do not exist in isolation, but instead are part of pairs called “binary systems.” If the stars are close enough, the gravity of the white dwarf can pull matter away from its companion. 


A new study based on observations with NASA’s Chandra X-ray Observatory and Neil Gehrels Swift Observatory has reported the discovery of distinctive X-ray emission from a binary system containing a white dwarf called ASASSN-16oh. The discovery involves the detection of low-energy — what astronomers refer to as “soft” — X-rays, produced by gas at temperatures of several hundred thousand degrees. In contrast, higher-energy X-rays reveal phenomena at temperatures of tens of millions of degrees. The X-ray emission from ASASSN-16oh is much brighter than the soft X-rays produced by the atmospheres of normal stars, placing it in the special category of a supersoft X-ray source. 


For years, astronomers have thought that supersoft X-ray emission from white dwarf stars is produced by nuclear fusion in a hot, dense layer of hydrogen and helium nuclei. This volatile material accumulated from the infall of matter from the companion star onto the surface of the white dwarf, and led to a nuclear fusion explosion much like a hydrogen bomb. 


However, ASASSN-16oh shows there is more to the story. This binary was first discovered by the All-Sky Automated Survey for Supernovae (ASASSN), a collection of about 20 optical telescopes distributed around the globe to automatically survey the entire sky every night for supernovas and other transient events. Astronomers then used Chandra and Swift to detect the supersoft X-ray emission. 


“In the past, the supersoft sources have all been associated with nuclear fusion on the surface of white dwarfs,” said lead author Tom Maccarone, a professor in the Texas Tech Department of Physics & Astronomy who led the new paper that appears in the December 3rd issue of Nature Astronomy.


If nuclear fusion is the cause of the supersoft X-rays from ASASSN-16oh then it should begin with an explosion and the emission should come from the entire surface of the white dwarf. However, the optical light does not increase quickly enough to be caused by an explosion and the Chandra data show that the emission is coming from a region smaller than the surface of the white dwarf. The source is also a hundred times fainter in optical light than white dwarfs known to be undergoing fusion on their surface. These observations, plus the lack of evidence for gas flowing away from the white dwarf, provide strong arguments against fusion having taken place on the white dwarf.


Because none of the signs of nuclear fusion are present, the authors present a different scenario. As with the fusion explanation the white dwarf is pulling gas away from a companion star, a red giant. In a process called accretion, the gas is pulled onto a large disk surrounding the white dwarf and becomes hotter as it spirals toward the white dwarf, as shown in our illustration. The gas then falls onto the white dwarf, producing X-rays along a belt where the disk meets the star. The rate of inflow of matter through the disk varies by a large amount. When the material starts flowing more quickly, the X-ray brightness of the system becomes much higher.


“The transfer of mass is happening at a higher rate than in any system we’ve caught in the past,” added Maccarone.


If the white dwarf keeps gaining mass it may reach a mass limit and destroy itself in a Type Ia supernova explosion, a type of event used to discover that the expansion of the universe is accelerating. The team’s analysis suggests that the white dwarf is already unusually massive so ASASSN-16oh may be relatively close — in astronomical terms — to exploding as a supernova.


“Our result contradicts a decades-long consensus about how supersoft X-ray emission from white dwarfs is produced,” said co-author Thomas Nelson from the University of Pittsburgh. “We now know that the X-ray emission can be made in two different ways: by nuclear fusion or by the accretion of matter from a companion.”


Also involved in the study were scientists from Texas A&M University, NASA Goddard Space Flight Center, University of Southampton, University of the Free State in the Republic of South Africa, the South African Astronomical Observatory, Michigan State University, State University of New Jersey, Warsaw University Observatory, Ohio State University and the University of Warwick.


NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.



Fast Facts for ASASSN-16oh:

Category: White Dwarfs & Planetary Nebulas
Coordinates (J2000): RA 1h 57m 43s | Dec -73° 37´ 32.5″
Constellation: Tucana
Observation Date: December 28, 2016
Observation Time: 13 hours 36 minutes
Obs. ID: 19983
Instrument: HRC
References: Maccarone, T et al, 2018, Nature Astronomy (published Dec 3rd)
Distance Estimate: About 200,000 light years






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Polar Vastness


Polar Vastness


HiPOD (4 December 2018): Chocolate Sundae, Anyone?   – These…



HiPOD (4 December 2018): Chocolate Sundae, Anyone?


   – These lovely dunes and their tantalizing frost are inside the massive Proctor Crater. (Alt: 252 km. Black and white is less than 5 km across; enhanced color is less than 1 km.)


NASA/JPL/University of Arizona


On the trail of the Proto-Uralic speakers (work in progress)

Historical linguists have long posited that Fennoscandia was a busy contact zone between early Germanic and Uralic languages. The first ancient DNA samples from what is now Finland have corroborated their inferences, by showing that during the Iron Age the western part of the country was inhabited by a genetically heterogeneous population closely related to both the Uralic-speaking Saami and Germanic-speaking southern Scandinavians.
The samples were sequenced and analyzed by two different teams of researches, and their findings published recently in Lamnidis et al. and Sikora et al. (see here and here, respectively).
This is how most of these ancients, whose remains were excavated from the Levanluhta burial site dated to 300–800 CE, behave in a Principal Component Analysis (PCA) based on my Global25 data. Levanluhta_IA are the Saami-related samples, while Levanluhta_IA_o is an Scandinavian-like outlier. Baltic_IA is an early Iron Age individual from what is now Lithuania from the recent Damgaard et al. paper (see here). Note the accuracy of the Global25 data in pinpointing their genetic affinities and also the trajectory of the Levanluhta_IA cluster, which seems to be “pulling” towards Levanluhta_IA_o.



The Saami and Levanluhta_IA are clear outliers from the main Northern European cluster. There are two reasons for this: excess East Asian/Siberian-related ancestry and Saami-specific genetic drift. However, this eastern admixture and genetic drift are shared in varying degrees by other North European populations, especially those that also speak Uralic languages, and this is why they appear to be “pulling” towards the Saami/Levanluhta_IA clusters in my PCA. Thus, what this suggests is that the expansion of Uralic languages across Northeastern Europe was intimately linked with the spread of Siberian-related ancestry into the region.
This idea has been around for a long time and is now becoming even more widely accepted (see here). However, Lamnidis et al. also featured samples from a likely pre-Uralic (1523±87 calBCE) burial site at Bolshoy Oleni Ostrov in the Kola Peninsula, present-day northern Russia, and, perhaps surprisingly, found that they showed even more Siberian-related ancestry than Levanluhta_IA. So what’s going on?
I’m confident that this discrepancy can be explained by multiple waves of migrations from the east into Northeastern Europe, possibly before, during and after the time of the people buried at Bolshoy Oleni Ostrov, by pre-Uralic, para-Uralic and/or Proto-Uralic-speaking populations.
Consider the following qpAdm output, in which Levanluhta_IA is just barely modeled successfully as a two-way mixture between Levanluhta_IA_o and Bolshoy_Oleni_Ostrov. The statistical fit improves significantly with the addition of Glazkovo_EBA as a third mixture source. This is an ancient population from near Lake Baikal dated to 4597-3726 BC from the aforementioned Damgaard et al. paper.



Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.468±0.036
Levanluhta_IA_o 0.532±0.036
chisq 19.129
tail prob 0.0854706
Full output
Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.241±0.092
Glazkovo_EBA 0.162±0.059
Levanluhta_IA_o 0.597±0.046
chisq 7.756
tail prob 0.734966
Full output



For the sake of being complete, I also tested whether Levanluhta_IA_o could be substituted by other similar ancient samples from the neighborhood, including those associated with the Battle-Axe and Corded Ware cultures. There’s not much to report; qpAdm returned poor statistical fits and/or implausible ancestry proportions (for the full output from my runs, see here). Baltic_IA did produce a statistically sound model, but with excess Glazkovo_EBA-related ancestry. I also had to drop Bolshoy_Oleni_Ostrov from the analysis to make things work, which suggests to me that the result shouldn’t be taken too literally.



Levanluhta_IA
Baltic_IA 0.677±0.034
Glazkovo_EBA 0.323±0.034
chisq 8.547
tail prob 0.741095
Full output



So as far as I can see, the western ancestry in Levanluhta_IA is likely to be mostly of Germanic origin, and thus Indo-European, meaning that it’s logical to look east, perhaps far to the east, for the source of its Uralic ancestry. This might seem like a complicated and uncertain task, considering that Levanluhta_IA could well be at least a thousand years younger than the first entry of Uralic speakers into Fennoscandia. However, take a look what happens when I substitute Glazkovo_EBA with a variety of Uralic-speaking populations from around the Ural Mountains, which is where the Proto-Uralic homeland is generally considered to have been located.



Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.210±0.091
Khanty 0.283±0.090
Levanluhta_IA_o 0.507±0.035
chisq 7.007
tail prob 0.798532
Full output
Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.193±0.098
Levanluhta_IA_o 0.495±0.035
Mansi 0.312±0.100
chisq 7.884
tail prob 0.7237
Full output
Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.300±0.065
Levanluhta_IA_o 0.337±0.072
Mari 0.363±0.121
chisq 8.393
tail prob 0.677705
Full output
Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.238±0.084
Levanluhta_IA_o 0.553±0.036
Nenets 0.209±0.067
chisq 7.210
tail prob 0.78181
Full output
Levanluhta_IA
Bolshoy_Oleni_Ostrov 0.302±0.069
Levanluhta_IA_o 0.324±0.081
Udmurt 0.373±0.135
chisq 9.195
tail prob 0.60393
Full output



All of these models look great, and easily rival the best model with Glazkovo_EBA. Moreover, they make good sense in terms of linguistics. The only problem is that they’re anachronistic, because the Uralic-speaking reference populations are younger than Levanluhta_IA. So I can’t be certain that they reflect reality without corroboration from ancient DNA. It might turn out, for instance, that an Glazkovo_EBA-like population was already present somewhere deep in Europe before or during the time of Bolshoy_Oleni_Ostrov, while no such population existed around the Ural Mountains until the time of Levanluhta_IA.
By the way, it might be important to note that the present-day Finnish samples in my dataset can’t be modeled as a mixture between Levanluhta_IA and Levanluhta_IA_o. But they can be modeled as a mixture between Baltic_IA and Levanluhta_IA. I don’t know which part of Finland they’re from exactly; probably all over the place, so it’d be useful to test regional Finnish populations to see how they behave in such models. Of course, Finns aren’t Saamic speakers, they’re Finnic speakers, and they’re probably the result of a more recent Uralic expansion into Fennoscandia than the one that gave rise to the Saami.



Finnish
Baltic_IA 0.671±0.076
Levanluhta_IA 0.329±0.076
chisq 14.114
tail prob 0.293508
Full output



Damgaard et al. didn’t report the Y-haplogroup for Baltic_IA, but the word round the campfire is that this individual belonged to N1c, which is today the most common Y-haplogroup among Uralic speakers. Obviously, we need a lot more ancient DNA to sort all of this out, but things are already looking pretty much as expected. Stay tuned for new posts in this series following the publication of more ancient DNA relevant to this fascinating topic.
See also…
The Uralic cline in the Global25
Late PIE ground zero now obvious; location of PIE homeland still uncertain, but…
Genetic and linguistic structure across space and time in Northern Europe

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Noseless Gene This scan shows a child who was born without a…


Noseless Gene



This scan shows a child who was born without a nose – arhinia. It’s a congenital condition that’s extremely rare: only around 80 cases worldwide have been reported in the last century. And scientists have been at a loss to understand its cause. But now a genetic analysis of 40 arhinia patients and their families has identified a causative mutation carried by 84 percent of affected individuals. Interestingly, the mutation affects a gene previously associated with a far more common condition: facioscapulohumeral muscular dystrophy Type 2 (FSHD2) – so named for its tendency to affect muscles of the face (facio), back (scapulo) and upper arms (humeral). How mutations to the same gene can cause such disparate conditions is, as yet, a mystery, but the findings suggest that arhina patients may be at risk of developing FSHD2, while FSHD2 patients may be at risk of parenting babies with ahrinia.


Written by Ruth Williams




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Scenes from Viking Jorvik, York, 25.11.18.










Scenes from Viking Jorvik, York, 25.11.18.


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2018 December 4 Rocket Launch between Mountains Image Credit…


2018 December 4


Rocket Launch between Mountains
Image Credit & Copyright: Yudong Jiang


Explanation: What’s happening between those mountains? A rocket is being launched to space. Specifically, a Long March 3B Carrier Rocket was launched from Xichang Satellite Launch Center in Sichuan Province in China about two week ago. The rocket lifted two navigation satellites to about 2,000 kilometers above the Earth’s surface, well above the orbit of the International Space Station, but well below the orbit of geostationary satellites. China’s Chang’e 3 mission that landed the robotic Yutu rover on the Moon was launched from Xichang in 2013. The featured image was taken about 10 kilometers from the launch site and is actually a composite of nine exposures, including a separate background image.


∞ Source: apod.nasa.gov/apod/ap181204.html


Gold | #Geology #GeologyPage #Mineral Locality: Colorado Quartz…


Gold | #Geology #GeologyPage #Mineral


Locality: Colorado Quartz Mine, Whitlock District, Mariposa Co., California, USA


Size: 9.9 x 2 x 0.7


Photo Copyright © Saphira Minerals


Geology Page

www.geologypage.com

https://www.instagram.com/p/Bq9GXjQFySW/?utm_source=ig_tumblr_share&igshid=w3dq9a0el45h


Paulingite | #Geology #GeologyPage #Mineral Locality: Vinarice,…


Paulingite | #Geology #GeologyPage #Mineral


Locality: Vinarice, Kladno, Bohemia, Czech Republic

Size: 2.6 × 2.4 × 2 cm


Photo Copyright © Systematica /e-rocks.com


Geology Page

www.geologypage.com

https://www.instagram.com/p/Bq9JoEGlZYh/?utm_source=ig_tumblr_share&igshid=80jhbs8pbqc


Anglo-Saxon and Norse inspired stonework at the ‘Vikings:…







Anglo-Saxon and Norse inspired stonework at the ‘Vikings: Rediscover The Legend’ exhibition at The Yorkshire Museum, York, 30.5.17. The stonework features various patterns and motifs plus a scene from the Volsunga Saga (Image 4).


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Neanderthal and Stone Age mannequins and reconstructed Bronze…





Neanderthal and Stone Age mannequins and reconstructed Bronze Age burial, The Museum of East Riding, 2.6.17.


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Decorated Bronze Dagger and Flat Bronze Axe, both 1700 to 1500…



Decorated Bronze Dagger and Flat Bronze Axe, both 1700 to 1500 BCE, The British Museum, August 2017. The dagger is from the River Thames whilst the axe is from Country Antrim. Daggers with metal hilts are very unusual in Britain and this one is particularly ornate. It is thought to have been an early example of a watery votive offering.


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The total solar eclipse is coming! Here’s your chance to ask an…


The total solar eclipse is coming! Here’s your chance to ask an eclipse scientist your questions!


Have questions about the upcoming total solar eclipse on August 21? Join our Tumblr Answer Time session on Thursday, August 17 from 3:00 – 4:00 p.m. EDT/12:00 – 1:00 p.m. PDT. here on NASA’s Tumblr, where space physics researcher Alexa Halford will answer them. Make sure to ask your questions now by visiting: https://nasa.tumblr.com/ask!


See all the #AnswerTime questions here: https://nasa.tumblr.com/tagged/answertime


Alexa Halford is a space physics researcher at our Goddard Space Flight Center and Dartmouth College. She started researching waves in Earth’s magnetosphere as an undergraduate at Augsburg College with Mark Engebretson using ground based magnetometers in the Arctic and Antarctic. She moved away from waves to focus on geomagnetic storms and substorms during her masters at the University of Colorado Boulder with Dan Baker but returned once more to waves with her PhD at University of Newcastle NSW Australia. Her PhD thesis was on Electromagnetic Ion Cyclotron (EMIC) waves during the CRRES mission and their relationship to the plasmasphere and radiation belts.


She is member of the scientific team for a NASA-funded scientific balloon experiment project called BARREL (Balloon Array for RBSP Relativistic Electron Losses) where she looks at the population of particles lost due to these interactions. She is now currently a contractor at NASA Goddard continuing work the BARREL and NASA Van Allen Probes satellite missions.


To get more information about the eclipse, visit: https://eclipse2017.nasa.gov/


Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com


Mars New Home ‘a Large Sandbox’


NASA – InSight Mission logo.


Dec. 3, 2018



Image above: NASA’s InSight spacecraft flipped open the lens cover on its Instrument Context Camera (ICC) on Nov. 30, 2018, and captured this view of Mars. Located below the deck of the InSight lander, the ICC has a fisheye view, creating a curved horizon. Some clumps of dust are still visible on the camera’s lens. One of the spacecraft’s footpads can be seen in the lower right corner. The seismometer’s tether box is in the upper left corner. Image Credits: NASA/JPL-Caltech.


With InSight safely on the surface of Mars, the mission team at NASA’s Jet Propulsion Laboratory in Pasadena, California, is busy learning more about the spacecraft’s landing site. They knew when InSight landed on Nov. 26 that the spacecraft had touched down on target, a lava plain named Elysium Planitia. Now they’ve determined that the vehicle sits slightly tilted (about 4 degrees) in a shallow dust- and sand-filled impact crater known as a “hollow.” InSight has been engineered to operate on a surface with an inclination up to 15 degrees.


“The science team had been hoping to land in a sandy area with few rocks since we chose the landing site, so we couldn’t be happier,” said InSight project manager Tom Hoffman of JPL. “There are no landing pads or runways on Mars, so coming down in an area that is basically a large sandbox without any large rocks should make instrument deployment easier and provide a great place for our mole to start burrowing.”


Rockiness and slope grade factor into landing safety and are also important in determining whether InSight can succeed in its mission after landing. Rocks and slopes could affect InSight’s ability to place its heat-flow probe — also known as “the mole,” or HP3 — and ultra-sensitive seismometer, known as SEIS, on the surface of Mars.



Animation above: As visible in this two-frame set of images, NASA’s InSight spacecraft unlatched its robotic arm on Nov. 27, 2018, the day after it landed on Mars. Animation Credits: NASA/JPL-Caltech.


Touching down on an overly steep slope in the wrong direction could also have jeopardized the spacecraft’s ability to get adequate power output from its two solar arrays, while landing beside a large rock could have prevented InSight from being able to open one of those arrays. In fact, both arrays fully deployed shortly after landing.


The InSight science team’s preliminary assessment of the photographs taken so far of the landing area suggests the area in the immediate vicinity of the lander is populated by only a few rocks. Higher-resolution images are expected to begin arriving over the coming days, after InSight releases the clear-plastic dust covers that kept the optics of the spacecraft’s two cameras safe during landing.


“We are looking forward to higher-definition pictures to confirm this preliminary assessment,” said JPL’s Bruce Banerdt, principal investigator of InSight. “If these few images — with resolution-reducing dust covers on — are accurate, it bodes well for both instrument deployment and the mole penetration of our subsurface heat-flow experiment.” 


Once sites on the Martian surface have been carefully selected for the two main instruments, the team will unstow and begin initial testing of the mechanical arm that will place them there.


Data downlinked from the lander also indicate that during its first full day on Mars, the solar-powered InSight spacecraft generated more electrical power than any previous vehicle on the surface of Mars.


“It is great to get our first ‘off-world record’ on our very first full day on Mars,” said Hoffman. “But even better than the achievement of generating more electricity than any mission before us is what it represents for performing our upcoming engineering tasks. The 4,588 watt-hours we produced during sol 1 means we currently have more than enough juice to perform these tasks and move forward with our science mission.”



Animation Credits: NASA/JPL-Caltech

Launched from Vandenberg Air Force Base in California May 5, InSight will operate on the surface for one Martian year, plus 40 Martian days, or sols — the equivalent of nearly two Earth years. InSight will study the deep interior of Mars to learn how all celestial bodies with rocky surfaces, including Earth and the Moon, formed.


JPL manages InSight for NASA’s Science Mission Directorate. InSight is part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama.


A number of European partners, including France’s Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR), are supporting the InSight mission. CNES, and the Institut de Physique du Globe de Paris (IPGP), provided the SEIS instrument, with significant contributions from the Max Planck Institute for Solar System Research (MPS) in Germany, the Swiss Institute of Technology (ETH) in Switzerland, Imperial College and Oxford University in the United Kingdom, and JPL. DLR provided the HP3 instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología (CAB) supplied the wind sensors.


For more information about InSight, visit: https://www.nasa.gov/insight/


For more information about NASA’s Mars missions, go to: https://www.nasa.gov/mars


Image (mentioned), Animations (mentioned), Text, Credits: NASA/Dwayne Brown/JoAnna Wendel/Tony Greicius/JPL/DC Agle.


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