Global Climate Change | Source of NASA Data

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Global Climate Change:  An Excellent Source of NASA Data

Welcome to the Global Climate Change data visualization tool on MY NASA DATA. This page links you to a powerful data viewer that will allow you to examine all of the key climate change indicators that have been identified on the Global Climate Change website. You will be able to view these indicators on the Live Access Server (LAS) that we’ve configured for you to view global and local data pertaining to these key areas of interest. For all of the parameters below, after clicking on their respective links, please click on “Choose Dataset” button on the upper left hand side of the LAS page and then click on the cross directly to the left of the indicator that you’d like to view, for some browsers, the Choose Dataset dialogue box will automatically appear. We’ve provided a description of each parameter that is currently available. If you have and questions or issues with the LAS please email the MY NASA DATA support team.

Ancient European genomes reveal jumbled ancestry

Mysterious peoples from the north and Middle Easterners joined prehistoric locals.

• Ewen Callaway
• 02 January 2014

 

De Agostini Picture Library/Getty Images

Europe was inhabited by hunter-gatherers before migrations from the Middle East brought agriculture to the continent.

Newly released genome sequences from almost a dozen early human inhabitants of Europe suggest that the continent was once a melting pot in which brown-eyed farmers encountered blue-eyed hunter-gatherers.

Present-day Europeans, the latest work shows, trace their ancestry to three groups in various combinations: hunter-gatherers, some of them blue-eyed, who arrived from Africa more than 40,000 years ago; Middle Eastern farmers who migrated west much more recently; and a novel, more mysterious population whose range probably spanned northern Europe and Siberia.
That conclusion comes from the genomes of 8,000-year-old hunter-gatherers — one man from Luxembourg and seven individuals from Sweden — as well as the genome of a 7,500-year-old woman from Germany. The analysis, led by Johannes Krause of the University of Tübingen, Germany, and David Reich of Harvard Medical School in Boston, Massachusetts, was posted on the biology preprint website bioRxiv.org on 23 December 2013¹. The results have not yet been published in a peer-reviewed journal.

A second team, led by Carles Lalueza-Fox at the University Pompea Fabra in Barcelona, Spain, will soon publish the genome of a 7,000-year-old hunter-gatherer from northwest Spain, the palaeogenomicist said at a recent talk. In 2012, his team released preliminary genomic data from the same sample, suggesting that this hunter-gatherer bore little relationship to modern Spaniards². The two papers describe what are thought to be the oldest human genomes from Europe found so far.

Milk or grain

The new studies sketch a portrait of early Europeans based on variations in DNA that are known to be linked to traits in modern humans.

The authors' gene sequencing suggests that the individuals from Luxembourg and Spain, although dark-skinned, probably had blue eyes and belonged to groups known to be hunter-gatherers. The German woman, meanwhile, had brown eyes and lighter skin, and was related to Middle Eastern groups known to have developed farming. However, both the Luxembourg hunter-gatherer and the German farmer had multiple copies of a gene that breaks down starches in saliva, a feature that has been proposed to be an adaptation to the grain-laden diets characteristic of agricultural life. On the other hand, neither of them had the ability to digest the sugar lactose, found in milk, a trait that emerged in the Middle East after the domestication of cattle and that later spread to Europe.

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The work also adds a few twists to the prehistory of Europe. Previous archaeological and genetic studies suggested that most of today’s Europeans are descended from Middle Eastern farmers who interbred with local hunter-gatherers in some regions and displaced these early residents in others. Krause’s team concludes that a third population contributed to the gene pool of contemporary Europeans.

This group, which the authors call ancient northern Eurasians, may have lived at high latitudes between Europe and Siberia until a few thousand years ago. Traces of this population were also detected in the genome of a 24,000 year-old Siberian child. Published online last month, the boy’s genome suggests that northern Eurasians interbred with the ancestors of Native Americans as well as with Europeans³.

Diverse migrations

A comparison of the new data with genetic sequencing of present-day individuals shows that the current residents of various European countries are composites of these three groups. Scots and Estonians, for instance, have more northern Eurasian ancestry than any other modern European population sampled, whereas Sardinians are more closely related to Eastern farmers than are other Europeans.

The new European ancient genomes also hint at early human forays out of Africa. Middle Eastern farmers, Krause’s team discovered, split off from African ancestors earlier than did European and Asian groups. One possible explanation for this pattern is that the farmers are descended from humans who inhabited 100,000–120,000-year-old settlements in Israel and the Arabian Peninsula.

Many researchers assumed that these sites represented failed migrations out of Africa, because other evidence suggested that humans left Africa less than 100,000 years ago.
“I don’t think anybody saw that coming,” says Eske Willerslev, a palaeogeneticist at the University of Copenhagen. But he says that the population’s existence will be tough to prove conclusively. “It’s super interesting — if it’s correct,” Willerlsev adds.

“What would be really nice is to find some individual that is a direct observation of this population,” says Pontus Skogland, an evolutionary geneticist at Uppsala University in Sweden. Ancient DNA does not last long in hot climates, and so finding DNA from this population in the Middle East may require technological advances, as well as a bit of luck.

Lalueza-Fox declined to discuss his team’s work, but he cautions against making too many assumptions about the peopling of Europe using just a handful of ancient genomes from a single time period. “It’s going to be lots of different migrations and movements,” he says. “There’s going to be plenty of room for investigation in the next few years.”

Journal name:  Nature

DOI:  doi:10.1038/nature.2014.14456

New Mission Concepts for SLS With Use of Large Upper Stage

By Leonidas Papadopoulos

David Strumfels:  I have been down on the SLS, because I thought companies like SpaceX were getting closer to heavy/manned launchers sooner and probably cheaper.  A rocket like the close to testing Falcon Heavy will not have the capabilities of the SLS, but two might and still save over the SLS (in $$;  logistics in multiple coordinated launches will make it more complicated, erasing the savings); furthermore, SpaceX can make the existing Falcon Heavy and increase their capacities considerably (as they have been doing with their Falcon series in general) on a modest budget and time scale.

This article makes me wobble on my stance, however.  (It certainly makes me pant).  Now that missions are being proposed for it, I start to see the advantages of having this kind of ultra-heavy lift capacity, and the plans increasing this capacity strengthen those advantages.  Once it's ready, probably the Falcon series will probably never catch up; and I doubt the company has serious plans to do so.  Now.  So, I'm starting to become a rooter.  Or many it's just "rocket-envy."

New Mission Concepts for SLS With Use of Large Upper Stage

 

Boeing recently released a proposal for a new upper stage for the SLS Block I configuration that would enable the launch of even heavier payloads to deep-space destinations. Image Credit: NASA

Boeing recently released a set of proposals for new missions beyond low-Earth orbit for NASA’s Space Launch System, or SLS, utilising a newly designed Upper Stage.

The SLS is NASA’s next generation heavy-lift launch vehicle (HLV), which is on schedule to make its inaugural unmanned test flight in 2017. It will be used for launching the Orion Multi-Purpose Crew Vehicle, or MPCV, the space agency’s next manned spacecraft currently under construction, to deep-space destinations such as the Moon and Mars—a capability that had been lost with the cancellation of the Apollo lunar missions more than 40 years ago.

An artist rendering of the various configurations of NASA’s Space Launch System. Image Caption/Credit: NASA

Although the first two launches of the SLS in 2017 and 2021 respectively are designed to be test flights of the initial Block I configuration capable of delivering 70 metric tons to low-Earth orbit (LEO), NASA is designing the heavy launch system to be evolvable, with the final Block II configuration having a payload capacity of 130 metric tons to LEO—rivaling the capability of the Saturn V rocket that sent humans to the Moon during the 1960s and ’70s.

As reported at the NASA Spaceflight.com website, Boeing, which is the prime contractor for designing and building the SLS’s core and upper stages, recently presented its proposal for a new Large Upper Stage, or LUS, for use on the SLS, which would enable new missions to low-Earth orbit and beyond.

The currently designed upper stage for the Block I version of SLS is an Interim Cryogenic Propulsion Stage (ICPS), also known as the Delta Cryogenic Second Stage, or DCSS. This is the same upper stage used on the Delta IV rocket, and it employs a single RL-10B2 engine developed by Pratt & Whitney. Although the ICPS would boost a 70-metric-ton payload to LEO in the SLS Block I version, Boeing’s proposal for the LUS would significantly advance this capability to more than 90 metric tons, allowing for even more ambitious deep-space missions. “A new 8.4m Large Upper Stage (LUS), as a follow on to the interim Cryogenic Propulsion Stage (ICPS), can provide significant increases in SLS payload injection capability,” notes the company in its presentation.

An alternate concept of placing a human outpost to the Earth-Moon L2 point with the SLS is Skylab II, proposed by a team of engineers working with the Advanced Concepts Office at NASA’s Marshall Space Flight Center. Image Credit: NASA

“Someone reminded me that, up until the last two modules were put up on the ISS (via Shuttle), Skylab had more crew volume,” says Jim Crocker, Vice President and General Manager, Civil Space, Lockheed Martin Space Systems Co. “Skylab was done with one Saturn V. Sometimes it requires re-thinking of what you’re doing.”

These new mission concepts studied by Boeing fall into four main categories: LEO destinations, cislunar and lunar missions, Mars and Outer Solar System destinations.

One of the payloads that could take advantage of the SLS’s LEO payload capability, according to the Boeing study, is Bigelow Aerospace’s proposed BA 2100 inflatable habitat. Bigelow Aerospace is best known for its innovative and ambitious work on designing and launching inflatable modules in orbit, based on NASA’s TransHab technology. The private company has already launched two experimental modules in low-Earth orbit, Genesis I and II in 2006 and 2007 respectively. It is already planning to send a Bigelow Expandable Activity Module, or BEAM, on the International Space Station in 2015 and plans to develop  the first privately built space station called Bigelow Commercial Space Station, constructed from several BA 330 modules that are currently under development.

The large Bigelow BA 2100 module could fit inside the 8.4m payload fairing of the proposed LUS upper stage. Image Credit: NASASpaceFlight.com

Yet the company revealed even more ambitious plans in the 2010 International Symposium for Private and Commercial Spaceflight held in Las Cruces, N.M., with the unveiling of the BA 2100, or Olympus module concept. As the number on its name implies, BA 2100 would feature a living area of 2,100 cubic meters of volume, completely dwarfing the smaller BA 330. This enormous habitat would have a calculated mass of 70 to 100 metric tons, making the SLS the only heavy-lift vehicle capable of placing it into orbit. That fact was acknowledged by Bigelow Aerospace Vice President Jay Ingham as well. “If a super-heavy-lift launch vehicle ever did exist, probably in the range of around 100 metric tons, would require an 8-meter fairing to launch the BA-2100,” Ingham discussed during the Symposium.

“SLS allows delivery of the BA-2100 via direct insertion to a low earth orbit and is the only launch vehicle capable of delivering a payload this large to LEO,” notes Boeing in its LUS concept presentation. Besides being used as a space hotel complex or space science research laboratory in low-Earth orbit, the BA 2100 could also be used as a large self-sufficient crew habitat for long interplanetary missions to Mars or anywhere else in the Solar System.

The main purpose of the SLS is to enable beyond-Earth orbit human space exploration. In 2011 Boeing proposed a design for a cislunar Exploration Gateway Platform, located in the L1 or L2 Lagrangian points of the Earth-Moon system. This mission concept envisioned the use of existing left-over hardware from the ISS program for the construction of a cislunar manned outpost that would enable regular access to cislunar space and the lunar surface itself. Many within the space agency view this concept as the next logical step beyond low-Earth orbit for human exploration, serving as a testing ground for long-duration missions prior to a human trip to Mars. “Building a translunar outpost is an important first step in retrieving an asteroid, returning to the moon or venturing to Mars.
Using the SLS/LUS would allow the Exploration Platform to be constructed and crewed in only two launches, as opposed to the four missions required using SLS/ICPS (interim Cryogenic Propulsion Stage), thus saving cost and significantly shortening the time required to start accruing the benefits of a crewed Exploration Platform in translunar space,” notes the new Boeing study.

Boeing’s proposal for an Exploration Gateway Platform, at a Lagrangian point in the Earth-Moon system. Image Credit: Boeing/NASA

A mockup of the proposed Bigelow BA 2100 inflatable module. With a projected payload mass between 70 to 100 metric tons, the only launch vehicle existing or under development that could place it to orbit is the SLS. Image Credit: Bigelow Aerospace

Besides human space exploration, the LUS could greatly advance robotic exploration as well, with its ability to directly send large interplanetary spacecraft to their destinations to the outer Solar System, mitigating the need for multiple gravity-assist manuevers that greatly prolong the mission duration to many years or decades.

The Interim Cryogenic Propulsion Stage currently designed for the SLS Block I version uses a 5m payload fairing that is capable of sending approximately 3 metric tons of payload to Jupiter, 1.8 tons to Saturn, and just 0.13 tons to Uranus. The proposed LUS upper stage, featuring an 8.4m payload fairing, would be capable of sending three to four times more massive payloads to these destinations.
Depending on the LUS variant being used (having a single, dual, or 4-engine configuration), the new upper stage could directly send a payload of approximately 8.5 metric tons to Jupiter, 6 tons to Saturn, and 2 tons to Uranus. This payload capability would enable new and exciting missions to Europa, Titan, Enceladus, and Uranus that just aren’t possible with existing launch vehicles today.
“The SLS provides a critical heavy-lift launch capability enabling diverse deep space missions,” states the Boeing report. “The added payload to destination that can be provided by a new Large Upper Stage, would be an enhancement for future science, astronomy, and Human spaceflight missions.”

The 4-engine configuration of Boeing’s proposed Large Upper Stage for the SLS. Image Credit: NASASpaceFlight.com

The new SLS/LUS lift capability would enable a Europa orbiter or lander to reach the Jovian moon in approximately three years after launch, and a similar mission could reach Titan in four. “Imagine the science return with SLS, where we can get there within a few years, and how that can accelerate scientific discovery,” says Crocker. “We don’t know what we’re going to find in science, but we do know that if you find it sooner, you get a much higher science return for your investment.”

A dedicated Uranus orbiter has also been the longing of the planetary science community. A Uranus orbiter is listed as the third highest priority Flagship mission after Mars and Europa in the 2013-2022 U.S. Planetary Science Decadal Survey. Dr. Mark Hofstadter, a planetary scientist at NASA’s Jet Propulsion Laboratory, stressed that point during a presentation at the January 2013 meeting of the Outer Planets Assessment Group, in Atlanta, Ga. “The Group is concerned that no action was taken on its findings last year regarding a Uranus mission study,” notes Hofstadter in the presentation, “and again urges that NASA initiate such a study responsive to Decadal Survey science goals for the ice giants.”

The 8m primary mirror version of the proposed ATLAST space telescope. Image Credit: NASA, MSFC Advanced Concepts Office

Planetary exploration wouldn’t be the only field in space science that could benefit from the use of the SLS/LUS concept. The new upper stage would also be able to lift the proposed Advanced Technology Large Aperture Space Telescope, or ATLAST, that is under consideration by NASA. ATLAST is a next generation space telescope, featuring a monolithic 8m primary mirror, four times bigger than the one on the Hubble Space Telescope. An alternative design also calls for a 16m segmented primary mirror, which could also fit inside the bigger LUS payload fairing. According to the Space Telescope Science Institute’s project website, “ATLAST will have an angular resolution that is 5 – 10 times better than the James Webb Space Telescope and a sensitivity limit that is up to 2000 times better than the Hubble Space Telescope … It is envisioned as a flagship mission of the 2025 – 2035 period, designed to address one of the most compelling questions of our time. Is there life else where in our Galaxy? It will accomplish this by detecting ‘biosignatures’ (such as molecular oxygen, ozone, water, and methane) in the spectra of terrestrial exoplanets.”

Maybe the most important aspect of the LUS design is its cost-saving approach to the SLS’s development. If chosen by NASA, the LUS would be constructed at the agency’s Vertical Weld Center at Michoud Assembly Facility in New Orleans, where Boeing already will be constructing the SLS’s Core Stage, without the need for extra welding or other machining equipment, thus helping to further bring the SLS’s development costs down.
Video Credit: NASA/Marshall Space Flight Center

Since its inception in 2011, the SLS has been heavily criticised by many within the space community for its perceived lack of missions. During her recent appearance on a radio talk show, former NASA Deputy Administrator Lori Garver heavily criticised SLS as being a rocket to nowhere.“Where is it going to go?” she asked during the show. Although Boeing’s LUS upper stage concept hasn’t been yet approved by NASA, it nevertheless largely invalidates Garver’s criticism by showcasing that the space agency’s newest heavy-lift vehicle could be used for all shorts of exciting and ambitious human and robotic missions throughout the Solar System.