Researchers Brew Up Organics on Ice
|3:02:14 AM, Thursday, September 27, 2012|
"(www.jpl.nasa.gov, September 18, 2012)
Would you like icy organics with that? Maybe not in your coffee, but researchers at NASA's Jet Propulsion Laboratory in Pasadena, Calif., are creating concoctions of organics, or carbon-bearing molecules, on ice in the lab, then zapping them with lasers. Their goal: to better understand how life arose on Earth.
In a new study published in the Astrophysical Journal Letters, the research team provides the first direct look at the organic chemistry that takes place on icy particles in the frigid reaches of our solar system, and in the even chillier places between stars. Scientists think that the basic ingredients of life, including water and organics, began their journey to Earth on these lonesome ice particles. The ice and organics would have found their way into comets and asteroids, which then fell to Earth, delivering "prebiotic" ingredients that could have jump-started life.
The various steps needed to go from icy organics to slime molds are not clear, but the new findings help explain how the process works. The lab experiments show that organic material can begin the processing it needs to become prebiotic -- while still frozen in ice.
"The very basic steps needed for the evolution of life may have started in the coldest regions of our universe," said Murthy Gudipati, lead author of the new study at JPL. "We were surprised to see organic chemistry brewing up on ice, at these very cold temperatures in our lab."
The organics looked at in the study are called polycyclic aromatic hydrocarbons, or PAHs for short. These carbon-rich molecules can be found on Earth as combustion products: for example, in barbecue pits, candle soot and even streaming out of the tail pipe of your car. They have also been spotted throughout space in comets, asteroids and more distant objects. NASA's Spitzer Space Telescope has detected PAHs in the swirling planet-forming disks around stars, in the spaces between stars and in remote galaxies.
Murthy and his colleague Rui Yang of JPL used their lab setup to mimic the environment of icy PAH molecules in the quiet cold of space, at temperatures as low as 5 Kelvin (minus 450 degrees Fahrenheit, or minus 268 degrees Celsius). First, they bombarded the particles with ultraviolet radiation similar to that from stars. Then, to determine the products of the chemical reaction, they used a type of laser system known as MALDI (for Matrix Assisted Laser Desorption and Ionization), which involves zapping the ice with both infrared and ultraviolet lasers.
The results revealed that the PAHs had transformed: they had incorporated hydrogen atoms into their structure and lost their circular, aromatic bonds, becoming more complex organics. According to Gudipati, this is the type of change that would need to occur if the material were to eventually become amino acids and nucleotides -- bits and pieces of protein and DNA, respectively.
"PAHs are strong, stubborn molecules, so we were surprised to see them undergoing these chemical changes at such freezing-cold temperatures," said Gudipati.
Another bonus for the research is that it might explain the mystery of why PAHs have not yet been identified on ice grains in space. While the hardy organics are pervasive in the cosmos as gases and hot dust, researchers have remained puzzled that their signatures do not show up on ice. The new findings show that PAHs, once they stick to the ice surface, are chemically transformed into other complex organics, explaining why they might not be seen.
While the new results teach us that life's journey could have already begun in the very cold regions of the universe, another question remains: Did it arise elsewhere beyond our sun, too? Researchers don't know, but studies like this one help the ongoing search for life beyond Earth."
Endeavour Over The Golden Gate Bridge
|4:36:29 AM, Saturday, September 22, 2012|
-- More images, - flickr
Go here for larger resolution of this one, - 6048 x 4032
-- The space shuttle Endeavour and its 747 carrier aircraft soar over the Golden Gate Bridge during the final portion of its tour of California, Sept. 21, 2012. Photo Credit: (NASA/Carla Thomas)
US Shuttle Endeavour Undertakes Final Flypast
|5:47:49 PM, Friday, September 21, 2012|
"(BBC 21 September 2012) US space shuttle Endeavour is flying by California landmarks in a final air show before it heads for display in Los Angeles.
Piggy-backing on a modified Boeing 747 jet, the 75-ton ship flew past the California state capitol, Golden Gate Bridge and the Hollywood sign.
The shuttle appeared over San Francisco at around 09:30 local time (16:00 GMT) and Los Angeles some two hours later.
It is the youngest shuttle from a fleet that includes Atlantis and Discovery.
Endeavour replaced the shuttle Challenger, which was destroyed in an accident in 1986 that killed seven astronauts.
In service since 1992, it has made 25 trips, logged 123m miles (198m km) in space and circled the globe almost 4,700 times.
The space ship's four-and-a-half hour flyover began at 08:15 local time, when it took off from Edwards Air Force Base in California, according to Nasa.
It began by travelling north to Sacramento, the state capital, and San Francisco.
From there, Endeavour turned south and passed over Nasa's Ames Research Center and the Vandenberg Air Force Base as it flew towards Los Angeles.
After 11:30 local time, Endeavour appeared over the city's landmarks, including Disneyland, the Getty Center, Universal Studios and Malibu Beach.
It was expected to land at Los Angeles International Airport at about 12:45 local time.
"We're so excited to be welcoming Endeavour home in grand style with these flyovers," said Jeffrey Rudolph, president of the California Science Center, where the shuttle will appear on display.
In mid-October, Endeavour will parade through the streets of Los Angeles as it makes its way to the California Science Center.
Los Angeles has ordered 400 trees to be cut down and hundreds of utility poles, street lights and traffic lights are to be temporarily removed to let the space shuttle pass through neighbourhood streets.
There are plans for 1,000 new trees to be planted to replace those felled.
Endeavour will be on display from 30 October.
The shuttle departed from Florida's Kennedy Space Center on Wednesday, stopping in Houston, Texas, home to Mission Control and the astronauts.
Atlantis is to remain on display at the Kennedy Space Center in Florida, while Discovery was moved earlier in the year to a Smithsonian museum near Washington DC.
The shuttle prototype, Enterprise, has been put on display in New York City.
Last year, Nasa retired the three ships in its fleet after finishing the US portion of the $100bn (£61bn) International Space Station, a permanently staffed research facility that is owned by 15 countries and flies about 250 miles (402km) above earth.
The closure of the programme was ordered by the White House, so the space agency could devote more resources to destinations beyond low-earth orbit, such as asteroids and Mars.
Nasa is not expected to launch any crewed missions before 2021."
'Seeds' of massive black holes found at the center of the Milky Way galaxy
|4:35:49 AM, Tuesday, September 18, 2012|
"(Phys.org July 20, 2012) A research team at Keio University, led by Associate Professor Tomoharu Oka, has discovered intermediate-mass black hole (IMBH) candidates at the center of the Milky Way Galaxy. It is about 30,000 light-years from the solar system in the direction of Sagittarius. IMBH candidates are considered to be the "seeds" that form and grow massive black holes.
Using radio telescopes, the research team led by Associate Professor Oka has found four “warm, dense (more than 50 degrees Kelvin, more than 10,000 hydrogen molecules per cubic centimeter)” masses of molecular gas at the center of the Milky Way Galaxy. Three of those masses of molecular gas have been expanding. This research suggests that supernova explosions caused the expansion. It is estimated that the largest explosion that occurred in the masses of molecular gas is equivalent to 200 supernova explosions. On the other hand, the age of the gas masses is approximately 60,000 years old. Therefore, it can be inferred that a huge star cluster is buried in one of the gas masses. The mass of the cluster (more than 100,000 times the mass of the sun) is comparable to the largest star cluster found in the Milky Way Galaxy. It is thought that IMBHs are formed within such huge star clusters. Eventually, IMBHs born near the center of the Milky Way Galaxy form/expand into a supermassive black hole at the nucleus of the galaxy.
Many galaxies contain enormous amounts of molecular gas in small areas near their nuclei. Highly condensed molecular gas is a birthplace of lots of stars. Moreover, it is considered to closely relate to activities of galactic nuclei. Therefore, it is important to investigate the physical state and chemical properties of molecular gas at galaxy centers through observation. To obtain detailed observation data, it is best to survey the center of the Milky Way Galaxy in which our solar system exists.
The research team observed emission lines at wavelengths of 0.87 mm, emitted from carbon monoxide molecules in an area of several degrees that includes the center of the Milky Way Galaxy. The ASTE 10 m telescope in the Atacama Desert (4,800 meters above sea level) of Chile was used for observation. More than 250 hours in total were spent on the prolonged observation from 2005 to 2010.
The research team compared this observation data with data of emission lines at wavelengths of 2.6 mm, emitted from carbon monoxide molecules in the same area, which were obtained using the NRO 45m Telescope (Note: 1). When intensity values of emission lines at different wavelengths, emitted from carbon monoxide molecules, are compared, it is possible to estimate temperature and density of molecular gas. In this way, the research team succeeded in drawing detailed distribution maps of “warm, dense” molecular gas of more than 50 degrees Kelvin and more than 10,000 hydrogen molecules per cubic centimeter at the center of the Milky Way Galaxy for the first time ever.
Oka, the research team leader, said, “The results are astonishing.” The “warm, dense” molecular gas in that area is concentrated in four clumps (Sgr A, L=+1.3°, L=–0.4°, L=–1.2°). Moreover, it turns out that these four gas clumps are all moving at a very fast speed of more than 100 km/s. Sgr A, one of the four gas clumps, contains “Sagittarius A*,” the nucleus of the Milky Way Galaxy. Oka added, “The remaining three gas clumps are objects we discovered for the very first time. It is thought that ‘Sagittarius A*’ is the location of a supermassive black hole that is approximately 4 million times the mass of the sun. It can be inferred that the gas clump ‘Sgr A’ has a disk-shaped structure with radius of 25 light-years and revolves around the supermassive black hole at a very fast speed.”
On the other hand, the team found signs of expansion other than rotation in the remaining three gas clumps. This means that the gas clumps, L=+1.3°, L=–0.4°and L=–1.2°, have structures that were formed by supernova explosions that occurred within the gas clumps. The gas clump “L=+1.3°” has the largest amount of expansion energy. Its expanding energy is equivalent to 200 supernova explosions. The age of the gas masses is estimated as approximately 60,000 years old. Therefore, given that the energy source is the supernova explosions, the supernova explosions have continued to occur every 300 years..."
-- I've been falling behind a lot, so bear with me as some of the posts will be a month or two old. Oh and don't forget to follow the "READ HERE" link for the rest of the articles, or just click on the image. Thank you!
Pictures: “Doomsday” Seed Vault Safeguards Our Food Supply
|3:09:44 AM, Tuesday, September 18, 2012|
"(Nat. Geo. 07/2012) A conservationist cradles two vials of peas destined for deposit in the Svalbard Global Seed Vault. The remarkable facility set on a rugged Arctic island off Norway is the ultimate global safety net for food security. It's able to protect up to 2.25 billion seeds from even "doomsday" scenarios like asteroid impacts and nuclear war.
But crop varieties are already vanishing at an astonishing pace for more mundane reasons, from shifting local weather patterns to disuse by farmers adopting new hybrids. The vault represents a chance to save as many as possible.
"I'd say doomsday is happening everyday for crop varieties," said Cary Fowler, executive director of the Global Crop Diversity Trust, which helps manage the facility. "Lots of people think that this vault is waiting for doomsday before we use it. But it's really a backup plan for seeds and crops. We are losing seed diversity every day and this is the insurance policy for that."
Even a seemingly simple crop, such as wheat, may have 200,000 different varieties. And each variety has a suite of individual traits that determine how it fares in high or low temperatures, during droughts, or against certain diseases or pests.
"Even conservative projections of changing climate now indicate that by mid-century huge areas of some countries, in Africa for example, will be experiencing climates that are unlike any that have existed since the beginning of agriculture in those countries," Fowler explained.
"How will they become adapted to future climates? One way they can is by tapping into this rich storehouse of diversity and breeding new crops with traits that allow them to succeed in those climates. It's essential to future food security," Fowler said."
-- Follow the link to see the rest.
The Warp Drive Could Become Science Fact
|2:39:36 AM, Tuesday, September 18, 2012|
"(Discovery.com 9/17/2012) A warp drive to achieve faster-than-light travel -- a concept popularized in television's Star Trek -- may not be as unrealistic as once thought, scientists say.
A warp drive would manipulate space-time itself to move a starship, taking advantage of a loophole in the laws of physics that prevent anything from moving faster than light. A concept for a real-life warp drive was suggested in 1994 by Mexican physicist Miguel Alcubierre, however subsequent calculations found that such a device would require prohibitive amounts of energy.
Now physicists say that adjustments can be made to the proposed warp drive that would enable it to run on significantly less energy, potentially bringing the idea back from the realm of science fiction into science.
"There is hope," Harold "Sonny" White of NASA's Johnson Space Center said Friday (Sept. 14) at the 100 Year Starship Symposium, a meeting to discuss the challenges of interstellar spaceflight.
An Alcubierre warp drive would involve a football-shape spacecraft attached to a large ring encircling it. This ring, potentially made of exotic matter, would cause space-time to warp around the starship, creating a region of contracted space in front of it and expanded space behind.
Meanwhile, the starship itself would stay inside a bubble of flat space-time that wasn't being warped at all.
"Everything within space is restricted by the speed of light," explained Richard Obousy, president of Icarus Interstellar, a non-profit group of scientists and engineers devoted to pursuing interstellar spaceflight. "But the really cool thing is space-time, the fabric of space, is not limited by the speed of light."
With this concept, the spacecraft would be able to achieve an effective speed of about 10 times the speed of light, all without breaking the cosmic speed limit.
The only problem is, previous studies estimated the warp drive would require a minimum amount of energy about equal to the mass-energy of the planet Jupiter..."
First Editions of Jules Verne Novels
|12:27:39 AM, Sunday, September 16, 2012|
-- These are beautiful! One of my very favorite authors.
How old are the first planets?
|6:21:26 PM, Monday, September 10, 2012|
"(Phys.org August 31, 2012) To build a planet you need lots of rubble and that means lots of heavy elements – stuff more massive than atoms of hydrogen and helium. The elemental composition of the collapsing nebula that gave birth to the Sun and the planets of the Solar System included things like iron, silicon and magnesium that form the bulk of rocky planets, and carbon, oxygen, nitrogen, potassium and other such elements that are essential for life.
However, these materials were present in just trace quantities, amounting to no more than two percent of the entire nebula that was otherwise dominated by hydrogen (74 percent) and helium (24 percent). Yet this gaseous cloud was huge; it is estimated that it harbored enough heavy elements to build at least thirty planets like Earth.
These heavy elements – 'metals' in astronomer-speak – don't just materialize out of nothing. They are the products of fusion power within stars, subsequently spewed out across the cosmos on the blast waves of supernovae, lacing the interstellar medium with the raw ingredients for planets. To build up enough of these materials, many stars must first live and die, each one contributing to the evolving chemistry of the Universe, but how much material is really required to build a planet and how quickly did the Universe accrue a sufficient level to do so?
Heavy Metal Planets
Earth was born out of the debris of a protoplanetary disc around a nascent Sun 4.54 billion years ago – a serious chunk of time in anybody's book. Yet the Universe is 13.7 billion years old – the Solar System has been around for just the last third of cosmic history. Is it possible that rocky planets could have formed around other stars much earlier? Are we the new kids on the block by comparison?..."
New Research Identifies Prime Source of Ocean Methane
|10:40:31 PM, Friday, August 31, 2012|
"(Phys.org August 30, 2012) Up to 4 percent of the methane on Earth comes from the ocean's oxygen-rich waters, but scientists have been unable to identify the source of this potent greenhouse gas. Now researchers report that they have found the culprit: a bit of "weird chemistry" practiced by the most abundant microbes on the planet.
The findings appear in the journal Science.
The researchers who made the discovery did not set out to explain ocean geochemistry. They were searching for new antibiotics. Their research, funded by the National Institutes of Health, explores an unusual class of potential antibiotic agents, called phosphonates, already in use in agriculture and medicine.
Many microbes produce phosphonates to thwart their competitors. Phosphonates mimic molecules the microbes use, but tend to be more resistant to enzymatic breakdown. The secret of their success is the durability of their carbon-phosphorus bond.
"We're looking at all kinds of antibiotics that have this carbon-phosphorus bond," said University of Illinois microbiology and Institute for Genomic Biology (IGB) professor William Metcalf, who led the study with chemistry and IGB professor Wilfred van der Donk. "So we found genes in a microbe that we thought would make an antibiotic. They didn't. They made something different altogether."
The microbe was Nitrosopumilus maritimus, one of the most abundant organisms on the planet and a resident of the oxygen-rich regions of the open ocean. When scanning microbial genomes for promising leads, Benjamin Griffin, a postdoctoral researcher in Metcalf's lab, noticed that N. maritimus had a gene for an enzyme that resembled other enzymes involved in phosphonate biosynthesis. He saw that the microbe also contained genes to make a molecule, called HEP, which is an intermediate in phosphonate biosynthesis.
To determine whether N. maritimus was actually producing a desirable phosphonate antibiotic, chemistry postdoctoral researcher Robert Cicchillo cloned the gene for the mysterious enzyme, expressed it in a bacterium (E. coli), and ramped up production of the enzyme. When the researchers added HEP to the enzyme, the chemical reaction that ensued produced a long sought-after compound, one that could explain the origin of methane in the aerobic ocean..."
Extinct Human Genome Reveals Brown-Eyed Girl
|10:29:56 PM, Friday, August 31, 2012|
"(news.discovery.com Aug 30, 2012) The genome of a recently discovered branch of extinct humans known as the Denisovans that once interbred with us has been sequenced, scientists said today.
Genetic analysis of the fossil revealed it apparently belonged to a little girl with dark skin, brown hair and brown eyes, researchers said. All in all, the scientists discovered about 100,000 recent changes in our genome that occurred after the split from the Denisovans. A number of these changes influence genes linked with brain function and nervous system development, leading to speculation that we may think differently from the Denisovans. Other changes are linked with the skin, eyes and teeth.
"This research will help [in] determining how it was that modern human populations came to expand dramatically in size as well as cultural complexity, while archaic humans eventually dwindled in numbers and became physically extinct," said researcher Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Future research may turn up other groups of extinct humans in Asia "in addition to Neanderthals and Denisovans," Pääbo told LiveScience.
Although our species comprises the only humans left alive, our planet was once home to a variety of other human species. The Neanderthals were apparently our closest relatives, and the last of the other human lineages to vanish.
However, scientists recently revealed another group of extinct humans once lived at the same time as ours. DNA from fossils unearthed in Denisova Cave in southern Siberia in 2008 revealed a lineage unlike us and closely related to Neanderthals. The precise age of the Denisovan material remains uncertain — anywhere from 30,000 to 80,000 years of age.
"The Denisovan genome is particularly close to my heart, because it was the first time that a new group of extinct humans was discovered and defined just from DNA sequence evidence and not from the morphology of bones," Pääbo said..."
It’s Time To Build A Space Elevator, Says LiftPort Group In Successful Kickstarter Campaign
|9:02:37 PM, Thursday, August 30, 2012|
"(singularityhub.com 2012.08.30) Building a tower into the Heavens is a prospect that is likely as old as human civilization itself, and for the last 50 years or so, scientists have proposed that the best way to realize the idea is to construct a space elevator. NASA scientists put together plans for such a tower in 2000, but those efforts have been toppled by funding cuts. Now, a once abandoned group of companies aiming to build the first space elevator has reformed and recommitted to the dream with a campaign on Kickstarter. The LiftPort Group launched the project in mid August with a $8,000 goal and had raised over $40,000 just past the halfway point.
For all the excitement about undertaking such an endeavor, the group’s Kickstarter pitch speculates that a functional Earth Space Elevator is “a long way off. Perhaps 20-25 years. Before that happens there are some vital interim steps.”
One step that is a significant change since LiftPort initially conceived of the project is to build the first space elevator not on Earth, but on the Moon. Citing that “several more breakthroughs” are required to build an elevator for Earth, the group says a Lunar elevator can be built with existing technology in about 8 years and serve as a precursor to building the Earth elevator. To accomplish this, a one-year feasibility study for building the infrastructure needs to be conducted that is estimated to cost $3 million, which is just a fraction of the estimated $800 million to $1.5 billion cost for a completed Lunar elevator with a payload of 40-240 kg, according to a podcast form the spring.
Additionally, a precursor to the Lunar elevator will initially be attempted, called the Tethered Towers. Based on the group’s previous work using a ribbon as a tower, the plan is to design a robot capable of climbing 2 km or higher and building a tethered test platform suspended by high-altitude balloons. The previous LiftPort team accomplished a similar feat in 2006 when they had a robot climb 1.5 km up, but Michael Laine, President of LiftPort, stated in the Kickstarter description that the current team consists of a lot of new blood and needs a reachable milestone to fuse as an organization.
If the first tower is a success, the team will set out to tether a 3-5 km tower, which will present its own challenges because of the colder temperatures encountered at those altitudes..."
Crazy Siberian Bear Hunting Armor From The 1800s
|1:02:14 AM, Wednesday, August 15, 2012|
"(Buzzfeed.com, August 2012) The object is being called a Siberian bear-hunting suit, but I suspect it is more likely to be for bear bating than hunting, since I can’t imagine anyone could run around the woods in it. It consists of leather pants and jacket (and an iron helmet) studded all over with 1-inch iron nails about 3/4 in. apart. The nails are held in place by a second layer of leather lining the whole thing and quilted into place between the nails.
So, I guess one would run at the bear as it was running at you, and SQUISH! Then, I guess, one would keep belly-flopping on the injured bear until it was dead.
That's not very sporting."
World's Most Sensitive Dark Matter Detector Set Up
|12:54:15 AM, Wednesday, August 15, 2012|
"(Phys.org, August 13, 2012) The world's most sensitive dark matter detector settled into a new home Friday in an old U.S. gold mine.
And when it starts collecting data later this year, scientists say it could lead to another breakthrough in studies of the universe, on the scale of the recent celebration over the so-called "God particle."
"Dark matter presents a much bigger problem to detect," said Tom Shutt, a physics professor with Case Western Reserve University who's working on the Large Underground Xenon detector, known as LUX.
"If we find it, it's going to be a much bigger shift in our understanding of physics."
Scientists earlier this month announced a breakthrough in the existence of the Higgs boson, a subatomic particle that scientists believe gives other particles mass. It is sometimes called the "God particle" because its existence is key to understanding the early evolution of the universe..."
Scientists Plot Driving Routes for Mars Rover Curiosity
|12:49:49 AM, Wednesday, August 15, 2012|
"(Phys.org, August 14, 2012) Scientists are evaluating driving routes the rover Curiosity may take on its way to a Martian mountain.
The NASA rover landed in Gale Crater near the Martian equator a week ago after an eight-month space flight. Its ultimate destination is Mount Sharp, which rises from the center of the crater.
Since landing, the car-size rover has been undergoing an extensive check of its systems and instruments. Officials said Tuesday that Curiosity has successfully completed an upgrade to its computers.
Engineers plan to have Curiosity move its wheels and take a short test drive in several days, but it will take a month to complete all checkups before the six-wheel rover can begin real driving.
Scientists estimate it'll take about a year to get to the lower slopes of the mountain."
Mars Rover Makes First Colour Panorama
|2:36:44 AM, Friday, August 10, 2012|
"(BBC, August 9, 2012) Nasa's new Mars rover has returned its first 360-degree colour panorama from the surface of the Red Planet.
The Curiosity robot used its wideangle science camera placed high up on a mast to acquire the frames.
The low-resolution vista shows at centre the big mountain that lies in the middle of Gale Crater, the deep depression in which the rover landed.
Curiosity's ultimate goal is to drive towards this peak - informally known as Mount Sharp - to study its rocks.
"This is a very low-resolution panorama," explained Mike Malin, the principal investigator on the rover's Mastcam cameras.
"The individual frames are only 144 by 144 pixels. There are 130 of them in there. It took us about an hour and six minutes to take the mosaic.
"For the full-resolution panorama, the data volume will be 64 times larger, [and] the resolution will be eight times better. But this was pretty enough and interesting enough that we thought it was worth sharing with you guys," he told BBC News.
The colour is what the camera saw. Apart from the process of blending the individual frames, the only modification made was to brighten the image slightly.
Pictures are deliberately acquired underexposed so as not to saturate any bright regions in the field of view..."
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