Quantumaniac is where it’s at - and by ‘it’ I mean awesome.
Over here I post a ton of physics / math / general interesting science related posts. I try to be as informative as possible, all while posting fascinating things that hopefully enlighten us both a little to the mysteries of our truly wondrous universe(s?). Plus, how would you know if the blog exists or not unless you observe it? Boom, just pulled the Schrödinger’s cat card. Now you have to check it out - trust me, it said so in an equation somewhere.
Catching Elephant is a theme by Andy Taylor
Weird Spiral Features Found on Mars
Strange coiling spiral patterns have been found on Mars surface by a graduate student who was doing what many of us enjoy: looking through the high-resolution images from the HiRISE camera on the Mars Reconnaissance Orbiter. Similar features have been seen on Earth, but this is the first time they have been identified on Mars. However, on Mars, these features, called lava coils, are supersized. “On Mars the largest lava coil is 30 meters across – that’s 100 feet,” said Andrew Ryan from Arizona State University. “That’s bigger than any known lava coils on Earth.”
The lava coils resemble snail or nautilus shells. Ryan has found about 269 of these lava coils just in one region on Mars, Cerberus Palus. 174 of them swirl in a clockwise-in orientation, 43 are counterclockwise, and 52 of the features remain unclassified due to resolution limits.
On Earth, lava coils can be found on the Big Island of Hawaii, mainly on the surface of ropey pahoehoe lava flows. They usually form along slow-moving shear zones in a flow; for example, along the margins of a small channel, and the direction of the flow can be determined from a lava coil.
Math peeps - do you see any relation to a Fibonacci spiral? I’m interested to see how this possible connection might be handled.
Ancient Asteroids vs. Earth
Even though the Late Heavy Bombardment is somewhat of a controversial idea, new research has revealed this period of impacts to the Earth-Moon system may have lasted much longer than originally estimated and well into the time when early life was forming on Earth. Additionally, this “late-late” period of impacts — 3.8 billion to 2.5 billion years ago — was not for the faint of heart. Various blasts may have rivaled those that produced some of the largest craters on the Moon, and could been larger than the dinosaur-killing impact that created the Chicxulub crater 65 million years ago.
“Our work provides a rationale that the last big impacts hit over an extended time,” said William Bottke principal investigator of the impact study team at the NASA Lunar Science Institute’s Center of Lunar Origin and Evolution (CLOE), based at the Southwest Research Institute (SwRI) in Boulder, Colorado.
The evidence for these prodigious impacts comes from bead-like impact ‘spherules’ found in millimeter- to centimeter-thick rock layers on Earth and date from the Archean period of Earth’s history, more recent than the estimated LHB period of 4.3 to 3.8 billion years ago.
“The beds speak to an intense period of bombardment of Earth,” Bottke said. “Their source long has been a mystery.”
The millimeter-scale circles and more irregular gray particles are formerly molten droplets ejected into space when an asteroid hit the early Earth. The image at left is from the Monteville layer in South Africa. Courtesy Bruce Simonson, Oberlin College and Conservatory
The circles seen in the image above are all formerly molten droplets ejected into space when an asteroid struck the Earth about 2.56 billion years ago. The droplets returned to Earth and were concentrated at the base of the Reivilo layer in South Africa.
The spherules still contain substantial extraterrestrial material, such as iridium (176 parts per million), which rules out alternative sources for the spherules, such as volcanoes, according to Bruce Simonson, a geologist from the Oberlin College and Conservatory who has studied these ancient layers for decades.
The timing of these impacts also coincides with a record of large lunar craters being created more recently than 3.8-billion years ago.
At least 12 spherule beds deposited between 3.47 and 1.7 billion years ago have been found in protected areas on Earth, such as in shales deposited on the seafloor below the reach of waves.
From these beds, the team found evidence of approximately 70 impacts on Earth during this time period that were likely larger than the Chicxulub impact.
In their paper, which was published in Nature, the team created a computer model of the ancient main asteroid belt and tracked what would have happened when the orbits of the giant planets changed. They extended the work of the Nice Model, which supports the theory that Jupiter, Saturn, Uranus and Neptune formed in different orbits nearly 4.5 billion years ago and migrated to their current orbits about 4 billion years ago, triggering a solar system-wide bombardment of comets and asteroids called known as the LHB.
SOFIA - The World’s Most Unique Observatory
One of the most remarkable observatories in the world does its work not on a mountaintop, not in space, but 45,000 feet high on a Boeing 747. Nick Howes took a look around this unique airliner as it made its first landing in Europe.
SOFIA (Stratospheric Observatory for Infrared Astronomy) came from an idea first mooted in the mid-1980s. Imagine, said scientists, using a Boeing 747 to carry a large telescope into the stratosphere where absorption of infrared light by atmospheric water molecules is dramatically reduced, even in comparison with the highest ground-based observatories. By 1996 that idea had taken a step closer to reality when the SOFIA project was formally agreed between NASA (who fund 80 percent of the cost of the 330 million dollar mission, an amount comparable to a single modest space mission) and the German Aerospace Centre (DLR, who fund the other 20 percent). Research and development began in earnest using a highly modified Boeing 747SP named the ‘Clipper Lindburgh’ after the famous American pilot, and where the ‘SP’ stands for ‘Special Performance’.
Maiden test flights were flown in 2007, with SOFIA operating out of NASA’s Dryden Flight Research Center at Edwards Airforce Base in the Rogers Dry Lake in California – a nice, dry location that helps with the instrumentation and aircraft operationally.
As we have seen, the rationale for placing a multi-tonne telescope on an aircraft is that by doing so it is possible to escape most of the absorption effects of our atmosphere. Observations in infrared are largely impossible for ground-based instruments at or near sea-level and only partially possibly even on high mountaintops. Water vapour in our troposphere (the lower layer of the atmosphere) absorbs so much of the infrared light that traditionally the only way to beat this was to send up a spacecraft. SOFIA can fill a niche by doing nearly the same job but at far less risk and with a far longer life-span. The aircraft has sophisticated infrared monitoring cameras to check its own output,and water vapour monitoring to measure what little absorption is occurring.
The 2.7-metre mirror (although actually only 2.5-metres is really used in practice,) uses a glass ceramic composite that is highly thermally tolerant, which is vital given the harsh conditions that the aircraft puts the isolated telescope through. If one imagines the difficulty amateur astronomers have some nights with telescope stability in blustery conditions, spare a thought for SOFIA, whose huge f/19.9 Cassegrain reflecting telescope has to deal with an open door to the 800 kilometres per hour (500 miles per hour) winds.
Nominally some operations will occur at 39,000 feet (approximately 11,880 metres) rather than the possible ceiling of 45,000 feet (13,700 metres), because while the higher altitude provides slightly better conditions in terms of lack of absorption (still above 99 percent of the water vapour that causes most of the problems), the extra fuel needed means that observation times are reduced significantly, making the 39,000 feet altitude operationally better in some instances to collect more data. The aircraft uses a cleverly designed air intake system to funnel and channel the airflow and turbulence away from the open telescope window, and speaking to the pilots and scientists, they all agreed that there was no effect caused by any output from the aircraft engines as well.
Gorgeous Video from Jupiter and Saturn
The footage in this video is derived from image sequences from NASA’s Cassini and Voyager missions.
The song is The Cinematic Orchestra - That Home (Instrumental).
(Source: vimeo.com)
Sitting on Top of the World
(Source: twistedsifter.com)
Here’s Your Chance to Use a Space Shuttle as a Ferry
NASA is tentatively targeting Friday, April 27 as the date of the historic ferryflight of Enterprise from the Washington, DC area to the New York City metropolitan area, if the weather cooperates. “Managers shifted the flight from Wednesday to Friday because of a large region of low pressure dominating the East Coast. The weather is predicted to be more favorable Friday,” NASA said in a statement today.
Enterprise is a full scale prototype space shuttle orbiter that carried out critical approach and landing tests in California in the late 1970’s, setting the stage for the first shuttle blast off in 1981.The orbiter is named after the famed “Starship” in the iconic TV series “Star Trek”.
Space Shuttle Enterprise is already piggybacked atop NASA’s modified Boeing 747 Jumbo Jet at Dulles International Airport outside Washington, DC and awaits the GO command to take off for New York City’s John F. Kennedy International Airport. Visitors to Dulles Airport can get an exquisite view of Enterprise strapped aboard the Shuttle Carrier Aircraft (SCA) from the upper levels of the Daily Parking garage. Go see it in these few extra days before it departs forever.
Originally the ferry flight had been scheduled for Monday and then switched to Wednesday, April 25. But a powerful storm swept through the US East Coast over the weekend and continuing poor weather has further disrupted the flight plans.
NASA and the FAA are coordinating the flight which is expected to arrive and conduct a series of breathtaking low flyovers over and near various landmarks and historic sites in the New York City between 930 and 1130 a.m, including the Statue of Liberty and the Intrepid Sea, Air and Space Museum – her permanent final home and resting place. The exact route and timing depend on weather and operational constraints.
When the flyover is complete, the SCA will land at John F. Kennedy International Airport and more than 1500 dignitaries are expected to be on hand to welcome Enterprise to the Big Apple.
In the weeks following the arrival, Enterprise will be “demated” from the top of the 747 using a pair of heavy duty cranes and placed on a barge for a dramatic seagoing voyage and will be moved by tugboat up New York’s Hudson River to the Intrepid museum in June. The shuttle will be lifted and placed on the flight deck of the Intrepid, where it will be on exhibit to the public starting this summer in a temporary climate-controlled pavilion.
The Intrepid museum is constructing a permanent exhibit facility nearby to showcase Enterprise and the museum’s space-related exhibits and education curriculum.
Sombrero Galaxy Discovered to be “Two Galaxies in One”
New observations from NASA’s Spitzer Space Telescope show that the Sombrero galaxy is both rotund and a slender disk like our spiral Milky Way, The galaxy, which is a round elliptical galaxy with a thin disk embedded inside, is one of the first known to exhibit characteristics of the two different types. The findings will lead to a better understanding of galaxy evolution, a topic still poorly understood.
“The Sombrero is more complex than previously thought,” said Dimitri Gadotti of the European Southern Observatory in Chile and lead author of a new paper on the findings appearing in the Monthly Notices of the Royal Astronomical Society. “The only way to understand all we know about this galaxy is to think of it as two galaxies, one inside the other.”
The Sombrero galaxy, also known as NGC 4594, is located 28 million light-years away in the constellation Virgo. From our viewpoint on Earth, we can see the thin edge of its flat disk and a central bulge of stars, making it resemble a wide-brimmed hat. Astronomers do not know whether the Sombrero’s disk is shaped like a ring or a spiral, but agree it belongs to the disk class.
“Spitzer is helping to unravel secrets behind an object that has been imaged thousands of times,”said Sean Carey of NASA’s Spitzer Science Center at the California Institute of Technology in Pasadena. “It is intriguing Spitzer can read the fossil record of events that occurred billions of years ago within this beautiful and archetypal galaxy.”
Spitzer captures a different view of the galaxy than visible-light telescopes. In visible views, the galaxy appears to be immersed in a glowing halo, which scientists had thought was relatively light and small. With Spitzer’s infrared vision, a different view emerges. Spitzer sees old stars through the dust and reveals the halo has the right size and mass to be a giant elliptical galaxy.
While it is tempting to think the giant elliptical swallowed a spiral disk, astronomers say this is highly unlikely because that process would have destroyed the disk structure. Instead, one scenario they propose is that a giant elliptical galaxy was inundated with gas more than nine billion years ago.
Early in the history of our universe, networks of gas clouds were common, and they sometimes fed growing galaxies, causing them to bulk up. The gas would have been pulled into the galaxy by gravity, falling into orbit around the center and spinning out into a flat disk.Stars would have formed from the gas in the disk.
“This poses all sorts of questions,” said Rubén Sánchez-Janssen from the European Southern Observatory, co-author of the study. “How did such a large disk take shape and survive inside such a massive elliptical? How unusual is such a formation process?”
Researchers say the answers could help them piece together how other galaxies evolve. Another galaxy, called Centaurus A, appears also to be an elliptical galaxy with a disk inside it. But its disk does not contain many stars. Astronomers speculate that Centaurus A could be at an earlier stage of evolution than the Sombrero and might eventually look similar.
The findings also answer a mystery about the number of globular clusters in the Sombrero galaxy. Globular clusters are spherical nuggets of old stars. Ellipticals typically have a few thousand, while spirals contain a few hundred. The Sombrero has almost 2,000, a number that makes sense now, but had puzzled astronomers when they thought it was only a disk galaxy.
Closing In On Dark Matter
When physicists and mathematicians want to get an idea into circulation before going through all the hoo-hah of peer-reviewed publication, they often post a paper on the arXiv server, where anyone who is curious can go and read it. Some arXiv papers turn out to be important, but much evaporates on closer inspection. Judging whether a new arXiv paper is one or the other can be extremely difficult. That is certainly the case with physicist Christoph Weniger’s paper, “A Tentative Gamma-Ray Line from Dark Matter Annihilation at the Fermi Large Area Telescope,” posted on April 12, on dark matter.
Dark matter, invisible and undetectable, makes up more than a quarter of the universe and has been an enigma to physicists and astronomers for more than a century. While physicists can’t look at dark matter directly, they can try to tell-tale trails that dark matter was present. Weniger has produced an analysis of data that—if it holds up—is a major step forward in explaining dark matter, and might provide the first unambiguous evidence of what this mysterious and elusive substance is.
Of course, we’ve heard dramatic claims like this before that didn’t pan out—and it’s certainly possible this one won’t either. We won’t know which way it goes until other scientists digest the analysis and weigh in, which could take months. And even so, it may take years before the findings are confirmed. In the meantime, it’s worth having a look at this latest experimental claim, if only to see how an outsider —a theorist unaffiliated with an experimental collaboration— occasionally tries to make a splash in the big collaboration world of physics.
The outsider, of course, is Weniger. A post-doc at the Max-Planck Institute of Physics, he is not a member of the collaboration that works on the Fermi Large Area Telescope (the collaboration goes by the acronym Fermi-LAT). However, Fermi-LAT makes its data publicly available, which allowed Weniger to use it for his investigation. In fact, his analysis goes over ground that researchers collaborating on the Fermi-LAT project have already trod. When they analyzed their data in previous years, the Fermi-LAT researchers found no strong evidence for dark matter. Weniger, however, wasn’t convinced. He and a few colleagues opted to re-crunch the Fermi-LAT data and in March, posted hints of dark matter that they had spotted. Weniger’s April 12 paper goes a step further, suggesting he’s spotted an even stronger signal at a specific energy.
Weniger’s analysis relies on a theory that predicts that when particles of dark matter meet, they will annihilate one another and create photons. In principal, you should be able to spot these photons in the form of high-energy gamma rays. Since the Large Area Telescope was built to study gamma rays, it’s an ideal instrument for this kind of search.
Weniger analyzed 43 months of data, which yielded strong evidence for a gamma ray source in the outskirts of the galaxy—a region called the galactic halo—which is exactly where theorists would predict you could find dark energy annihilations. Specifically, he’s claimed to spot the candidate gamma rays at 130 billion electron volts. For those of you keen on the statistical details, he’s claiming it with as much as 4.6 sigma certainty—which is to say, a high degree of certainty. For context: In current particle physics, evidence for the Higgs boson would be accepted as a discovery at 5 sigma certainty, so 4.6 is pretty good. That said, when he incorporates the necessary statistics for his targeted search and sample size, his results drop to a 3.5 sigma certainty, barely strong enough for publication.
What makes Weniger think that he got it right while the insiders at Fermi-LAT got it wrong? His is the first to include a full 43 months of data. Previous Fermi-LAT collaboration publications, such as results published in 2010, are limited to just 11 months.In addition, to updating the dataset, Weniger has developed his own algorithms for the dark matter search, which he believes do a better job understanding the region of the galaxy where dark matter is alleged to be. This improves his chances of distinguishing the sought out gamma rays from other galactic events.
But before we pop open the champagne, there are several important caveats. As Weniger himself acknowledges, several more years of data will be needed before it’s clear whether what he thinks he’s seen is real. In addition, because Weniger isn’t a member of the team that gathers data at Fermi-LAT, it’s possible he doesn’t entirely understand how the technology involved in detecting and collecting the data may affect the data. This is something that only collaborators are likely to have studied with enough care to correct for in their analysis. The paper could amount to nothing more than another dark matter dead end.
Things might get interesting if the Journal of Cosmology and Astroparticle Physics, to which Weniger is submitting this paper, opts to publish. That stamp of approval would set Weniger’s work above a great many other arXived efforts. Another development to watch for is a response from the folks on the Fermi collaboration. They know this data better than anyone, and if there’s something to be learned from Weniger’s approach, they’ll want to take it seriously. If nothing else, this is one more in a string of recent examples that shows how we are closing in on dark matter. For now, we watch and wait.
(Source: blogs.scientificamerican.com)
The Family that Went to the Moon
Well, the family photo, anyway.
On April 23, 1972, Apollo 16 astronauts Charlie Duke and John Young embarked on the third and final EVA of the mission,exploring the Descartes Highlands via Lunar Roving Vehicle. During the EVA, before setting up a Solar Wind Collector, Duke placed a small family photo he had brought along onto the lunar surface and snapped a few photos of it with his Hasselblad film camera. This is one of the photos.
The portrait shows Charlie, his wife Dorothy, and their two sons Charles and Thomas. It looks like they are sitting on a bench in the summertime.
The family photo, gingerly wrapped in clear plastic and slightly crumpled from being stashed in the pocket of a space suit, was left on the Moon. It presumably still sits there today, use inches away from Charlie’s boot print — which, presumably, is also there. At the time of this writing it’s been exactly 40 years to the day that this photo was taken.
Our Incredible Planet
These incredible images of the planet Earth show it at its most striking and dramatic, and are more akin to those normally taken from Neptune, Mars or Pluto.
The alien-looking images come from a variety of locations across the globe including the White Desert in Egypt, Monument Valley in the U.S., and the Chocolate Hills of Bohol Island in the Philippines. The images include shots of salt plains, rock formations, geysers, sand dunes, mud playas, lava shelves and deserts.
