News From Space: Cosmic Inflation and Dark Matter

big bang_blackholeHello again! In another attempt to cover events that built up while I was away, here are some stories that took place back in March and early April of this year, and which may prove to be some of the greatest scientific finds of the year. In fact, they may prove to be some of the greatest scientific finds in recent history, as they may help to answer the most fundamental questions of all – namely, what is the universe made of, and how did it come to exist?

First up, in a development that can only be described as cosmic in nature (pun intended), back in March, astrophysicists at the Harvard-Smithsonian Center announced the first-ever observation of gravitational waves. This discovery, which is the first direct evidence of the Big Bang, is comparable to significance to CERN’s confirmation of the Higgs boson in 2012. And there is already talk about a Nobel Prize for the Harvard crew because of their discovery.

big_bangThis theory, which states that the entire universe sprung into existence from a tiny spot in the universe some 13.8 billion years ago, has remained the scientific consensus for almost a century. But until now, scientists have had little beyond theory and observations to back it up. As the name would suggest, gravitational waves are basically ripples in spacetime that have been propagating outward from the center of the universe ever since the Big Bang took place.

Originally predicted as part of Einstein’s General Theory of Relativity in 1916, these waves are believed to have existed since a trillionth of a trillionth of a trillionth of a second after the Big Bang took place, and have been propagating outward for roughly 14 billion years. The theory also predicts that, if we can detect some gravitational waves, it’s proof of the initial expansion during the Big Bang and the continued inflation that has been taking place ever since.

bicep2-640x425Between 2010 and 2012, the BICEP2 – a radio telescope situated at the Amundsen–Scott South Pole Station (pictured above) – the research team listened to the Cosmic Microwave Background (CMB). They were looking for hints of B-mode polarization, a twist in the CMB that could only have been caused by the ripples of gravitational waves. Following a lot of data analysis, the leaders announced that they found that B-mode polarization.

The work will now be scrutinized by the rest of the scientific community, of course, but the general consensus seems confident that it will stand up. In terms of scientific significance, the confirmation of gravitational waves would be the first direct evidence that the universe started out as nothing, erupted into existence 13.8 billion years ago, and has continued to expand ever since. This would confirm that cosmic inflation really exists and that the entire structure of the universe was decided in the beginning by the tiniest flux of gravitational waves.

planck-attnotated-580x372And that’s not only discovery of cosmic significance that was made in recent months. In this case, the news comes from NASA’s Fermi Gamma-ray Space Telescope, which has been analyzing high-energy gamma rays emanating from the galaxy’s center since 2008. After pouring over the results, an independent group of scientists claimed that they had found an unexplained source of emissions that they say is “consistent with some forms of dark matter.”

These scientists found that by removing all known sources of gamma rays, they were left with gamma-ray emissions that so far they cannot explain. And while they were cautious that more observations will be needed to characterize these emissions, this is the first time that potential evidence has been found that may confirm that this mysterious, invisible mass that accounts for roughly 26.8% of the universe actually exists.

darkmatter1To be fair, scientists aren’t even sure what dark matter is made of. In fact, it’s very existence is inferred from gravitational effects on visible matter and gravitational lensing of background radiation. Originally, it was hypothesized to account for the discrepancies that were observed between the calculations of the mass of galaxies, clusters and entire universe made through dynamical and general relativistic means, and  the mass of the visible “luminous” matter.

The most widely accepted explanation for these phenomena is that dark matter exists and that it is most probably composed of Weakly Interacting Massive Particles (WIMPs) that interact only through gravity and the weak force. If this is true, then dark matter could produce gamma rays in ranges that Fermi could detect. Also, the location of the radiation at the galaxy’s center is an interesting spot, since scientists believe that’s where dark matter would lurk since the insofar invisible substance would be the base of normal structures like galaxies.

fermi_gamma-raysThe galactic center teems with gamma-ray sources, from interacting binary systems and isolated pulsars to supernova remnants and particles colliding with interstellar gas. It’s also where astronomers expect to find the galaxy’s highest density of dark matter, which only affects normal matter and radiation through its gravity. Large amounts of dark matter attract normal matter, forming a foundation upon which visible structures, like galaxies, are built.

Dan Hooper, an astrophysicist at Fermilab and lead author of the study, had this to say on the subject:

The new maps allow us to analyze the excess and test whether more conventional explanations, such as the presence of undiscovered pulsars or cosmic-ray collisions on gas clouds, can account for it. The signal we find cannot be explained by currently proposed alternatives and is in close agreement with the predictions of very simple dark matter models.

Hooper and his colleagues suggest that if WIMPs were destroying each other, this would be “a remarkable fit” for a dark matter signal. They again caution, though, that there could be other explanations for the phenomenon. Writing in a paper submitted to the journal Physical Review D, the researchers say that these features are difficult to reconcile with other explanations proposed so far, although they note that plausible alternatives not requiring dark matter may yet materialize.

CERN_LHCAnd while a great deal more work is required before Dark Matter can be safely said to exist, much of that work can be done right here on Earth using CERN’s own equipment. Tracy Slatyer, a theoretical physicist at the Massachusetts Institute of Technology and co-author of the report, explains:

Dark matter in this mass range can be probed by direct detection and by the Large Hadron Collider (LHC), so if this is dark matter, we’re already learning about its interactions from the lack of detection so far.This is a very exciting signal, and while the case is not yet closed, in the future we might well look back and say this was where we saw dark matter annihilation for the first time.

Still, they caution that it will take multiple sightings – in other astronomical objects, the LHC, or direct-detection experiments being conducted around the world – to validate their dark matter interpretation. Even so, this is the first time that scientists have had anything, even tentative, to base the existence of Dark Matter’s on. Much like until very recently with the Big Bang Theory, it has remained a process of elimination – getting rid of explanations that do not work rather than proving one that does.

So for those hoping that 2014 will be the year that the existence of Dark Matter is finally proven – similar to how 2012 was the year the Higgs Boson was discovered or 2013 was the year the Amplituhedron was found – there are plenty of reasons to hope. And in the meantime, check out this video of a gamma-ray map of the galactic center, courtesy of NASA’s Goddard Space Center.


Sources:
extremetech.com, IO9.com, nasa.gov, cfa.harvard.edu, news.nationalgeographic.com

Looking for Dark Matter: The DarkSide-50 Project

darkmatter1If 2013 will go down in history as the year the Higgs Boson was discovered, then 2014 may very well be known as the year dark matter was first detected. Much like the Higgs Boson, our understanding of the universe rests upon the definitive existence of this mysterious entity, which alongside “dark energy” is believed to make up the vast majority of the cosmos.

Before 2014 rolled around, the Large Underground Xenon experiment (LUX) – located near the town of Lead in South Dakota – was seen as the best candidate for finding it. However, since that time, attention has also been directed towards the DarkSide-50 Experiment located deep underground in the Gran Sasso mountain, the highest peak in the Appennines chain in central Italy.

darkside-50This project is an international collaboration between Italian, French, Polish, Ukrainian, Russian, and Chinese institutions, as well as 17 American universities, which aims to pin down dark matter particles. The project team spent last summer assembling their detector, a grocery bag-sized device that contains liquid argon, cooled to a temperature of -186° C (-302.8° F), where it is in a liquid state.

According to the researchers, the active, Teflon-coated part of the detector holds 50 kg (110 lb) of argon, which provides the 50 in the experiment’s name. Rows of photodetectors line the top and bottom of the device, while copper coils collect the stripped electrons to help determine the location of collisions between dark matter and visible matter.

darkside-50-0The research team, as well as many other scientists, believe that a particle known as a WIMP (weakly interacting massive particle) is the prime candidate for dark matter. WIMP particles have little interaction with their surroundings, so the researchers are hoping to catch one of these particles in the act of drifting aloof. They also believe that these particles can be detected when one of them collides with the nucleus of an atom, such as argon.

By cramming the chamber of their detector with argon atoms, the team increases their chance of seeing a collision. The recoil from these collisions can be seen in a short-lived trail of light, which can then be detected using the chamber’s photodetectors. To ensure that background events are not interfering, the facility is located deep underground to minimize background radiation.

darkmatterTo aid in filtering out background events even further, the detector sits within a steel sphere that is suspended on stilts and filled with 26,500 liters (7000 gallons) of a fluid called scintillator. This sphere in turn sits inside a three-story-high cylindrical tank filled with 946,350 liters (250,000) of ultrapure water. These different chambers help the researchers differentiate WIMP particles from neutrons and cosmic-ray muons.

Since autumn of 2013, the DarkSide-50 project has been active and busy collecting data. And it is one of about three dozen detectors in the world that is currently on the hunt for dark matter, which leads many physicists to believe that elusive dark matter particles will be discovered in the next decade. When that happens, scientists will finally be able to account for 31.7% of the universe’s mass, as opposed to the paltry 4.9% that is visible to us now.

planck-attnotated-580x372Now if we could only account for all the “dark energy” out there – which is believed to make up the other 68.3% of the universe’s mass – then we’d really be in business! And while we’re waiting, feel free to check out this documentary video about the DarkSide-50 Experiment and the hunt for dark matter, courtesy of Princeton University:

Sources: gizmag.com, princeton.edu

Looking Forward: Science Stories to Watch for in 2014

BrightFutureThe year of 2013 was a rather big one in terms of technological developments, be they in the field of biomedicine, space exploration, computing, particle physics, or robotics technology. Now that the New Year is in full swing, there are plenty of predictions as to what the next twelve months will bring. As they say, nothing ever occurs in a vacuum, and each new step in the long chain known as “progress” is built upon those that came before.

And with so many innovations and breakthroughs behind us, it will be exciting to see what lies ahead of us for the year of 2014. The following is a list containing many such predictions, listed in alphabetical order:

Beginning of Human Trials for Cancer Drug:
A big story that went largely unreported in 2013 came out of the Stanford School of Medicine, where researchers announced a promising strategy in developing a vaccine to combat cancer. Such a goal has been dreamed about for years, using the immune system’s killer T-cells to attack cancerous cells. The only roadblock to this strategy has been that cancer cells use a molecule known as CD47 to send a signal that fools T-cells, making them think that the cancer cells are benign.

pink-ribbonHowever, researchers at Stanford have demonstrated that the introduction of an “Anti-CD47 antibody” can intercept this signal, allowing T-cells and macrophages to identify and kill cancer cells. Stanford researchers plan to start human trials of this potential new cancer therapy in 2014, with the hope that it would be commercially available in a few years time. A great hope with this new macrophage therapy is that it will, in a sense, create a personalized vaccination against a patient’s particular form of cancer.

Combined with HIV vaccinations that have been shown not only to block the acquisition of the virus, but even kill it, 2014 may prove to be the year that the ongoing war against two of the deadliest diseases in the world finally began to be won.

Close Call for Mars:
A comet discovery back in 2013 created a brief stir when researchers noted that the comet in question – C/2013 A1 Siding Springs – would make a very close passage of the planet Mars on October 19th, 2014. Some even suspected it might impact the surface, creating all kinds of havoc for the world’s small fleet or orbiting satellites and ground-based rovers.

Mars_A1_Latest_2014Though refinements from subsequent observations have effectively ruled that out, the comet will still pass by Mars at a close 41,300 kilometers, just outside the orbit of its outer moon of Deimos. Ground-based observers will get to watch the magnitude comet close in on Mars through October, as will the orbiters and rovers on and above the Martian surface.

Deployment of the First Solid-State Laser:
The US Navy has been working diligently to create the next-generation of weapons and deploy them to the front lines. In addition to sub-hunting robots and autonomous aerial drones, they have also been working towards the creation of some serious ship-based firepower. This has included electrically-powered artillery guns (aka. rail guns); and just as impressively, laser guns!

Navy_LAWS_laser_demonstrator_610x406Sometime in 2014, the US Navy expects to see the USS Ponce, with its single solid-state laser weapon, to be deployed to the Persian Gulf as part of an “at-sea demonstration”. Although they have been tight-lipped on the capabilities of this particular directed-energy weapon,they have indicated that its intended purpose is as a countermeasure against threats – including aerial drones and fast-moving small boats.

Discovery of Dark Matter:
For years, scientists have suspected that they are closing in on the discovery of Dark Matter. Since it was proposed in the 1930s, finding this strange mass – that makes up the bulk of the universe alongside “Dark Energy” – has been a top priority for astrophysicists. And 2014 may just be the year that the Large Underground Xenon experiment (LUX), located near the town of Lead in South Dakota, finally detects it.

LUXLocated deep underground to prevent interference from cosmic rays, the LUX experiment monitors Weakly Interacting Massive Particles (WIMPs) as they interact with 370 kilograms of super-cooled liquid Xenon. LUX is due to start another 300 day test run in 2014, and the experiment will add another piece to the puzzle posed by dark matter to modern cosmology. If all goes well, conclusive proof as to the existence of this invisible, mysterious mass may finally be found!

ESA’s Rosetta Makes First Comet Landing:
This year, after over a decade of planning, the European Space Agency’s Rosetta robotic spacecraft will rendezvous with Comet 67P/Churyumov-Gerasimenko. This will begin on January 20th, when the ESA will hail the R0setta and “awaken” its systems from their slumber. By August, the two will meet, in what promises to be the cosmic encounter of the year. After examining the comet in detail, Rosetta will then dispatch its Philae lander, equipped complete with harpoons and ice screws to make the first ever landing on a comet.

Rosetta_and_Philae_at_comet_node_full_imageFirst Flight of Falcon Heavy:
2014 will be a busy year for SpaceX, and is expected to be conducting more satellite deployments for customers and resupply missions to the International Space Station in the coming year. They’ll also be moving ahead with tests of their crew-rated version of the Dragon capsule in 2014. But one of the most interesting missions to watch for is the demo flight of the Falcon 9 Heavy, which is slated to launch out of Vandenberg Air Force Base by the end of 2014.

This historic flight will mark the beginning in a new era of commercial space exploration and private space travel. It will also see Elon Musk’s (founder and CEO of Space X, Tesla Motors and PayPal) dream of affordable space missions coming one step closer to fruition. As for what this will make possible, well… the list is endless.

spaceX-falcon9Everything from Space Elevators and O’Neil space habitats to asteroid mining, missions to the Moon, Mars and beyond. And 2014 may prove to be the year that it all begins in earnest!

First Flight of the Orion:
In September of this coming year, NASA is planning on making the first launch of its new Orion Multi-Purpose Crew Vehicle. This will be a momentous event since it constitutes the first step in replacing NASA’s capability to launch crews into space. Ever since the cancellation of their Space Shuttle Program in 2011, NASA has been dependent on other space agencies (most notably the Russian Federal Space Agency) to launch its personnel, satellites and supplies into space.

orion_arrays1The test flight, which will be known as Exploration Flight Test 1 (EFT-1), will be a  short uncrewed flight that tests the capsule during reentry after two orbits. In the long run, this test will determine if the first lunar orbital mission using an Orion MPCV can occur by the end of the decade. For as we all know, NASA has some BIG PLANS for the Moon, most of which revolve around creating a settlement there.

Gaia Begins Mapping the Milky Way:
Launched on from the Kourou Space Center in French Guiana on December 19thof last year, the European Space Agency’s Gaia space observatory will begin its historic astrometry mission this year. Relying on an advanced array of instruments to conduct spectrophotometric measurements, Gaia will provide detailed physical properties of each star observed, characterising their luminosity, effective temperature, gravity and elemental composition.

Gaia_galaxyThis will effectively create the most accurate map yet constructed of our Milky Way Galaxy, but it is also anticipated that many exciting new discoveries will occur due to spin-offs from this mission. This will include the discovery of new exoplanets, asteroids, comets and much more. Soon, the mysteries of deep space won’t seem so mysterious any more. But don’t expect it to get any less tantalizing!

International Climate Summit in New York:
While it still remains a hotly contested partisan issue, the scientific consensus is clear: Climate Change is real and is getting worse. In addition to environmental organizations and agencies, non-partisan entities, from insurance companies to the U.S. Navy, are busy preparing for rising sea levels and other changes. In September 2014, the United Nations will hold another a Climate Summit to discuss what can be one.

United-Nations_HQThis time around, the delegates from hundreds of nations will converge on the UN Headquarters in New York City. This comes one year before the UN is looking to conclude its Framework Convention on Climate Change, and the New York summit will likely herald more calls to action. Though it’ll be worth watching and generate plenty of news stories, expect many of the biggest climate offenders worldwide to ignore calls for action.

MAVEN and MOM reach Mars:
2014 will be a red-letter year for those studying the Red Planet, mainly because it will be during this year that two operations are slated to begin. These included the Indian Space Agency’s Mars Orbiter Mission (MOM, aka. Mangalyaan-1) and NASA’ Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, which are due to arrive just two days apart – on September 24th and 22nd respectively.

mars_lifeBoth orbiters will be tasked with studying Mars’ atmosphere and determining what atmospheric conditions looked like billions of years ago, and what happened to turn the atmosphere into the thin, depleted layer it is today. Combined with the Curiosity and Opportunity rovers, ESA’s Mars Express,  NASA’s Odyssey spacecraft and the Mars Reconnaissance Orbiter, they will help to unlock the secrets of the Red Planet.

Unmanned Aircraft Testing:
A lot of the action for the year ahead is in the area of unmanned aircraft, building on the accomplishments in recent years on the drone front. For instance, the US Navy is expected to continue running trials with the X-47B, the unmanned technology demonstrator aircraft that is expected to become the template for autonomous aerial vehicles down the road.

X-47BThroughout 2013, the Navy conducted several tests with the X-47B, as part of its ongoing UCLASS (Unmanned Carrier Launched Airborne Surveillance and Strike) aircraft program. Specifically, they demonstrated that the X-47B was capable of making carrier-based take offs and landings. By mid 2014, it is expected that they will have made more key advances, even though the program is likely to take another decade before it is fully realizable.

Virgin Galactic Takes Off:
And last, but not least, 2014 is the year that space tourism is expected to take off (no pun intended!). After many years of research, development and testing, Virgin Galactic’s SpaceShipTwo may finally make its inaugural flights, flying out of the Mohave Spaceport and bringing tourists on an exciting (and expensive) ride into the upper atmosphere.

spaceshiptwo-2nd-flight-2In late 2013, SpaceShipTwo and passed a key milestone test flight when its powered rocket engine was test fired for an extended period of time and it achieved speeds and altitudes in excess of anything it had achieved before. Having conducted several successful glide and feathered-wing test flights already, Virgin Galactic is confident that the craft has what it takes to ferry passengers into low-orbit and bring them home safely.

On its inaugural flights, SpaceShipTwo will carry two pilots and six passengers, with seats going for $250,000 a pop. If all goes well, 2014 will be remembered as the year that low-orbit space tourism officially began!

Yes, 2014 promises to be an exciting year. And I look forward to chronicling and documenting it as much as possible from this humble little blog. I hope you will all join me on the journey!

Sources: Universetoday, (2), med.standford.edu, news.cnet, listosaur, sci.esa.int

Creating Dark Matter: The DarkLight Project

https://i2.wp.com/scienceblogs.com/startswithabang/files/2011/08/dark_matter_millenium_simulation.jpegFor several decades now, the widely accepted theory is that almost 27% of the universe is fashioned out of an invisible, mysterious mass known as “dark matter”. Originally theorized by Fritz Zwicky in 1933, the concept was meant to account for the “missing mass” apparent in galaxies in clusters. Since that time, many observations have suggested its existence, but definitive proof has remained elusive.

Despite our best efforts, no one has ever observed dark matter directly (nor dark energy, which is theorized to make up the remaining 68% of the universe). It’s acceptance as a theory has been mainly due to the fact that it makes the most sense, beating out theories like Modified Newtonian Dynamics (MOND), which seek to redefine the laws of gravity as to why the universe behaves the way it does.

https://i1.wp.com/www.extremetech.com/wp-content/uploads/2013/04/cdms.jpgLuckily, MIT recently green-lighted the DarkLight project – a program aimed at creating tiny tiny amounts of dark matter using a particle accelerator. In addition to proving that dark matter exists, the project team has a more ambitious goal of figuring out dark matter behaves – i.e. how it exerts gravitational attraction on the ordinary matter that makes up the visible universe.

The leading theory for dark matter used to be known as WIMPs (weakly interacting massive particles). This theory stated that dark matter only interacted with normal matter via gravity and the weak nuclear force, making them very hard to detect. However, a recent research initiative challenged this view and postulates that dark matter may actually consist of massive photons that couple to electrons and positrons.

https://i0.wp.com/www.extremetech.com/wp-content/uploads/2013/10/prototype-a-prime-dark-matter-detector.jpgTo do this, DarkLight will use the particle accelerator at the JeffersonJefferson Lab’s Labs Free-Electron Laser Free Electron Lase in Virginia to bombard an oxygen target with a stream of electrons with one megawatt of power. This will be able to test for these massive photons and, it is hoped, create this theorized form of dark matter particles. The dark matter, if it’s created, will then immediately decay into two other particles that can be (relatively) easily detected.

At this point, MIT estimates that it will take a couple of years to build and test the DarkLight experiment, followed by another two years of smashing electrons into the target and gathering data. By then, it should be clear whether dark matter consists of A prime particles, or whether scientists and astronomers have barking up the wrong tree these many years.

https://i2.wp.com/scienceblogs.com/startswithabang/files/2012/12/sim3dnew.pngBut if we can pinpoint the basis of dark matter, it would be a monumental finding that would greatly our enhance our understanding of the universe, and dwarf even the discovery of the Higgs Boson. After that, the only remaining challenge will be to find a way to observe and understand the other 68% of the universe!

Source: extremetech.com