The birthday boy had to miss out on his birthday since he was “unwell” and the situation doesn’t look too rosy. He was in the hospital and was discharged last Friday. Sunday was too early for him to get out of bed rest. He has defied death for more than 40 years now, given that at an age of 28 he was told that he wouldn’t live for more than 6 months.
Repeated illnesses like pneumonia have robbed him of his voice. Now he can barely more a muscle of his cheek. This creates pressure differences on a nearby sensor and this lets him choose particular letters, words or phrases on a computerized system to which he is wired. These are then put together and the composition is read out using a computerized voice. However, old age is threatening to seize even this meager resource he has. Deterioration of cheek muscle is making him harder to compose his spoken words. This is the reason why he always asks for questions to be submitted before an event, so that he may compose the answers beforehand. On a certain occasion during his TED Talk, he took 7 minutes to compose a sentence as an answer to a question from the audience, which wasn’t submitted to him beforehand.
Hawking’s 70th birthday will be marked by the opening of a new exhibition of his achievements at the London’s Science Museum on the 20th of January.
The 100-m Green Bank Telescope in Virginia has just picked up a strange radio signal, originating from KOI 817 (with KOI standing for Kepler Object of Interest) that looks as if an alien civilization is transmitting to us. SETI is excited as this is the type of radio signal it would expect from an alien civilization.
Not from an alien world
However, before the excitement can get too wild, SETI says that this signal is definitely terrestrial, rather than extraterrestrial. The signals have “terrestrial radio frequency interference” or RFI. Right now, the signals are a great source for SETI astronomers to study radio-frequencies, should they encounter a radio-emitting alien civilization.
The radio signals are narrow in frequency range (photo above), much narrower than anything that would be produced by an astrophysical radio source. The frequency of the signals is also perfect! Even the Doppler shift is just right, with the frequency decreasing at the precise rate expected from the relative motion of the transmitter and the receiver. A team from UC Berkeley has this to say:
These signals look similar to what we think might be produced from an extraterrestrial technology. They are narrow in frequency, much narrower than would be produced by any known astrophysical phenomena, and they drift in frequency with time, as we would expect because of the Doppler effect imposed by the relative motion of the transmitter and the receiving radio telescope
Kepler has been remarkably successful in detecting exoplanets. It has achieved much success by looking at ‘transits’, or the passage of planets in front of their suns. Kepler needs four transits to confirm the existence of an alien planet. This takes around 3.5 years.
So, tantalizing it might seem, but it’s just not true. Kepler has not yet found alien life, leave alone intelligent alien life. But the search continues…
The man closest to death enjoys life to the hilt! Stephen Hawking, one of the foremost authorities in the world on gravitational physics and a pioneer in the field of black holes, turns 70 tomorrow (8th January)! He is known for thinking deep about the greatest mysteries of the cosmos. And he thinks the most about that great mystery of all mysteries – “Women. They are a complete mystery”, he says.
You’ve probably heard all about his disabilities and his crippling motor neuron disease. I won’t tell you any of that! I’ll rather talk about his life – the one thing that makes him more lively than most of the completely-able.
Hawking and His Science
Hawking has been a pioneer in the study of black holes. No course on black holes, or even on gravitational physics, can conclude without his name being mentioned. He has contributed immensely to the worldwide discussion on the famous Black Hole information paradox and then did remarkable work in interpreting the meaning of Black Hole entropy. How can Black Holes, an inevitable conclusion of Einstein’s General Theory of Relativity, be compatible with the second law of thermodynamics, which says that disorder of the Universe should always increase? What happens to disorder present in a box of hot gas, when you throw it in a black hole? Isn’t the disorder of the Universe decreasing, since you cannot see inside a black hole?
The ingenious and inevitable conclusion of ‘Hawking radiation’, the mechanism due to which black holes can evaporate, bears his name. Even Black Holes die! Hawking’s spirit doesn’t!
Hawking and his Fame
Hawking is not shy of the limelight. His first book – A Brief History of Time – a smash hit best-seller, which set a record for being the No.1 book on the Amazon best-selling list for the longest time, was written when he was in dire financial straits. The book fed on the fascination of the layman for what lies beyond, but who is too ill-equipped to know. It discusses length scales in the Universe, Penrose diagrams and curvatures, all the while speaking to the audience which might not have a major in physics. And, wonder of wonders, it gets the message across. Since then, Hawking has penned many popular books – ‘The Universe in a Nutshell’, ‘On the Shoulders of Giants’, ‘A Briefer History of time’ and ‘The Grand Design’, the last two being co-authored by physicist Leonard Mlodinow. These have propelled Hawking to a stature of the icon of science for the public and an inspiration for the masses.
Hawking is famously naughty. If he doesn’t like anything that was said to him, he often drives his wheelchair over their feet. More than the grimace due to the slight pain, Hawking likes the expression of utter astonishment on the face of the victim. His regret: he has never ridden over the foot of Margaret Thatcher! His bravado, often bordering on madness, especially given his physical condition, is a constant source of joy for him, especially when people scurry around worrying that he might be injured in some way.
And worrisome it was, when Hawking had contracted pneumonia from a visit to CERN in 1985. It was nearly fatal and he had to lose whatever little remained of his voice to tracheotomy. Hawking remained as unfazed as ever!
Hawking and his God
If anything, his voice has gotten louder! His metaphorical use of the word ‘God’ in “A Brief History of Time” had allowed certain religious apologists to claim that even Hawking believes in some sort of divine providence. Hawking has since not only shut them up, but invited their ire. He famously said that “Heaven is a fairy tale” and that the Universe can do without a designer. His ex-wife Jane said that during their divorce proceedings he said that he was an atheist. Hawking never publicly said that, but his stance on religion can be gauged from the statement he made in 2010:
There is a fundamental difference between religion, which is based on authority, and science, which is based on observation and reason. Science will win because it works.
For a man who has been afflicted with too much suffering and yet who describes himself as lucky, since his imposed slow life-style allows him to spend a lot of time pondering over the questions, heaven cannot possibly be an attractive proposition; he is too alive now! Alive enough to ponder of the greatest questions and posit answers to them. Especially the greatest question of all: Women.
Time has finally been punched through, even though for a very short period of time. Scientists, using the technology for making invisibility cloaks’, have bent light in a tight circle, creating a time cloak. The effect lasts for 40 trillionths of a second.
The art of invisibility
This is the basic idea: If you can make sure that light doesn’t scatter off or reflect of a certain object, that object is invisible. Now, assume that an event occurs, but the lights are switched off at that precise point of time. You don’t register that event. What researchers mean to do is to create this gap in the continuum of light, which then becomes akin to making a small hole in time itself.
Cornell physicist and study co-author Alex Gaeta explains better:
Imagine that you could divert light in time slow it down, speed it up so that you create a gap in the light beam in time. In this case, any event that occurs at that instant of time won’t lead to scattering of light. It appears as if the event never occurred.
He goes on splendidly:
If a device would perhaps speed up a portion of the beam and slow down another portion of it so that there is an instant of time with no beam. You could pass through, and then [on the other side of the event] the device would do the oppositeâ€”speed up the part that had been slowed and slow the part that had been sped up. That would put the beam of light back together, so to speak, so that the detector never recognizes that anything has happened.
Bending light in the temporal dimension
Gaeta and colleagues have used a device called a time lens’. It bends light, not in spatial directions, but in temporal direction. It uses the trick described above, only with higher sophistication and precision to create gaps in the continuum.
Tweaking time with light might be more than just a gimmick in terms of technological value. It might be used in cryptography, using the time lens to create gaps in codes, passed through optical fibres and then reverse them using a second laser source. The information can be sent and received perfectly, but during the transit, it will be highly coded.
Making the hole in space and time a bit bigger and more stable is the current focus. Also, the team is looking to make a three dimensional hole in space (along with the one in time) and this will require great synchronization from six different lasers, rather than just the two used for the one-dimensional case.
A manhole like plate with holes punched in a certain distribution may be the key to understanding the greatest problem facing cosmology at the moment. David Schlegel plans to investigate the nature of Dark Energy and its effect on galaxies using aluminium discs, 2,200 in all, all with a specific set of holes punched in through them. These can be used to view a part of the sky using the 2.5-metre telescope at Apache Point Observatory in New Mexico.
Looking at galaxies…
The scientists will then take spectrum from each of the galaxies. This will yield valuable information as to how fast they are moving away from us, giving hints about the effect of dark energy on these celestial congregations. The discs are to be used for looking at a particular section of the sky. Each hole, when looked through, allows the telescope to stare at only one galaxy. This will eventually collect data from as many as 1.5 million galaxies! The project began in 2009 and is all set to present its first set of data on the 11th of January.
David Schlegel, the principal investigator of the project, called Baryon Oscillation Spectroscopic Survey (BOSS), says:
The more galaxies we get, the better.
… And more than looking at galaxies
BOSS is doing more than just looking at galaxies and their recession speeds. Looking at galaxies and their distribution, the team has found signatures of clumping of galaxies. This is in contrary to the near-uniform distribution of galaxies that one might expect to see. This might be a remnant of a disturbance right after the Big Bang, whose signature just failed to wash away! In fact, it is believed that random quantum fluctuations, called Baryon Acoustic Oscillations, disturbed the uniform energy density distribution of the Universe, right after the inflationary phase, and this process seeded regions where matter could clump together. As more matter fell, gravity aided in the cascade-like process. These became galaxies. Whether there are fainter and less familiar structures contributing to the overall structure of the Universe, we just don’t know.
BOSS takes over from the previous WiggleZ survey, which surveyed about 240,000 galaxies, as compared to BOSS’s 1.5 million. The BOSS team is already planning to get BigBOSS. This will be the ultimate megaproject, sampling about 20 million galaxies and peering deep into the Universe and seeing older and older structures!
How wonderful that this should come at a time, when the public perception was freshly filled accelerated expansion of the Universe, given that the Nobel Prize in 2011 was given for findings on the accelerated expansion of the Universe, using Type Ia supernovae. BOSS, and BigBOSS, will definitely do better!
While space is often referred to as “the final frontier”, a grand and mysterious world awaits exploration in our own back yard. Scientists from the University of Oxford,University of Southampton, the National Oceanography Centre, and British Antarctic Survey have explored the nether regions of the Antarctic Ocean. What it revealed to them was a mysterious world teeming with life and may redefine our understanding of the biogeography of hydrothermal vents.
Hydrothermal Vents of East Scotia Ridge
Using a Remotely Operated Vehicle (ROV), scientists were able to explore the hydrothermal vents of the East Scotia Ridge (ESR). The vents were located in the extreme depths of the Antarctic Ocean. A map below shows the ridge location and it’s proximity to the other continents.
This expedition marks the first time that researchers were able to explore the depths of the ESR. Here they found hydrothermal vents called “black smokers”, like the one pictured below, which reach temperatures up to 382 degrees Celsius. The team reported their findings in this week’s PLoS Biology.
Life in the Great Deep
Hydrothermal vents all over the world have proved to be a breeding ground for a variety of new fauna. The ESR site did not disappoint.
The first survey of these particular vents, in the Southern Ocean near Antarctica, has revealed a hot, dark, lost world’ in which whole communities of previously unknown marine organisms thrive’, said Professor Alex Rogers of Oxford University’s Department of Zoology.
Rather than getting their energy from sunlight as most of the world we are familiar with, vent creatures gather energy from breaking down chemicals such as, hydrogen sulphide. The following images highlight some of the wonderful discoveries that were made.
A Whole New World
Just as amazing as finding all of these new creatures, was the lack of other creatures familiar to hydrothermal vents across the globe. It was once thought the Antarctic region might have acted as a gateway connecting the vents of the Pacific and Atlantic oceans. What turned out to be true was that this area is its own biological region. Professor Rogers said, “Many animals such as tubeworms, vent mussels, vent crabs, and vent shrimps, found in hydrothermal vents in the Pacific, Atlantic, and Indian Oceans, simply weren’t there.” Now they believe that vent systems may be more diverse globally and that the Antarctic Ocean may act as a barrier instead of a gateway between global vents.
These findings are yet more evidence of the precious diversity to be found throughout the world’s oceans,’ said Professor Rogers. Everywhere we look, whether it is in the sunlit coral reefs of tropical waters or these Antarctic vents shrouded in eternal darkness, we find unique ecosystems that we need to understand and protect.’
Such research is vital to our understanding of how these creatures are dispersed and prevents we humans from damaging the fragile environments of these creatures out of ignorance. It only goes to show how much there is still left to learn in our own world.
Both have been criticized for the lack of any experimental data. Now, one might be made or broken by a test. We are talking about the two theories of quantum gravity String Theory and Loop Quantum Gravity – and the latter is all set to be tested. A French team intends to test the correctness of Loop Quantum Gravity (LQG) by simulating the expected signatures of the evaporation of a black hole.
The Difficult Job
The main problem in testing these two theories lies in the fact that one has to probe Planck scale physics and the high energy associated with that. However, Monte Carlo simulations show the way out, or so thinks the team of A.Barrau, T. Cailleteau, X.Cao, J.Diaz-Polo and J.Grain, whose paper appeared in Physical Review Letters.
The plan is daunting. They plan to observe black holes evaporating via the Hawking radiation mechanism and this should reveal critical signatures, if LQG is true. Also, bigger black holes and smaller ones give different signatures. The paper presents the simulations that they have done and what signatures in the radiation pattern they expect to see.
The tough job comes after that. LQG predictions indicate features in the black hole evaporation spectrum, but in order to get that one needs to look at a large number of black holes, so that the energy reconstruction can be done with as little error as possible.
Barrau’s team is also looking at signatures of LQG in the cosmic background radiation. But, that’s another story.
China is fast becoming the biggest threat’ to the American supremacy in space. They plan to put their very own astronaut on the Moon. The intention of a manned spacecraft to the Moon comes after the Chinese had revealed extravagant plans to build its own space station. An officially written white paper provides the future goals for the Chinese space program.
China plans to enter the space exploration grand stage in three steps. The first one involves the said lunar mission. The next one involves replicating what NASA has done with the LRO, viz. putting a satellite around the moon. The last one involves returning lunar samples to study back to Earth.
This is probably the worst news for NASA’s space program. It is still to recover from the retirement of the space shuttle fleet and is dependent heavily on the Russians for trips to and from the space station. Also, the weakening economy is not helping things.
The Chinese have a long way to go, though, before they can even begin to think about challenging the US supremacy. No hard deadline has been given, but unofficial word indicates that the Chinese would like to put up the space station by 2020 and the man on the Moon by 2025.
Ken Pounds, a researcher at Leicester University, UK, thinks this might be a blessing in disguise for the faltering US space program:
Assuming the Chinese are serious, which recent history suggests they are, then I believe the impact could be game-changing. “It is very unlikely the U.S. would not respond. That could breathe new life into their space exploration programme, which is currently going nowhere.
Space exploration is a great idea, but history tells us a grim and different story about two powers trying to outdo one another in that regard. Let us just hope that space remains a peaceful frontier for man, for ever!
Cosmic fireworks are all set to light up the night sky in the early hours of 4th Jan, 2012. A little known meteor shower, the Quadrantids, will set the sky ablaze during a brief, but intense meteor shower. Unfortunately, only Northern Hemisphere residents will be able to see the shower. The peak will be at about 3 AM EST in the morning. With the moon setting at about this time, skywatchers will be able to get a great view! The frequency of the showers is expected to cross 100 per hour for a very brief duration.
Where to Look
The Quadrantids are named after an extinct constellation, Quadrans Muralis. It will be hedged in between the Draco constellation to the North, the Big Dipper and the Arcturus constellation further east. It will be close to the Pole Star, so if you can identify that you’ll be home dry! You can alternatively get a compass to point North and that’ll do it too!
The showers will be visible best to the residents in the higher latitudes. North Americans and Canadians will be getting a brilliant view. The Quadrantids have been known to clock counts at even 200 per hour. However, the window of opportunity is really small about a matter of a few hours and only on one day. This is in contrast with the more famous Geminids and the Perseids, which can be seen for days.
The New Year got off to a great start for NASA as it managed to put the twin GRAIL probes in an orbit around the Moon. They are now set to beam each other radio signals, which will keep them synchronized in orbit and the distance from one probe to the other can be known to an error margin or a micron!
Measuring the gravity of the situation
The GRAIL probes are designed to accurately measure the Moon’s gravitational field strength. The technique is pretty simple really! When one of the probes passes close to a lunar region, which has high density, it will feel a greater gravitational pull. This will suddenly accelerate the probe and the distance between the two probes will decrease. This is how the density map of the moon can be prepared. Of course, it’s never as easy as this, is it?
Why map the moon anyway? The gravity map of Earth’s closest satellite can give us a good map of the composition of the moon. One of the mysteries that might be solved is why the two faces of the Moon look so very different; one is rolling flatlands, without any craters, while the other one is puckered with numerous craters.
The GRAIL probes will now descend and sink lower into its orbit, getting closer to the Moon’s surface. The data acquisition is supposed to start early March, when the probe is 34 miles above the lunar surface.
Getting young minds into the project
One of the best things about this mission is the attempt to get students into this thing. As Phil Plait writes in his blog, Bad Astronomy, there will be four cameras on each of the probes, called MoonKAM. These will get high resolution photos of the lunar surface and these can be used by middle school students. They may even request NASA to fly the probes over a particular area on the Moon. As Phil Plait puts it:
That’s very cool! â€¦ I’ll bet it’ll be an experience they’ll remember their whole lives.
I’m sure too! Being part of science is sometimes being like a detective, without the dirty work!