All posts by Debjyoti Bardhan

Is a science geek, currently pursuing some sort of a degree (called a PhD) in Physics at TIFR, Mumbai. An enthusiastic but useless amateur photographer, his most favourite activity is simply lazing around. He is interested in all things interesting and scientific.

Origin of Man: Recent Studies Challenge The Accepted Evolutionary Tree For Humans

The Human Evolutionary Tree might need revision. Recent studies and analysis of the fossil of a skull discovered in South Africa in 2008 suggest that a new species, Australopithecus sediba, might have been the earliest human ancestor. The skull of the creature shows both human and ape-like characteristics. Homo habilis, the accepted earliest human ancestor, might have to be relegated to the status of a failed species.

The new species on the block

A. sediba dates back to a period two million years ago. This means that it predates Homo habilis by 77,000 years! The skeletons of A.sediba discovered are thought to belong to a female of about 30 years of age and that of a teenage male. They died together, possibly hours apart. The skeleton still shows bits of skin attached to it!

The Skull of Australopithecus sediba

Making Tools and Using them too

What makes A.sediba an exciting prospect is the fact that the species could make and use tools, a fact we can infer from the brain size and the shape of the fingers. X-ray scans of the skull of the young male fossil showed the braincast of the creature. Once the skull cast is known, scientists can work backwards, tracing the marks in the skull and location of the various artery marks to determine the shape and size of the brain. It turns out that the brain was a quarter of the size of the modern human brain, but still bigger than a chimpanzee’s or even Homo habilis‘s. What is more thrilling is the shape of the hands.

The hands of A.sediba had long thumbs, meaning they could do precision work with tools, much like us. This suggests that they could probably make tools and use them! In fact, the grip of A.sediba might have been better than our own, given the fact that the thumb was longer than ours.

The bigger brained and better tool-making A.sediba might really have been our ancestor, rather than Homo habilis. So what of Homo habilis?

What happens to our Evolutionary Tree?


In the accepted view of the evolution of the human species, Homo habilis represents the first creature in the Homo lineage that leads directly to us, Homo sapiens. Homo habilis gave way to Homo erectus, which then split into Homo sapiens and Homo neanderthalensis (Neanderthals). The H.neanderthalensis species went extinct and H.sapiens came to dominate as the only species in the Homo genus. (Look at the graphic below)

The human timeline (Courtesy: National Geographic)

Now, A.sediba challenges that. It aims to replace H.habilis as the first creature that bore human characteristics, rather than ape-like ones. This means that H.habilis is relegated to being a mere species which went extinct, rather being a transitional form for modern humans. It was, by all means, a failed species that just couldn’t survive the evolutionary competition. However, more research and debate needs to be done to establish this hypothesis.The final word has not been said!

One thing is for sure : We are just Children of Africa searching for our own origins, our place in the cosmos and where we came from.

NASA Scrubs GRAIL Launch For A Day: Discover An Awesome Moon Pic While You Wait! [UPDATED]

NASA’s new Moon Mission GRAIL has been scrubbed for another day. The launch is now scheduled for 10th September, weather conditions permitting. While you wait for the launch to happen, you might as well drool over the following photo taken by the Lunar Reconnaissance Orbiter (LRO). The photo has never been seen before and is unique amongst the plethora of moon photos taken over the decades. Here it is!

UPDATE: The Launch was scheduled for the first window. Due to upper atmospheric wind conditions, it has been shifted to the second launch window at 9:08 AM EST (1838 IST and 1408 GMT).  

Launch Webcast Link:

North Pole of the Moon (Courtesy: NASA/ Lunar Reconnaissance Orbiter)

The photo shows Moon’s North Pole. You’ve all heard about the moon’s dark side the side which is permanently hidden from us but this is different. The photo is not actually one photo, but 983 different ones stitched together. The 983 photos were taken over the period of one month! The magical thing about this photo is that the dark regions seen are regions that NEVER receive any sunlight. Remember that the photo was taken over the course of one month, thus the moon was illuminated in every way possible by the Sun. Thus, the dark regions, near the center of the photo really do not receive any sunlight ever!

About the GRAIL launch

Returning to news about the GRAIL launch, the latest from NASA is that the weather on 10th September (i.e. tomorrow) is likely to be 60% co-operative’, which is good enough for a launch. The launch windows remain roughly the same as it was yesterday one at 8:37 AM EST and the next one at 9:12 AM EST. Yesterday’s launch was scrubbed due to high turbulence in the upper atmosphere. While the Delta II rockets would presumably have flown through, NASA did not want to take any chances. It also gives NASA another day to complete another round of checks.

Since, we don’t have launch pictures, we might just as well share a picture of the scrub. The GRAIL spacecrafts, housed safely inside Delta II rockets, sits patiently on the Cape Canaveral Launch Pad.

GRAIL sits silently aboard the Delta II rockets (Courtesy: NASA/JPL-Caltech/Cape Canaveral Air Force Base)

We can afford to take some time it’s not as if someone’s expecting us on the moon.

Resources regarding the launch:  

1. Our Post Giving You all Updated Details:

2. Our Post About the NASA Tweetup Event:

3. NASA’s Webcast Link:

4. NASA’s official GRAIL page:

Discovered: An ‘Invisible’ Alien Planet

The best hidden player in a cosmic game of hide-and-seek has just been given away by its own gravitational attraction. For the first time ever, scientists have identified an invisible alien planet by just noticing the gravitational attraction it exerts on another planet, which has been observed. The game was won by the NASA’s Kepler Space Telescope.

An artist's impression of Kepler 19c tugging stealthily at Kepler 19b, as the latter makes its transit across the host star. (Courtesy: David Augilar, Harvard-Smithsonian Center for Astrophysics)

An Alien World

Kepler detected one alien planet as it made a transit across the star it orbits. However, it was noticed that the transit started five minutes early and ended five minutes later than expected. This could only mean that another planetary body tugs on this planet speeding up or delaying its orbital speed. The observed planet has been named Kepler 19b and the unseen planet, Kepler 19c. This is the first time this technique known as transit timing variation or TTV has been used to figure out the existence of an exoplanet. The planetary system is 650 light years away in the constellation Lyra.

Sarah Ballard of Harvard-Smithsonian Center for Astrophysics explains it in naughty-next-door-kid jargon:

It’s like having someone play a prank on you by ringing your doorbell and running away. You know someone was there, even if you don’t see them when you get outside

What about Kepler 19c?

Almost nothing is known about Kepler 19c, except for the fact that it exists. Generally, all planets fall in two categories rocky planets and gas giants. Kepler 19c can be a rocky planet with an orbital period of about 5-7 days (i.e. it is really close to the host star, but light) or it can be a gas giant with an orbital period of 100 or 200 days (i.e. it is far off, but very massive). Both types would be able to exert similar gravitational influence on Kepler 19b.

Kepler 19c hasn’t been seen transiting the parent star, suggesting that the planes of orbit of Kepler 19b and 19c are oblique to one another. Kepler will keep looking. Kepler has done an excellent job in detecting exoplanets, detecting as many as 1235 planets in its first four months of operation.

The excitement and toil of such a search is the same as that of a murder mystery investigation, but happily without a victim. Did you just say, Elementary…? It is not!

Strong Signals Of Dark Matter Detection Noticed: Huge Announcement Coming In From Germany Conference

Dark matter may finally have been driven out of its hiding place. Scientists report seeing as many as 67 events of dark matter detection at the Cresst Experiment in Italy. This is the startling news coming out of the ongoing 7-day Topics in Astroparticle and Underground Physics Meetingin Germany. The announcement was made yesterday, i.e. on the 6th of September.

Exciting Events

The events have been detected with a four-sigma confidence level, or with about 99.994% confidence. For the status of a discovery, the detection has to be at a five-sigma confidence level or at 99.99994% confidence. Thus, we may say that the signals are extremely strong, but not strong enough to warrant a discovery.

The Cresst Experiment (Courtesy: Max Planck Institute)

What is Dark Matter?

Dark Matter has been predicted to occupy 24% of the Universe, with ordinary matter occupying just 4-5%. The challenge in detecting dark matter is due to the fact that it interacts really weakly with matter (hence, its name). It was introduced into the theoretical framework to explain the rapid spinning of the galactic arms. It soon turned out that fine-tuned Dark Energy Models are needed to explain Cosmic Microwave Background Radiation and Gravitational Lensing.

Dark Matter particles must have mass. Thus, the constituent particles of dark matter are called broadly as Weakly Interacting Massive Particles’ or WIMPs. The Cresst experiment uses supercooled calcium tungstate crystals to search for dark matter particle. When a dark matter particle hits one of the crystals, it scintillates and the detectors can pick up that pulse of radiation and measure the energy of the collision.


While this is great news for most gravitational models, it doesn’t reconcile with the non-detection of dark matter events in the CDMS-II and XENON100 experiments, both of which are also searching for Dark Matter particles. The fact that the detection is not at a 5-sigma confidence level yet means that all hopes of reconciliation are not gone.

Dark Matter may finally have been smoked out of its hiding place, but we’re still not sure of that.

NASA Releases Never Before Seen Photos Of The Moon Showing The Legacy Of The Previous Moon Missions

With no winds or water to wash it off, the Moon has not forgotten its past. Today, September 6th, NASA  released several images of the landing sites of the previous moon missions taken by the Lunar Reconnaissance Orbiter (LRO). These photos are the sharpest ever photos of the lunar surface and the indelible marks left by humans on it.

Image 1: Photo of the Apollo 17 mission landing site. Note the American Flag, hoisted there since the first moon mission. (Courtesy: NASA/JPL-Caltech)

Among the most notable features of the photo are the American flag planted during the historic first moon mission, craters left behind by rockets during launch and footprints of astronauts.

Image 2: Note the ALSEP equipment dump and the Surveyor Crater (Courtesy: NASA/JPL-Caltech)

The LRO also captured the equipment from the ALSEP project, the present location of the Lunar Rover and the Surveyor spacecraft. The ALSEP acronym for Apollo Lunar Surface Experiment Package project comprised of measuring seismological activity on the moon, determining the lunar atmospheric pressure, installing a laser reflector on the surface to return a laser beam so that the earth-moon distance can be accurately measured and gauging the history and effect of meteorite impacts on the lunar surface. ALSEP was a vital ingredient of all the Apollo missions, including Apollo 17.

Image 3: The trail marks were left by astronaut Alan Shepherd. (Courtesy: NASA/JPL-Caltech)

Footprints of the legendary Alan Shepherd, who was the first American to walk in space, can also be found in the photos. He was the fifth man on the moon. He is also known for being the only person to play golf on the moon. The LRO is in its extended mission period and will operate till 2012. Many may view this photo release as a nice PR move just two days before the big GRAIL launch, which will study the gravitational field of the moon in more detail than ever before.

Image and Label Credits: NASA/JPL-Caltech

Innocuous Prehistoric Soil Bacteria Can Destroy Cancer Cells

This is the microbial version of the Good Samaritan story with far greater consequences. A very common soil bacterium Clostridium sporongenes can kill off cancerous cells and can be easily harnessed into a cancer drug. Furthermore, the bacterium does no damage to the cancer patient.

Clostridium sporogenes: Final Answer?

Common Wonder

The bacterium grows only in those places where oxygen is absent, like deep inside the soil or within tumors in the body. It is extremely specific in this aspect and does not grow in places where oxygen concentration exceeds a certain threshold level.

Scientists from Dutch and UK stimulated the production of an enzyme by the bacterium that can serve as a cancer drug. The studies were presented to the Society of Microbiology.

The Procedure

Spores of the bacterium are injected into the patients’ body. Since the microbe grows only in oxygen-depleted regions, it doesn’t grow indiscriminately and latches onto solid tumours. In this anaerobic environment, the bacterium produces a specific enzyme. A separate anti-cancer drug is injected into the patient at the same time, but in an inactive form. When this inactive drug meets the bacteria at the tumour site, the secreted enzyme activates the drug. Once activated, it destroys the cells surrounding it i.e. the tumor cells.

The Ultimate Magic Bullet

The bacterium may really be the magic bullet’ scientists have been searching for. Magic Bullet’ refers to the hypothetical medical concept in which a drug will only act on a specific type of cell or enzyme and not disturb any other component of the body. In case of cancer, the drug must target only cancer cells and not harm the healthy living tissues. C.sporogenes fits the bill perfectly. Since it grows only is low-oxygen regions, it will not grow on healthy tissues, as they are richly supplied by oxygen.

Prof. Nigel Minton explains this bizarre characteristic:

Clostridia are an ancient group of bacteria that evolved on the planet before it had an oxygen-rich atmosphere and so they thrive in low oxygen conditions. When Clostridia spores are injected into a cancer patient, they will only grow in oxygen-depleted environments, i.e. the centre of solid tumors. This is a totally natural phenomenon, which requires no fundamental alterations and is exquisitely specific. We can exploit this specificity to kill tumor cells but leave healthy tissue unscathed

Thus, new age cancer treatments may be non-invasive with little or no side-effects and due to a harmless soil microbe.

The Final Answer may have been under our feet all along. Who’d have thought that the dirt that you wash off your shoes might hold the key to a cancer cure?

Novel Superconducting Material Does The Impossible; May Open Up New Possibilities in Solid State Physics

Whether this has the same effect as Silicon had in revolutionising solid state devices is something that only time will tell, but this certainly seems to have a lot of potential. Researchers at the Stanford Institute for Materials and Energy Sciences (SIMES) have been able to synthesize a new material by sandwiching two nonmagnetic insulators together. The wonderful property is that within this substance, both superconductivity and magnetism exist simultaneously.

A Magical Property

Meissner Effect

Superconductors are substances which allow the flow of current almost unhindered, unlike ordinary conductors, which have resistance. The flow is almost 100% efficient. A peculiar property unique to superconductors is that they expel any magnetic field within them by the so-called Meissner Effect. Ordinary spherical conductors allow a uniform non-zero magnetic field within them. One of the signatures of the onset of superconductivity when such a conductor is cooled is the almost sudden drop of this internal field to zero. So, superconductivity and magnetic field are uncomfortable bedfellows.

New Magical Material

In this novel substance, made by strapping together a thin film of lanthanum aluminate on a strontium titanate substrate, both superconductivity and magnetic field exist together at the boundary. At this junction, current flows with no resistance.

Never has it been seen that superconductivity and magnetic fields help each other. The researchers are still to establish the relation in this system. If they assist one another, it will again pose another interesting problem to the already bulging bag of puzzles in superconductivity. Scientists at MIT confirmed that superconductivity and magnetism indeed exist at the boundary.

Looking for more

The SIMES group is looking at the response of the substance to externally applied electric fields, especially alternating ones. They are also looking at how the substance reacts to being compressed. No one knows why superconductivity and magnetism coexist and that too at the boundary of two nonmagnetic non-metallic substances, but they suspect that some new phenomenon might be afoot contributing to both these effects.

There is, indeed, more magic in physical phenomena than in heaven and earth.

NASA Selects Lucky Few For Tweetup Event For GRAIL’s Thursday Launch

Twitter’s little birdie just got a lift on a NASA rocket bound for the moon. NASA has invited 150 of its Twitter followers to a two-day Tweetup program on the day of the launch and the day before that.

We had told you about the launch here.

The Program

The program will give NASA’s Twitter followers a chance to be the part of the historic launch of the GRAIL spacecrafts on the 8th of September, i.e. upcoming Thursday. The lucky selected few will be expected to do the thing that got them selected in the first place tweet about the program on Twitter.

The Twitter Logo on the Moon. (Courtesy: NASA/JPL-Caltech)

The participants will be meeting important members of the GRAIL mission like NASA administrator Charles Bolden, Maria Zuber, the principal investigator at MIT, Cambridge and astrophysicist Neil deGrasse Tyson. A part of the Tweetup program will be broadcast. The group will also be given a tour of the Kennedy Space Center and Cape Canaveral, which are near the launch site. This part of the Tweetup will begin on Wednesday, 7th September, at 3 PM.

You can watch the broadcast of the tweetup here:

There will also be a mouth-watering visit of the launch-pad from up close.

The 150 participants have been chosen from among 800 participants who registered for the program online. Apart from the U.S., participants hail from India, Brazil, Spain, United Kingdom, Canada, Indonesia and Australia.

For those who were unfortunate enough to miss out, you can still watch the liftoff at NASA’s HDTV initiative program website. For tweets from the Tweetup participants about the program and launch, watch out for the #NASATweetup hashtag on Twitter.

The official site for the GRAIL launch is here:  and

We promise to track any major development and report it here.

Criminal Behavior Might Be Linked To Abnormal Brain Shape; Law Courts Allow Such Evidence

Criminality is an inherent tendency that lies in the brain or at least the law courts think so. A court of law reduced the murder sentence of an Italian woman, Stefania Albertani, since her lawyers proved that her behaviour could be related to the abnormalities in her brain and genes.

Albertani killed her own sister by force feeding her psychotropic drugs and then burning her corpse. She was sentenced to 20 years in prison.


Does this really reveal hidden criminal instinct?

Brain scans are being increasingly used in courts all over the world and quite a lot throughout the US. In fact, in the US, it has become a feature in a number of states and lawyers use suspicious brain scans in the defense of their clients.

The wider question remains does an abnormal shape of the brain really affect the actions of a person? Is there enough correlation to pronounce someone guilty or innocent?


It seems natural enough. A man was booked for paedophilic offences and was later diagnosed with a tumour in his brain. When he was operated on, his paedophilic traits went away. After a few months, when his paedophilic tendencies returned, doctors examined him and found that his tumour had relapsed.

But one case doesn’t solve the issue. Science needs hard statistical correlation before it can deliver a verdict, but apparently no such restriction binds law courts.

Medieval ages experienced such methods of rooting out’ criminals before they had a chance to commit crime by measuring the size of skulls and certain other factors. These methods were utter failures, so now neuroscientists are hoping that something more insightful by looking inside skulls and not just measuring them from outside.

So even though MRI scans might acquit criminals in law courts, science still has a long way to go!

First Quantum Implementation of Von Neumann Architecture Achieved, Large Quantum Computers Next Stop!

The first quantum version of the Von Neumann architecture has been implemented by physicists at University of California, Santa Barbara (UCSB). This represents a crucial step in the creation of quantum computers which will make calculations at least a million times faster. The micro quantum computers are already here!

The implementation of the von Neumann machine on the quantum scale. Courtesy: UCSB

Why such a big deal?

Kindly realise the magnitude of the achievement. The Von Neumann architecture, partly developed and articulated by mathematical genius John von Neumann, is the principal methodology used in building the hardware and supporting software in computers. The architecture came into existence in the 1940’s due to the work of Von Neumann and Alan Turing. Since then, it has formed the bedrock of computer hardware design, even though there have been many improvements on it. However, the architecture has been realised only with classical computers, or computers whose bits are macroscopic physical objects. It has been a major challenge for computer scientists to either build up the quantum analogue of the Von Neumann architecture or to implement using quantum systems.

What is the Von Neumann Architecture?

Here’s what the Von Neumann architecture is. Every Von Neumann machine is made up of four units the Arithmetic-Logic Unit, the Memory, the Control Unit and the Interface. The architecture prescribes that instructions be also stored in the memory, rather than just data. In fact Von Neumann prescribes that the instruction code be stored exactly like data. In response to the code, the data changes and produces intermediate computation results, finally ending up with the end result. The key feature is that the instructions themselves be pliable. They should change with the data i.e. they are self-modifying. They can be encoded in numeric form, just like data, so that this can be achieved. These instructions are then pulled’ up from the memory. Two types of buses’ or data trains link the various components of the Von Neumann machine the data bus and the address bus. The rate at which these buses can transfer data puts a theoretical upper cut-off. This is the von Neumann’ bottleneck.

Realise that the Von Neumann architecture is contradictory to the structure of modern high level languages, where you have definite separation of the data and the instruction code.

Quantum Implementation: Using Qubits

The circuits developed by the UCSB physicists use superconducting quantum circuits, which require extremely low temperatures to operate. The demonstration of the fact that this can be done implies that quantum computing can indeed be achieved on a macroscopic scale. Dreams of Large Scale Integration (LSI) or Very Large Scale Integration (VLSI), achieved long ago with conventional computer components, are not very far-fetched either!

VLSI on the quantum scale?

The key to the quantum implementation of the Von Neumann architecture is quantum bits or qubits. Unlike the classical bit, which can be in either 1 or 0 state, qubits can exist in a superposition of many quantum states, allowing for many more calculations to be done on a single qubit simultaneously. The fundamental unit of a quantum computer comprises two qubits, a quantum communication bus, two bits of quantum memory and a resetting counter. This uses Von Neumann architecture on the nano scale!

The aim of simultaneously writing information to the quantum memory and performing quantum calculations on the qubit has not been achieved, but scientists are close to that. The three-qubit Toffoli gate has already been implemented.

Super-fast calculations, here we come!