Now test the purity of milk you consume, on the spot…

Milk is considered to be one of the best sources of nutrients like protein, fat, carbohydrates and minerals making it an ideal food for infants and adults alike. The importance of milk to our dietary needs has made it a prime target for adulteration, the most common method known to us all being the addition of water. Unfortunately, it does not stop there. Harmful chemicals including melamine, formalin, detergents, sugars, urea and a host of other substances are used as adulterants. One common adulteration method used in India is to mix an emulsifier to vegetable oil resulting in a white paste. The paste is then diluted and mixed with chemicals like urea until the consistency of milk is achieved. The proportion of these ingredients is calculated to mimic the fat and solid not fat (SNF) percentages of unadulterated milk. The cost to human health and well being upon consumption of this synthetic milk is huge: it deprives consumers of the vital nutrients otherwise obtained from unadulterated milk while at the same time being harmful to health. Currently used testing based on fat and lactometer levels used to detect adulterated milk obviously fail in this scenario. Thus there is an urgent need for developing other measuring techniques to address and overcome this major health concern. For maximum societal impact the measuring platform should be cheap, easy to use, robust and precise with high sensitivity.

Prof. V. Lakshminarayan’s group at RRI has proposed a simple test that satisfies all the above requirements. The test is based on impedance measurement of the ionic constituents of normal milk vs. adulterated milk that can act as a first level screening to check for adulterated milk samples. Additionally, being a hand held device empowers the consumer to demand “on the spot” screening of milk samples.

The basic research was completed at RRI while collaborators in the Department of Electronics Systems and Engineering (DESE) design, Indian Institute of Science and the DST-National Hub for Health Care Instrumentation (NHHID) will undertake the product design and manufacture.

It is envisioned that a simple “Dip and Read” device can be made available at milk collection and distribution centers to rapidly assess for synthetic milk.


A picture of the hand held device to detect synthetic milkUntitled


SWAN-Sky Watch Array Network



Twinkle Twinkle Little star

How I wonder what you are

Shining with brilliant light

What have you got beyond my sight


From time immemorial human beings have wondered at the beautiful displays of light output by countless celestial objects in the night sky. Early attempts by astronomers at understanding the universe were confined to observations and analysis of output from objects that were visible to the human eye aided by optical telescopes. However, what the human eye can discern is just one small portion of the much larger output spectrum called the electromagnetic spectrum, which includes gamma rays, x-rays, ultraviolet, microwave and radio waves. On a fundamental level the above different forms of radiation are all the same, the difference lies in the frequency and wavelengths of oscillations. To the early astronomers the majority of the universe was literally hidden from plain sight.

We have come a long way from those early days – astronomers routinely collect light radiated by stars across most of the electromagnetic spectrum using specialized telescopes designed to collect specific frequency bands of radiation. For example astronomers use radio telescopes to study celestial objects at radio frequencies. Based on whether the radio output occurs continuously or in short bursts, celestial sources can be classified as steady state and transient. Right from the beginning radio astronomers have focused on steady state radio sources with some exceptions leading to exciting discoveries. A detailed study of the transient sky could also open up an entirely new dimension of astronomical exploration with a huge potential (which is presently difficult to quantify) for yet unanticipated discoveries of astronomical objects and phenomena. There is a need to facilitate and conduct searches and studies of fast (typically of sub-second duration) and slow transient radio radiation originating from astronomical sources. In fact studies show that transient events occur at a much higher rate than anticipated. To enable detection and proper analysis of such events requires an optimized setup that could routinely detect transient signals over a large volume of sky with required sensitivity.

Researchers at RRI have taken up this challenge by proposing Indian-SWAN (Sky Watch Array Network). SWAN is designed in such a way that it provides capabilities for reliable detection of energetic radio transients. One unique feature of SWAN is the opportunity it provides for bright and motivated students from across India to be involved directly in the realization of SWAN, including in the design, and also in the operation/usage of the setup for astronomical observations, as well as the follow-up/research. These opportunities have the potential to seed significant growth of future generations of Indian radio astronomers pursuing active research, including with future large telescopes.

Prof. Avinash Deshpande who is leading the project and is passionate about kindling interest in astronomy in the minds of young Indians says “The implicit aim is to initiate a collective effort to develop SWAN with as many of the 40+ technology and science institutes i.e. the (IIT, NIT, IISER & NISER)s, as well as some universities across India. The prospective institutes, particularly motivated people in these, will be approached for partnership. To prepare for student involvement, appropriate schools/workshops (in co-ordination with existing programs) are to be arranged to formally introduce under-grad and masters students to radio astronomy, basic concepts and advance topics/techniques, over a few weeks each year, along with hands-on experience with instrumentation. Active participation from the students in all aspects of the SWAN, including studies of astronomical sources, will be sought and explicitly encouraged/supported.”


Picture displaying one tile antenna of SWAN currently located at the Gauribidanur Radio Telescope Observatory

The more the merrier

Imagine two celestial objects – black holes – colliding and merging to form an even more massive black hole somewhere in deep space. Collisions and mergers such as these would be rather ubiquitous given the billions of black holes that probably dot our vast, perhaps somewhat cavernous Universe if you step just outside of Earth. But of course, with our limited technological prowess, probing the Universe’s mysteries remains out of reach – till early 2016, we had no way of directly detecting such a binary black hole merger.

Then on 11th February, 2016, the Advanced Laser Interferometer Gravitational-Wave Observatory (ALIGO) announced GW 150914, a binary black hole merger occurring on 14th September 2015 that resulted in the verification of General Relativity’s last remaining prediction – the existence of gravitational waves, powerful enough to distort our familiar four-dimensional space-time fabric. The masses involved were immense, the resultant black hole super-massive, and the energy radiated was more than the combined power of all light radiated by all stars in the thus-far observed Universe.

Physicists will tell you though that such a violent astrophysical event can hardly ever have only one tell-tale signature. 0.4 seconds after GW 150914, the Fermi Gamma-ray Burst Monitor (GBM) mounted on the Fermi Gamma-ray Space Telescope (FGST), had recorded a short gamma-ray burst (GRB).

Short GRBs are sources of extremely large amounts of energy concentrated within a very short interval of time and energetic enough to emit as much energy as our Sun does in 10 billion years. GRBs arise typically from a supernova explosion by way of which a high-mass star collapses to form a neutron star or a black hole, or perhaps from two colliding neutron stars.

Gamma-ray bursts consist of gamma-rays which are a form of electromagnetic radiation similar to X-rays, visible light or radio waves, the only difference being their underlying wavelength and the energy they bear. Along with gamma-rays though, GRBs dispense energy also in the form of highly accelerated protons. And where there are accelerated protons, can neutrinos be very far behind?

Neutrinos are uncharged, almost massless, almost non-interacting elementary particles that are everywhere around us. Forget your wonder at the dust particles you see floating in that sunbeam. A trillion neutrinos from the Sun pass through our eyes every second! Being almost non-interacting, they pass unhindered through normal matter. You need a billion kilometers of lead to detect a neutrino! But latest detectors such as the IceCube Neutrino Observatory in South Pole with its thousands of ultra-sensitive sensors buried under a cubic kilometer of dense Antarctic ice are catching up with these elusive particles.

GRBs may produce copious amounts of high-energy neutrinos (HENs). So what information do the HENs possibly associated with the GRB that was recorded 0.4s after GW150914 within the localization uncertainty limits of the GBM give us? That was precisely the question that a team of researchers from Raman Research Institute, Bengaluru, University of Johannesburg and Pennsylvania State University asked. They first theoretically modelled the GBM observation to find the amount of HENs that IceCube should detect from this short GRB and could find none. But this non-result placed an upper limit on the total energy released by this short GRB, which, incidentally turned out to be very small compared to that emitted in gravitational waves by GW150914.

No matter though, because combined HEN, GW and electromagnetic radiation studies of the Universe are here to stay – the more the merrier as the saying goes.

Dr. Nayantara Gupta, RRI says “We look forward to more instances of coinciding detections, because by combining such observations and theoretical modelling, we can learn not only from what we detect, but even what we do not.”

About the author and work:

Dr. Nayantara Gupta is an Associate Professor at the Department of Astronomy and Astrophysics at Raman Research Institute, Bengaluru. Contact: <>. For the publication see