What will be the India-based Neutrino Observatory’s impact?
The INO will be like a 2-inch hole made to insert a pipe through a
10-foot-high wall; it will not affect the stability of the hill
In a landmark move, the Government of India’s Union Cabinet recently
approved the India-based Neutrino Observatory project. Coming soon after
the approval of the 30-metre telescope which will be located in Hawaii,
this decision will cause India to step into big fundamental science. “A
pioneer in the field of neutrino science, India was a world leader in
1965. In the mid-1990s, with the closing of the Kolar Gold Fields which
was the site of the experiments, experimental neutrino research in India
came to a halt, and the INO is expected to revive the lost advantage,”
says Prof. G. Rajasekaran of the Institute of Mathematical Sciences,
Chennai, a founder member of the INO.
The three types of neutrinos, which were initially thought to be mass-less, are now believed to have a small mass.
This was shown by observations of neutrino oscillation, which is a
phenomenon by which one type of neutrino transforms into another.
There is a hierarchy among the masses of these three types of neutrino
and the experiments at the INO will study this mass ordering using a
magnetised iron calorimeter (ICAL). The ICAL is a massive detector which
will be made of iron — 50,000 tonnes of it! The project will be housed
in the 63 acres of land, about 2 km away from the settlement, in the
Bodi West Hills about 100 km from Madurai, Tamil Nadu.
One might wonder at the need for such a massive detector and for
drilling underground. The reason is that the neutrinos interact very
weakly with the surroundings. We are all being washed by a stream of
neutrinos every passing minute as they just pass through us without
leaving a trace. Since they interact so weakly, detecting them over
other interactions is impossible. We need to have a barrier of at least 1
km of earth to block out other radiation and particles, such as muons
from cosmic rays. This is the reason scientists are now going
underground. They will construct a tunnel at a depth of 1,300 metres
below the peak and which is 2 km by 7.5m by 7.5m. This will lead to a
chamber that will house the detector.
Questions have been raised as to whether this tunnel will harm the
mountain. D. Indumathi, physicist and outreach co-ordinator of INO says,
“This is exactly like making a 2-inch hole to insert a pipe through a
10-foot-high wall. It will not affect the stability of the hill.” About
the ecological impact of the construction process, Dr, Indumathi says,
“There will be hardly any disturbance after the construction period.
During construction, we will take a lot of precautions and proceed in a
controlled manner. Controlled blasting of the rock will last a few
seconds, twice a day. At a few hundred metres from the site, this will
produce a ground vibration less than 1 mm per sec.”
The members of INO had to deal with many more questions such as the
effect of the construction on distant dams and the impact of the
development on the villagers, and, according to her, detailed answers to
questions on the impact of various aspects of the project are outlined
in the INO website.
“In Idukki itself, there are more than 200 quarries, which are working without impacting the dam.
Even the Chennai Metro Rail project can dig just metres under the
buildings without damaging them because of advances in technology,” she
says.
While experiments around the world are being set up in the South Pole,
on top of mountains and even in outer space, big basic science projects
are still new in India. The INO’s project director Naba Mondal says,
“This will be the largest experimental facility to come up in the
country and students will get a chance to work with cutting edge
technology and build sophisticated instruments.
It will be a boon for students all over the country, especially Tamil Nadu.”
For instance, S. Pethuraj, who passed out of Madurai Kamaraj University,
has joined the INO’s PhD programme at TIFR, Mumbai. “Meeting the INO
scientists at the university was inspiring, and the exposure I get at
TIFR is of a very high level,” he says.
Scientists find promising new antibiotic
The bacterium, Eleftheria terrae, yielded an entirely new sort of antibiotic
Using a novel technique to culture soil bacteria that
previously could not be grown in the laboratory, a team of U.S.
scientists has isolated a promising new antibiotic to which resistance
may not develop easily.
The research, published this week in Nature,
comes at a time when there is growing alarm both at the spread of
antibiotic-resistant microbes and the failure to find new classes of
antibiotics in recent decades.
During the ‘golden
age of antibiotics’ from about 1940 to around 1960, scientists were able
to find a number of new drugs by carefully screening soil bacteria,
looking for anti-microbial activity. However, they were able to examine
only bacteria that could be grown in the laboratory and more than 99 per
cent of the bacterial species in the soil resisted such efforts, with
the result that such leads eventually petered out.
Dr.
Kim Lewis, director of the Antimicrobial Discovery Center at the
Northeastern University in the U.S., and colleagues used an ‘isolation
chip’ (iChip) developed at the university to culture previously
uncultivable soil bacteria.
This chip has a larger
number of tiny chambers to hold individual bacterial cells. Covered with
semi-permeable membranes, the chip could be then placed in the soil,
allowing vital nutrients and growth factors to diffuse into its
chambers.
With the iChip, the scientists could grow 10,000 bacterial strains. The extract from one such bacterium, provisionally named Eleftheria terrae, yielded an entirely new sort of antibiotic, teixobactin.
Laboratory
tests showed that this molecule was effective against many human
pathogens, including drug-resistant ones, that come in the category of
gram-positive bacteria.
The drug was “exquisitely
active” against a number of hard-to-deal-with bugs, said Dr. Lewis
during a press briefing. It might also offer a single-drug therapy for
tuberculosis, which currently required prolonged treatment with a
multi-drug combination.
Teixobactin worked by binding
to highly conserved precursors that bacteria used to build their cell
walls, according to Tanja Schneider of the University of Bonn in
Germany, one of the co-authors of the Nature paper, whose team worked on the drug’s mode of action.
Even when the susceptible forms of the bacterium Staphylococcus aureus and the one that causes tuberculosis, Mycobacterium tuberculosis, were grown in the presence of low doses of the antibiotic, drug-resistant mutants could not be found.
Nor did such mutants evolve after S. aureus cultures were repeatedly exposed to sub-lethal doses of the antibiotic over several days.
It
could be that resistance was less likely to develop against antibiotics
that targeted precursors for cell wall synthesis, observed Gerard
Wright of McMaster University, Canada, in a commentary published in the
same journal.
When, on the other hand, the
antibiotic acted on bacterial proteins, genes for those proteins could
mutate and produce resistance.
Resistance against
vancomycin, which too binds to cell-wall precursors, did not emerge in
the clinic till almost four decades after its discovery, he pointed out.
Such resistance came about through genes for a self-protective
mechanism used by vancomycin-producing bacteria getting transferred to
pathogenic strains.
The bacterium producing
teixobactin, on the other hand, was protected by an outer membrane, and
so there was no self-resistance mechanism that could be passed on, he
noted.
The drug could be ready to go into clinical trials two years from now, according to Dr. Lewis.
Embankments are sinking Bangladesh’s islands
Bangladesh’s estuarine islands are sinking, and
ironically, this could owe to embankments built to protect them from
tidal erosion. Some islands have sunk by as much as 1.5 metres in the
last 50 years, says a study published recently in the journal Nature Climate Change.
The
over 50 large islands in southwest Bangladesh, once forested but now
primarily rice growing, were embanked in the 1960s and 1970s to protect
them against tidal and storm-surge inundation. But these earthen
embankments, while buffering them against floods, have also prevented
the deposition of sediment that helps maintain an elevation in this
area.
The loss of elevation was felt most
significantly during the 2009 cyclone Alia when large areas of land were
left inundated for upto two years. “Despite sustained human suffering
during this time, the newly reconnected landscape received tens of
centimetres of tidally deposited sediment, equivalent to decades’ worth
of normal sedimentation,” says the paper. Deforestation and a
regionally increased tidal range have contributed to the phenomenon, say
the researchers from Vanderbilt University, Tennessee, U.S. and Khulna
University, Bangladesh. Interestingly, while these islands in the
Ganges–Brahmaputra river delta are fast submerging, putting millions of
inhabitants at risk of flooding, the neighbouring Sundarbans mangroves
are stable from their natural shield of vegetation, the paper adds.
Researchers
used GPS and a theodolite survey of land elevations at an island called
Polder-32 in southwest Bangladesh and compared it with the Sundarbans.
They found that the mean elevation of Polder-32 is 1.15 metres lower
than Sundarbans.
The study therefore implicates
“direct human modification of the environment” and not global sea-level
rise as the most important agent of change in the western Ganges
Brahmaputra tidal delta plain, says the paper.
“The
striking contrast between the tidal inundation patterns of these
landscapes highlights the impact of sediment starvation and the
historical loss of elevation, which has severely exacerbated the effects
of tidal inundation,” notes the paper.
However it
is possible to recover some of the lost ground, say the authors adding
that “controlled breaching of embankments” can restore elevation and
relieve environmental problems. “The silver lining for Bangladesh and
the delta system remains the one billion tons of river sediment that may
be effectively dispersed onto the landscape to alleviate elevation
deficits. On the basis of our observations, a feasible management
strategy from the physical-science perspective may be to systematically
breach embankment sections to facilitate sediment delivery and elevation
recovery.”
Hubble captures images of Eagle Nebula's 'Pillars of Creation'
Reuters
By comparing the 1995 and 2014 pictures, astronomers noticed a
lengthening of a narrow jet-like feature that may have been ejected from
a newly forming star. Over the intervening 19 years, this jet has
stretched farther into space, across an additional 60 billion miles, at
an estimated speed of about 450,000 miles per hour, according to a NASA
news release. Photo credits: NASA
The NASA/ESA Hubble Space Telescope has revisited the famous Eagle
Nebula's Pillars of Creation and has captured high-definition images.
The telescope had earlier captured the three impressive towers of gas
and dust in 1995, which revealed never-before-seen details in the giant
columns and now the telescope is kickstarting its 25th year in orbit
with an even clearer, and more stunning, image of these beautiful
structures.
The captured image is part of the Eagle Nebula, otherwise known as
Messier 16 and although such features are not uncommon in star-forming
regions, the Messier 16 structures are by far the most photogenic and
evocative ever captured.
The recent images show the famous pillars, capturing the multi-coloured
glow of gas clouds, wispy tendrils of dark cosmic dust, and the
rust-coloured elephants' trunks with the newer Wide Field Camera 3,
installed in 2009.
In addition to this new visible-light image, Hubble has also produced a
bonus image, which is taken in infrared light, penetrating much of the
obscuring dust and gas and unveils a more unfamiliar view of the
pillars, transforming them into wispy silhouettes set against a
background peppered with stars.
Although the original image was dubbed the "Pillars of Creation", this
new image hints that they are also pillars of destruction. The dust and
gas in these pillars is seared by intense radiation from the young stars
forming within them, and eroded by strong winds from massive nearby
stars. The ghostly bluish haze around the dense edges of the pillars in
the visible-light view is material that is being heated by bright young
stars and evaporating away.
The infrared image shows that the reason the pillars exist is because
the very ends of them are dense, and they shadow the gas below them,
creating the long, pillar-like structures and the gas in between the
pillars has long since been blown away by the winds from a nearby star
cluster.
8 new planets found in ‘Goldilocks zone’
Astronomers with the Harvard-Smithsonian Center for Astrophysics (CfA)
have discovered eight new planets within the so-called Goldilocks — or
habitable — zone of their stars.
To be considered habitable, exoplanets must orbit within a distance of
their stars in which liquid water can exist on the planet’s surface,
receiving about as much sunlight as Earth.
“Most of these planets have a good chance of being rocky, like Earth,”
lead author Guillermo Torres of the CfA said in a release.
The discoveries of Kepler-438b and Kepler-442b are the latest in several
advancements scientists have made to find signs of possible life in the
universe.
At a panel held last summer at NASA headquarters in Washington,
astronomers said they were “very close in terms of technology and
science to actually finding the other Earth.”
That’s due in part to the Kepler Space Telescope. The planet-hunting
Kepler probe, launched in 2009, finds planets by looking for dips in the
brightness of a star as a planet transits, or crosses, in front of that
star.
Christine Pulliam of CfA said the team of scientists monitored data from
more than 160,000 stars, which led them to the eight new planets.
The couple most like Earth, Kepler-438b and Kepler-442b, both orbit red
dwarf stars, which are cooler and smaller than the Earth’s sun.
Kepler—438b’s diameter is 12 per cent bigger than Earth and has a 70 per
cent chance of being rocky, which means the surface of the planet
appears to be like Earth’s.
Kepler—442b is about one-third larger than Earth with a 60 per cent
chance of being rocky. Scientists give it a 97 per cent chance of being
in the habitable zone, but caution that the estimations aren’t certain.
“We don’t know for sure whether any of the planets in our sample are
truly habitable,” second author David Kipping of the CfA said in a
release.
“All we can say is that they’re promising candidates.”
NASA robot can explore extraterrestrial volcanoes
The US space agency has developed a robot that is enabling researchers to put together a 3D map of a fissure — a crack that erupts magma — that is now inactive on Hawaii’s Kilauea volcano.
The research has implications for extraterrestrial volcanoes.
On both Earth and Mars, fissures are the most common physical features from which magma erupts.
“This is probably also true for the previously active volcanoes on the moon, Mercury, Enceladus and Europa, although the mechanism of volcanic eruption — whether past or present — on these other planetary bodies is unknown,” said Carolyn Parcheta, postdoctoral fellow at NASA’s Jet Propulsion Laboratory (JPL) who worked with the robot called VolcanoBot 1 in Hawaii in May 2014.
While VolcanoBot 1 was tested at Kilauea volcano in Hawaii, a lighter, smaller VolcanoBot 2 will be tested this year.
Ms. Parcheta and her co-advisor Aaron Parness, robotics researcher at JPL, are developing robots that can get into crevices where humans would not be able to go, gaining new insights about these wondrous geological features.
“We do not know exactly how volcanoes erupt. We have models but they are all very, very simplified. This project aims to help make those models more realistic,” Ms. Parcheta noted.
VolcanoBot 1 was able to descend to depths of 82 feet in two locations on the fissure, although it could have gone deeper with a longer tether, as the bottom was not reached on either descent.
“In order to eventually understand how to predict eruptions and conduct hazard assessments, we need to understand how the magma is coming out of the ground. This is the first time we have been able to measure it directly, from the inside, to centimetre-scale accuracy,” Ms. Parcheta pointed out.
The team plans to test VolcanoBot 2 at Kilauea in early March this year.
