India successfully launches its surveillance satellite – RISAT-1

PSLV-C19 lifts off with RISAT-1 satellite (Image courtesy - ISRO)

India’s workhorse launch vehicle, PSLV, put the country’s first microwave radar imaging satellite – RISAT-1 – into orbit, the 20th successful launch since its inception in 1993.

RISAT-1 is the heaviest satellite with 1850 kg launched by PSLV. It was injected at a point 480 kms above the earth. Though the avowed applications of the satellite are in agriculture and management of natural disasters, its cloud penetration and day and night imaging capability will provide the country an eye from the sky. Over the next three days, its satellite onboard propulsion system will raise the attitude to 536 kms above the earth, where it will circle the planet over the poles 14 times a day.

The lift off was accomplished at 5.47 am on Thursday (April 26) from Indian Space Research Organisation’s Satish Dhavan Space Centre at Sriharikota, 80 km from the southern city of Chennai.

“The twentieth consecutive successful launch of the PSLV is an important milestone in our space programme and is testimony to ISRO’s mastery of the complex launch vehicle technology,” said Prime Minister Dr. Manmohan Singh in a congratulatory message to the ISRO scientists. “I have no doubt that RISAT-1’s all-weather, day-night imaging ability will significantly contribute to the nation’s remote sensing capabilities.”

PSLV-C19-PS1- nozzle-end segment arrives at the launchpad (Image courtesy- ISRO)

Addressing a post-launch press conference, ISRO Chairman Dr. K. Radhakrishnan said the space agency plans at least three more satellite launches from Sriharikota, including another PSLV flight in August, carrying six satellites. He said, ISRO will also try to launch a Geosynchronous Satellite Launch Vehicle rocket with an indigenous cryogenic engine later in the year.

India has emerged a world leader in space technology, with the largest constellation of remote sensing satellites providing imagery in a variety of spatial resolutions from more than a metre ranging upto 500 meters. It has 11 remote sensing/earth observation satellites currently in the space.

Warm ocean currents cause melting of Antarctica ice

Ice Shelf in Antarctica (Image courtesy - BAS)

Researchers have established, warm ocean currents cause melting of ice shelves in the Antarctica region.  An international team of scientists led by British Antarctic Survey used new techniques to differentiate, for the first time, between the two known causes of melting of ice shelves – warm ocean currents attacking the underside and warm air melting from above. The finding brings scientists a step closer to providing reliable projections of future sea-level rise.

Using a laser instrument mounted on NASA’s ICESat satellite to map the changing thickness of almost all the floating ice shelves around Antarctica, researchers revealed the pattern of ice-shelf melt across the continent and found 20 of the 54 mapped ice shelves melted by global warming, mostly in the western part of Antarctica.

Antarctic Ice Shelf (Image courtesy: BAS)

“In most places in Antarctica, we can’t explain the ice-shelf thinning through melting of snow at the surface, so it has to be driven by warm ocean currents melting them from below,” said Dr Hamish Pritchard from British Antarctic Survey.

“We’ve looked all around the Antarctic coast and we see a clear pattern: in all the cases where ice shelves are being melted by the ocean, the inland glaciers are speeding up. It’s this glacier acceleration that’s responsible for most of the increase in ice loss from the continent and this is contributing to sea-level rise.”

Studies have shown that Antarctic winds have changed because of changes in climate, and that this has affected the strength and direction of ocean currents. As a result warm water is funneled beneath the floating ice. These studies therefore suggest Antarctica’s glaciers are responding rapidly to a changing climate, said Dr Pritchard.

NASA’s ICESat satellite (Image courtesy: BAS)

A different picture is seen on the eastern Antarctic Peninsula (the long stretch of land pointing towards South America), where warm summer winds directly melt the snow on the ice-shelf surfaces. Both patterns, of widespread ocean-driven melting and summer melting on the Antarctic Peninsula are attributed to Antarctica’s changing wind patterns.

The research is part of international efforts to improve understanding of the interactions between ice and climate in order to improve the reliability of sea-level rise projections.

“This study shows very clearly why the Antarctic ice sheet is currently losing ice, which is a major advance.  But the real significance is that it also shows the key to predicting how the ice sheet will change in the future is in understanding the oceans. Perhaps we should not only be looking to the skies above Antarctica, but also into the surrounding oceans,” said Professor David Vaughan, leader of ice2sea – a major EU-funded FP7 programme

The study was carried out by an international team from British Antarctic Survey, Utrecht University, Scripps Institution of Oceanography and Earth & Space Research in Corvallis, Oregon. NASA’s ICESat – Ice, Cloud and Land Elevation Satellite – measurements were collected during the period 2003 – 2008 to detect changes in ice-shelf thickness through time.

India fares poorly in measles control; worse than sub-Saharan countries: WHO

India accounts for almost half the global measles mortality, according to results from a model surveillance data published by British medical journal  The Lancet. India accounted for 47 per cent of estimated global measles mortality of 139,300 in 2010, while it was 36 per cent in the African region.

On the global level, there was a marked decrease in the mortality – 74 per cent from 535,300 deaths in 2000. According to the study, ‘delayed implementation of accelerated disease control in India and continued outbreaks in Africa’ stalled efforts to achieve the 2010 global measles mortality reduction goal set by World Health Organisation and its partners. ‘Intensified control measures and renewed political and financial commitment’ are needed to achieve the targets.

“A three-quarter drop in measles deaths worldwide shows just how effective well-run vaccination programmes can be,” said Dr. Margaret Chan, Director General of WHO. “Now we need to take the next logical step and vaccinate children against rubella too.”

Sub-Saharan Africa made the most progress with an 85 per cent drop in measles deaths between 2000 and 2010, according to the study. As a whole, the African region account for 36 per cent of global measles mortality in 2010, down from 63 per cent in 2000. India’s small decline in measles mortality (26 per cent) led to an increase in the country’s share of global measles mortality from 16 per cent in 2000 to 47 per cent in 2010. In the remaining 10 countries of the WHO southeast Asia region, the mortality decreased by 78 per cent during 2000-10.

Measles remains widespread in India because of delayed implementation of supplemental immunization activities (SIA) (i.e., mass vaccination campaigns aimed at immunizing 100 of a predefined population within several days or weeks) and restricted improvement in measles containing vaccine coverage.  If India wants to substantially reduce measles mortality by 2015, it should undertake planned immunization activities targeting 134 million children and the introduction of a routine second dose in some states during 2011-13, says experts.

“Recent measles outbreaks have affected children in the world unevenly, with the poorest and youngest children the most at risk of death or disability,” said UNICEF Executive Director Anthony Lake. “This new Strategic Plan stresses that measles and rubella vaccinations must be delivered to children deep in the poorest and hardest to reach communities.”

The new Plan presents a five-pronged strategy to cut global measles deaths by at least 95 per cent by 2015 compared with 2000 levels and to achieve measles and rubella elimination in at least five WHO regions by 2020. The strategies include:

  • high vaccination coverage;
  • monitoring spread of disease using laboratory-backed surveillance;
  • outbreak preparedness and response and measles case management;
  • communication and community engagement; and
  • research and development.

“Measles continues to kill children around the world and rubella is the leading infectious cause of congenital malformations in newborn infants; these are avoidable tragedies,” says Thomas R. Frieden, Director of Centres for Disease Control and Prevention Administrator, USA. “This new plan outlines strategies we know work. It is time to partner with key countries to implement the plan in order to save our children from these terrible diseases.”

Measles is one of the most infectious diseases known to humankind and an important cause of death and disability among children worldwide. Those unvaccinated against the disease are at risk of severe health complications such as pneumonia, diarrhoea, and encephalitis and blindness. The disease can be fatal. The vast majority of measles deaths occur in developing countries.

Rubella, transmitted through airborne droplets, is generally a mild illness. But when a pregnant woman becomes infected, particularly during the first trimester of pregnancy, serious consequences can occur including miscarriages, still births, and infants born with birth defects known as Congenital Rubella Syndrome (CRS). The most common congenital defects include lifelong heart problems, deafness or blindness (cataracts). An estimated 112 000 cases of CRS occur each year and are preventable through vaccination. (Image courtesy: Wikimedia)

India to launch its first surveillance satellite on April 26

Risat1 undergoing final checks (Image courtesy: ISRO)

India’s space agency, ISRO, has commenced countdown for the launch of  country’s first indigenously-built spy/surveillance satellite.

The launch is scheduled for early Thursday (April 26) from Sriharikota, 80 kilmoeters from the southern city of Chennai.

“The 71-hour countdown commenced at 06:47 hours today (April 23, 2012). During the Countdown, propellant-filling operations of the liquid propellant second stage (PS2) and fourth stage (PS4) of the launch vehicle will be carried out. Besides, mandatory checks on the launch vehicle and spacecraft will be carried out,” said a press release by ISRO.

PSLV-C19 (Image courtesy: ISRO)

India’s launch vehicle PSLV-C19  would inject the 1,858 kg RISAT-1 satellite into an orbit of 480 km altitude at an inclination of 97.552 degree. The satellite will be put in its final orbital configuration at 536 km altitude using thrusters onboard the satellite.

Also, charging of batteries and pressurisation of propellant tanks onboard the satellite will be performed. Readiness of various ground systems such as tracking radar systems and communication networks will also be checked.

India has emerged a world leader in space technology, with the largest constellation of remote sensing satellites providing imagery in a variety of spatial resolutions from more than a metre ranging upto 500 meters. It has 11 remote sensing/earth observation satellites currently in the space.

India successfully test-fires its inter-continental missile Agni-V

India test-fired its strategic inter-continental ballistic missile Agni-V, joining the exclusive ICBM club of US, Russia, China, France and UK.  The solid-fuelled missile with a range of over 5000 km was tested from Wheeler Island, off Odisha coast on Thursday (April 19) morning.

The nuclear-capable, three-stage 17.5 metre tall Agni-V with a weight of 50 tonnes, will become fully operational in another two-three years after further tests and user trials.

“We have met all our mission objectives,” said Avinash Chander, Chief Controller of Missiles, Defence Research Development Organisation, DRDO.

This is the first time India has tested a three-stage, all solid-fuelled missile. Many new technologies including the state of art navigation system and carbon composite rocket motor casings were tested in the missile. All the radar telemetry and electro-optical stations along with cost, besides three ships traced the flight trajectory of the missiles and final terminal event at the impact point.

Prime Minister Dr. Manmohan Singh called DRDO Director Dr. V.K. Saraswat and his team to personally congratulate them.

“Today’s successful Agni-V test launch is another milestone in our quest to add to the credibility of our security and preparedness and to continuously explore the frontiers of science,” said Dr. Singh. “The entire nation stands together in honouring the achievements of our scientific community, who have done the country proud.”

Scientists count penguins from space

Emperor Penguin (Image Credit: British Antarctic Survey)

The number of Emperor penguins in Antarctica is far more than previously thought, according to a study by a team of scientists using satellite mapping technology.

The study led by geographer Peter Fretwell from the British Antarctic Survey (BAS) and a team of international scientists found 44 emperor penguin colonies around the cost of Antarctica, with seven previously unknown.

“We are delighted to be able to locate and identify such a large number of emperor penguins. We counted 595,000 birds, which is almost double the previous estimates of 270,000 – 350,000 birds. This is the first comprehensive census of a species taken from space,” said Fretwell.

The results provide an important benchmark for monitoring the impact of environmental change on the population of this iconic bird. The new study used a technique known as pan-sharpening to increase the resolution of the satellite imagery, which helped scientists differentiate between birds, ice, shadow and penguin poo (guano). They then used ground counts and aerial photography to calibrate the analysis. These birds breed in areas that are very difficult to study because, they are remote and often inaccessible with temperatures as low as -50 degree Celsius (minus 58 degree Fahrenheit).

Emperor Penguin and Chicks (Image courtesy: British Antarctic Survey)

“The methods we used are an enormous step forward in Antarctic ecology because we can conduct research safely and efficiently with little environmental impact, and determine estimates of an entire penguin population, said co-author Michelle LaRue from the University of Minnesota and funded by the US National Science Foundation.

BAS biologist Dr Phil Trathan, and co-author of the study, said, “Current research suggests emperor penguin colonies will be seriously affected by climate change. An accurate continent-wide census that can be easily repeated on a regular basis will help us monitor more accurately the impacts of future change on this iconic species.”

Scientists are concerned that in some regions of Antarctica, earlier spring warming is leading to loss of sea ice habitat for emperor penguins, making their northerly colonies more vulnerable to further climate change.

Dr Trathan continued, “Whilst current research leads us to expect important declines in the number of emperor penguins over the next century, the effects of warming around Antarctica are regional and uneven.  In the future we anticipate that the more southerly colonies should remain, making these important sites for further research and protection.”

The emperor is the giant of the penguin world and one of the largest of all birds. Gold patches on their ears and on the top of their chest brighten up their black heads. Emperors are the only penguin species to breed through the Antarctic winter, with temperatures as low at -50°C and winds of up to 200km (or 124 miles) per hour. They form large colonies on the sea-ice, with the female laying a single egg and passing it to the male for incubation.

This research was carried out by British Antarctic Survey in collaboration with University of Minnesota, National Science Foundation, Scripps Institution of Oceanography and the Australian Antarctic Division.

 

Fungus to control Dengue mosquitoes

Australian researchers have found fungus Beauveria bassiana could effectively kill Aedes aegypti, the mosquito responsible for spreading dengue. The results of the latest study by Jonathan Darbro of the Queensland Institute of Medical Research in Brisbane, Australia and his colleagues offer a potential alternative to pesticides to control mosquito-borne viral disease, reports The Scientist.

Yellow fever mosquito Aedes aegypti (Image courtesy: Wikimedia)

The fungus, which grows naturally in soil and is an insect parasite, is currently used to control a number of agriculture pests and recent studies have shown it may also kill dengue-carrying mosquitoes. But so far, there has only been one field study of the fungus on dengue-carrying mosquitoes, so its efficacy to temperature and humidity variations is yet to be verified.

Dengue is a viral disease transmitted by mosquitoes that infects between 50 and 100 million people annually, according to the World Health Organisation. Current control mechanisms rely heavily on insecticides, but recent reports of mosquitoes acquiring insecticide-resistance in Mexico have raised concerns about the effective management of the disease.

Darbro and his colleagues tested the fungus under laboratory and “semi-field” conditions in which the mosquitoes were housed in large cages in an area in Australia, where dengue is endemic. In the lab trials, fungal-infected mosquitoes were 30 per cent less likely to bite humans than controls and laid fewer eggs over their lifetime, similar to previous lab findings with other disease-carrying mosquitoes and other fungi. And in both the lab and semi-field trials, the fungus increased the mortality rate of infected mosquitoes by 88 per cent in the lab and between 59 to 95 per cent in the field.

“This has been an important step towards confirming what we see in the laboratory, we also see in the field,” said Darbro, noting that the fungus killed mosquitoes “equally well” in both lab and semi-field conditions, albeit more variably in the latter.

The challenge for scientists, however, is to ensure humans aren’t harmed by the fungus. But Darbro isn’t worried. While a small number of people, often with weak immune system, bas been infected by the fungus, he said, they have always been successfully treated.

Another hurdle to be overcome is developing a way successfully to infect the mosquitoes with the fungus. “That’s a million dollar question,” said Darbo. “The challenge is finding a place to put the fungus where the mosquitoes will land on it and get infected.”