SCIENCE & TECHNOLOGY AFFAIRS OCTOBER 2016
- Uranus may have two more moons: Study
Uranus may have two tiny, previously undiscovered moons orbiting near two of the planet’s rings, researchers said, after analysing data from NASA’s Voyager 2 spacecraft.
Rob Chancia, a doctoral student at the University of Idaho in the U.S., saw key patterns while examining images of Uranus’ rings, said the study published in Astronomical Journal.
He noticed the amount of ring material on the edge of the alpha ring — one of the brightest of Uranus’ multiple rings — varied periodically. A similar, even more promising pattern occurred in the same part of the neighbouring beta ring.
Researchers analysed radio occultations — made when Voyager 2 sent radio waves through the rings to be detected back on Earth — and stellar occultations, made when the spacecraft measured the light of background stars shining through the rings, which helps show how much material they contain.
They found the pattern in Uranus’ rings was similar to moon-related structures in Saturn’s rings called moonlet wakes. The researchers estimate the hypothesised moonlets in Uranus’ rings would be four to 14 kilometres in diameter — as small as some identified moons of Saturn, but smaller than any of Uranus’ known moons. Uranian moons are especially hard to spot because their surfaces are covered in dark material.
The moonlets, if they exist, may be acting as “shepherd” moons, helping to keep the rings from spreading out. Two of Uranus’ 27 known moons, Ophelia and Cordelia, act as shepherds to Uranus’ epsilon ring. - China launches its longest ever manned mission to space
China on 16th October launched spacecraft in longest-ever manned mission, taking two astronauts into orbit. They will spend a month aboard an experimental space laboratory that is part of a broader plan to have a permanent manned space station in service around 2022. The Shenzhou 11 blasted off on a Long March rocket from the remote launch site in Jiuquan, in the Gobi desert, in images carried live on state television.
- Scientists produce electricity from water without using energy
In a major breakthrough, scientists at Delhi’s National Physical Laboratory (NPL) have developed a novel way of producing electricity from water at room temperature without using any power or chemicals.
A team led by Dr. R.K. Kotnala used nanoporous magnesium ferrite to split water into hydronium (H3O) and hydroxide (OH) ions and used silver and zinc as electrodes to make a cell that produces electricity.
The hydroelectric cell that uses magnesium ferrite of 1 sq. inch size produces 8 mA current and 0.98 volt. According to a paper published in the International Journal of Energy Research, magnesium ferrite of 2-inch diameter produces 82 mA current and 0.9 volt. Now, the hydroelectric cell material design has been improved and a 2-inch diameter material generates 150 mA current and 0.9 V.
Since magnesium has high affinity for hydroxide, it spontaneously splits or dissociates water into hydronium and hydroxide ions. The hydronium ions get trapped inside the nanopores of magnesium ferrite and generate an electric field. The electric field helps in further dissociation of water.
Magnesium ferrite is made as an oxygen-deficient material and has plenty of oxygen vacancies. To further enhance the activity of magnesium ferrite, about 20 per cent of magnesium is replaced with lithium.
The substitution of lithium at magnesium site increases the sensitivity of magnesium ferrite. This is helpful in dissociating water at room temperature as the electrons get trapped in the oxygen deficient sites. - Indian-origin scientist creates 'real' 3D hands in laboratory
An Indian-American researcher and his team have created life-size 3D hand models, complete with fingerprints, using a high-resolution 3D printer that can produce the same ridges and valleys as a real finger. Like any optical device, fingerprint and hand scanners need to be calibrated, but currently there is no standard method for doing so.
This is the first time a whole hand 3D target has been created to calibrate fingerprint scanners. As a byproduct of this research, realized a fake 3D hand, essentially a spoof, with someone's fingerprints, could potentially allow a crook to steal the person's identity to break into a vault, contaminate a crime scene or enter the country illegally.
Jain and his biometrics team were studying how to test and calibrate fingerprint scanners commonly used across the globe at police departments, airport immigration counters, banks and even amusement parks. To test the scanners, they created life-size 3D hand models complete with all five fingerprints.
The study aims to design and develop standard models and procedures for consistent and reliable evaluation of fingerprint readers and is funded by the National Institute of Standards and Technology (NIST). The FBI, CIA, military and manufacturers will all be interested in this project. Along with Jain and Paulter, the study was co-authored by Sunpreet Arora, MSU doctoral student. - Over-drinking may cause fatal water intoxication: study
Drinking too much water may cause potentially fatal water intoxication, claims a new study which has for the first time identified the mechanism that regulates fluid intake in the human body and stops us from over-drinking.
The study, led by researchers from Monash University in Australia, challenges the popular idea that we should drink eight glasses of water a day for good health.
It showed that a 'swallowing inhibition' is activated by the brain after excess liquid is consumed, helping maintain tightly calibrated volumes of water in the body.
The researchers asked participants to rate the amount of effort required to swallow water under two conditions; following exercise when they were thirsty and later after they were persuaded to drink an excess amount of water. The results showed a three-fold increase in effort after over-drinking.
Researchers used functional magnetic resonance imaging (fMRI) to measure activity in various parts of the brain, focusing on the brief period just before swallowing.
The fMRI showed the right prefrontal areas of the brain were much more active when participants were trying to swallow with much effort, suggesting the frontal cortex steps in to override the swallowing inhibition so drinking could occur according to the researcher's instructions.
Drinking too much water in the body puts it in danger of water intoxication or hyponatremia, when vital levels of sodium in the blood become abnormally low potentially causing symptoms ranging from lethargy and nausea to convulsions and coma.
Elderly people, however, often did not drink enough and should watch their intake of fluids, said Farrell. The study was published in the journal Proceedings of the National Academy of Sciences. - New universal flu vaccine to prevent global pandemics
Scientists have designed a new generation of universal flu vaccines that protects against majority of the known viral strains and help prevent future global pandemics that could kill millions.
The researchers devised two universal vaccines. One can protect against up to 88 per cent of known flu strains worldwide in a single shot, spelling the end of the winter flu season. Another vaccine covers 95 per cent of known US influenza strains.
According to the World Health Organisation (WHO), annual flu epidemics are estimated to cause up to half a million deaths globally. - ISRO's GSAT-18 launched at Koururu
GSAT-18, built by the Indian Space Research Organisation (ISRO), aims at providing telecommunications services for the country, was launched on 6th October from the European launcher Ariane-5 VA-231.
GSAT-18 is the 20th satellite from ISRO to be launched by the European space agency and the mission is the 280th for Arianespace launcher family. ISRO, which has been dependent on Ariane-5 rocket for carrying its heavier satellites, is developing GSLV Mk III for this purpose.
Weighing 3,404 kg at lift-off, GSAT-18 carries 48 communication transponders to provide services in Normal C-band, Upper Extended C-band and Ku-bands of the frequency spectrum.
Designed to provide continuity of services on operational satellites in these bands, GSAT-18 with a mission life of about 15 years, carries Ku-band beacon as well to help in accurately pointing ground antennas towards the satellite.
With GSAT-18’s injection into GTO, ISRO’s Master Control Facility (MCF) at Hassan in Karnataka takes control of the satellite and will perform the initial orbit raising manoeuvres using the Liquid Apogee Motor (LAM) of the satellite, placing it in a circular Geostationary Orbit.
Following this, the deployment of appendages such as the solar panels and antennas as well as three axis stabilisation of the satellite will be performed, and GSAT-18 will be positioned at 74 deg East longitude and co-located with other operational satellites
GSAT-18s co-passenger Sky Muster II, built by SSL (Space Systems Loral) in Palo Alto, California, is aimed at bridging the digital divide, especially in the rural and isolated regions of Australia.
No comments:
Post a Comment