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Friday, 10 October 2014

Mars Orbiter Mission shifts orbit to take cover from Siding Spring

India's Mars orbiter has sent a picture of regional dust storm activities over the northern hemisphere of the Red Planet, Isro said on Monday.
"Regional dust storm activities over northern hemisphere of Mars - captured by Mars Color Camera on-board Mars Orbiter Mission (MOM)", Bangalore-headquartered Indian Space Research Organisation (Isro) said on its official Facebook page with a picture.
It said the image was taken from an altitude of 74,500km from the surface of Mars.
MOM spacecraft had sent its first images of the planet on Thursday, a day after creating history by becoming the only such endeavour so far to have met with success on the maiden attempt.
The Mangalyaan Mars Orbiter Mission aims to study the Martian surface and mineral composition and scan its atmosphere for methane, an indicator of life.
The spacecraft is equipped with five instruments, including a sensor to track methane or marsh gas, a colour camera and a thermal-imaging spectrometer to map the surface and mineral wealth of the planet.
The Rs. 450-crore MOM is the cheapest interplanetary mission. India is the first country to reach Mars in its very first attempt. European, American and Russian probes have managed to orbit or land on the planet, but after several attempts.
The orbiter will keep moving in an elliptical path for at least 6 months with its instruments sending their gleanings back home.
The spacecraft was launched on its 9-month-long odyssey on a homegrown PSLV rocket from Sriharikota in Andhra Pradesh on November 5, last year. It had escaped the Earth's gravitational field on December 1 and was placed in the Martian orbit on September 24.

World's smallest microphone is made from a single molecule

A team of scientists from Lund University in Sweden has figured out how to turn a single molecule into a microphone by making it capable of detecting the vibrations produced by sound waves.
This minuscule microphone works by embedding a single molecule of a substance called dibenzoterrylene (DBT) in a tiny crystal of a hydrocarbon material called anthracene. When the crystal is exposed to sound waves, the DBT molecule is disturbed by the vibrations, and it vibrates in response. 
"This movement changes the interaction between the electron clouds of DBT and anthracene, which ultimately result in a slight shift in DBT's fluorescence,” explains Sarah Zhang at Gizmodo. "By tracking the fluorescence of just a single molecule of DBT, the scientists could track the frequency of the sound."
Right now, the mini-microphone only works in a very specific environment - the surrounding temperature must always be super-cold because warm temperatures can cause the molecule to move around too much - but the team is now working on making it more flexible. They don’t see their device being included in any high-tech spy kits any time soon, but they do intend for it to be used in physics labs to spot nanoscale movements in both chemical and biological systems. “A tiny sensor for tiny things,” as Zhang puts it.

Scientists have created the most effective “invisibility cloak” so far, and you can make one for $100

Created by scientists at the University of Rochester in New York, the device can hide large objects from sight using cheap and readily available lenses.
“There’ve been many high tech approaches to cloaking and the basic idea behind these is to take light and have it pass around something as if it isn’t there, often using high-tech or exotic materials,” said John Howell, a professor of physics at the University of Rochester in a press release.
But while it works like an invisibility cloak, it looks more like something your optometrist would use to check your eyes - and when something is placed behind the layered lens, it disappears from view, leaving the background untouched.
“This is the first device that we know of that can do three-dimensional, continuously multidirectional cloaking, which works for transmitting rays in the visible spectrum,” graduate student Joseph Choi, who helped develop the technology with Howell, said in the release.
Previously, scientists had struggled to hide objects from varying angles, so they would be masked when you looked at them from straight on, but would be visible again when you moved your head. Now this new device has been used to cloak a hand, a face and a ruler from all angles. And the applications are pretty incredible - for example, a doctor could look through the lens and see the organs he was operating on below his hand. They could also let drivers see through their vehicle to their blind spot. Not to mention the fact that it can make you invisible, which is just freaking awesome.
The device can also be scaled up depending on the size of the lens, and would allow large objects to be cloaked. It also works for the whole visible spectrum of light, which means there are no limitations to what it can block.
It works by using four separate lenses with different focal lengths. By carefully calculating the distance between these lenses, Choi and Howell managed to bend the light around an object. They've submitted their results to the journal Optics Express, and the paper is also available
The team has now released instructions and equations that will help people build a similar device at home for around $100.

Thursday, 13 March 2014

Kidneys produce an active form of vitamin D

Today is World Kidney Day! Kidneys produce an active form of vitamin D, remove waste products from the body and control the production of red blood cells. Here are more interesting facts about kidneys.

→ Each kidney has about 1 million nephrons.
→ Kidneys represent 0.5% of the body’s entire weight.
→ Your kidneys clean about 1 litre of blood every minute.
→ Kidneys filter about 2 litres of urine every day.
→ Kidneys receive 20 to 25% of all the blood pumped by the heart.