World's largest optical telescope gets construction approval

The world’s largest optical telescope got the go ahead last Friday when the Hawaiian Board of Land and Natural Resources (BLNR) granted a building and operating permit for the Thirty Meter Telescope (TMT) to be sited on a plateau of Mauna Kea on the island of Hawaii. The next-generation telescope, which uses a 30-meter (98 ft) segmented mirror promises to capture images from the near-ultraviolet to the mid-infrared wavelengths with unprecedented clarity.

 


The green light on construction follows extensive hearings to determine the impact of the new observatory on the area near the volcano’s summit and how the TMT Observatory Corporation would address these issues. The permit process has been held up for two years by a series of objections to building the TMT based on environmental impact, aesthetics and possible interference with native Hawaiian cultural practices, but final approval came at a hearing on April 12 in Hilo, Hawaii, where the TMT was granted a Conservation District Use Permit.

The TMT is a wide-field, Ritchey-Chretien telescope, where the light is collected by the primary mirror, reflected back to focus on a secondary mirror, and then back again through a hole in the primary mirror to an eyepiece, camera or instrument. The distinguishing feature of the Ritchey-Chretien telescope is that both the primary and secondary mirrors are hyperboloidal. That is, their cross section follows a hyperbolic curve.

 

The 30-meter size was selected for a number of reasons. One obvious factor is that a larger telescope can capture more light and can see further and more clearly, but, according to the TMT Corporation, another reason why 30 meters was chosen is because it provides a “sweet spot” for near-infrared studies.
The mirror is not one solid piece of glass. Instead, it’s made of 492 hexagonal segments similar in design to that used in the 10-meter Keck telescopes, also sited at Mauna Kea. Using segments means that building the TMT won’t involve the many problems in constructing a giant mirror – not the least of which would have been transporting such a mirror to Hawaii and then up the mountain, which probably would have meant altering roads. Using segments also means that a broken mirror is an annoyance while a segment is replaced, rather than a catastrophe.

 

The segments are made of zero-expansion glass or glass ceramic. Each measures about 1.44 meters (56.6 inches) at the corners and they are 45 and 50 mm thick (about 2 inches), with a gap between each segment of only 2.5 mm (0.1 inch).

Each segment of the primary mirror is held in place by a support system that uses 27 thin flexures that spread the load and prevent the mirror segment distorting under its own weight. This support system can also compensate for temperature changes and shifts in weight as the mirror is tilted.









                           

TMT support structure

The secondary mirror that redirects the focused image from the primary mirror gives some idea of the scale of the telescope. The secondary is 3.1 meters (10 feet) in diameter, which is as large as the primary mirror on other telescopes.


 

Tertiary mirror assembly

 

There’s also an articulated tertiary mirror in the TMT. It’s job is to steer the light beam from the secondary mirror to any of eight scientific instruments installed in the telescope. The latticework structure of the TMT is supported in two Nasmyth platforms that also house the larger scientific instruments, so the tertiary mirror is necessary to bring these into play.



Only three instruments will be used when it first becomes operational. These include the Wide Field Optical Spectrometer (WFOS), the Infrared Imaging Spectrometer (IRIS) and the Infrared Multi-object Spectrometer (IRMS).



All these components work together as part of the Adaptive Optics (AO) system, which uses the ability of the telescope to reconfigure its elements to compensate for atmospheric turbulence in real time. This turbulence is what makes stars twinkle and it can ruin observations with even a moderate-sized telescope. The AO system, however, can stabilize the image to use the full power of the 30-meter mirror and give the TMT 144 times the light collecting area of the Hubble telescope and ten times better spatial resolution at near-infrared and longer wavelengths.


Covering the light spectrum from 310 nanometers in the ultraviolet to 28 microns in the infrared, the primary mirror has a focal length of f/15 (450 m/1,476 ft) and a focal ratio of f/1.

1948 Delahaye 135 M Figoni et Falaschi Cabriolet


1953 Alfa Romeo BAT 5 Concept Car


1964 Bizzarrini 5300 Corsa


1939 BMW 328


1954 Buick Wildcat II


1936 Delahaye 135 Competition Court Figoni et Falaschi Coupe


1938 Delahaye 135 M Figoni et Falaschi Cabriolet


1948 Delahaye 135 M Figoni et Falaschi Cabriolet Narval


1937 Delahaye 135 Figoni et Falaschi Torpedo Cabriolet


1949 Delahaye 175 S Saoutchik Roadster


1929 duPont Model G Speedster


1931 duPont Model H Merrimac Sport Phaeton


1921 Farman A6B Super Sport Torpedo


1953 Kurtis 500S Roadster


1938 Phantom Corsair


1938 Talbot Figoni Falaschi 7/23 Faux Cabriolet


1934 Voisin C15 Saloit Roadster

World‘s first smartphone for the blind, MADE IN INDIA

The world's first smartphone for blind people is here. Soon, they will be able to read SMSes and emails on this phone, which converts all text into Braille patterns. 

"We have created the world's first Braille smartphone," says its innovator, Sumit Dagar, whose company is being incubated at the Centre for Innovation Incubation and Entrepreneurship, located in IIM Ahmedabad campus. "This product is based on an innovative 'touch screen' which is capable of elevating and depressing the contents it receives to transform them into 'touchable' patterns," he says. 

Dagar, who is a post-graduate from the National Institute of Design (NID), says he was motivated to develop the device when he realised that so far, technology was only serving the mainstream and ignoring the marginalised. He is collaborating with IIT Delhi on making the prototype, which is currently being tested at L V Prasad Eye Institute in Hyderabad. 

"The response during the test has been immense. It comes out as a companion more than a phone to the user. We plan to do more advanced versions of the phone in the future," Dagar adds. 

Dagar started the project three years ago while studying interaction designing at NID. After working with a couple of companies, he gave up his job to concentrate on his technology, formed a team of six people and started his venture, Kriyate Design Solutions. Currently, the venture is being funded by Rolex Awards under its Young Laureates Programme, in which they select five people from across the world every two years and fund their projects. 

How it works 

The smartphone uses Shape Memory Alloy technology, based on the concept that metals remember their original shapes, i.e. expand and contract to its original shape after use. 

The phone's 'screen' has a grid of pins, which move up and down as per requirement. The grid has a Braille display, where pins come up to represent a character or letter. 

This screen will be capable of elevating and depressing the contents to form patterns in Braille. 

All other elements are like any other smartphone.

Georgia Aquarium: The Largest Aquarium in the World

The world’s largest aquarium is located in Atlanta, Georgia. It houses more than 120,000 animals, representing 500 species in 8.5 million gallons of water. There are 60 different habitats with 12,000 square feet of viewing windows, and it cost $290 million to build.

Georgia Aquarium was the result of the vision of one enterprising businessman Bernard Marcus, who dreamed of presenting Atlanta with an aquarium that would encourage both education and economic growth. Marcus was so inspired by aquariums that after visiting 56 of them in 13 countries with his wife, he donated $250 million toward what was to become Georgia Aquarium. Additional $40 million came in as corporate donations. The land was donated by the Coca Cola Company.

How to remote log out from Gmail, Facebook

 













If you headed home from office, without logging out of Facebook or Gmail, you can do so from anywhere using the 'remote log out' feature. 


In Facebook, click on the tiny gear sign on the top right of the page, go to 'account settings' and then to 'security' on the left pane. Under 'security settings', click on 'active sessions'.

No one else might be using your account, but you would not have logged out of Facebook, leaving the session active. Anyone can gain access to your account in such circumstances. To remote log out, click on 'end activity'.

In Gmail, at the bottom right side of the page, you will see details of your latest email access. If someone else is simultaneously using your account, you will see a notification there.

Click on the 'Details' link below it. A new window opens, with a notification on whether the account is simultaneously open elsewhere. Like in the case of FB, you might not have logged out of the account, leaving it active. If so, you will see an option to 'log out of all sessions'. It also shows you the details of your previous 10 accesses to the account.

Delete Your Google Account After Your Death

Not many of us like thinking about death — especially our own. But making plans for what happens after you’re gone is really important for the people you leave behind. So today, we’re launching a new feature that makes it easy to tell Google what you want done with your digital assets when you die or can no longer use your account.

The feature is called Inactive Account Manager — not a great name, we know — and you’ll find it on your Google Account settings page. You can tell us what to do with your Gmail messages and data from several other Google services if your account becomes inactive for any reason.



 


For example, you can choose to have your data deleted — after three, six, nine or 12 months of inactivity. Or you can select trusted contacts to receive data from some or all of the following services: +1s; Blogger; Contacts and Circles; Drive; Gmail; Google+ Profiles, Pages and Streams; Picasa Web Albums; Google Voice and YouTube. Before our systems take any action, we’ll first warn you by sending a text message to your cellphone and email to the secondary address you’ve provided.

World's Largest Solar-Powered Boat

The MS Tûranor PlanetSolar, the world's largest solar-powered boat. in the name of science. Equipped with unique instruments, the Tûranor will carry a team of scientists who will monitor the air and water of the Atlantic Ocean's Gulf Stream, a current which influences the climates of North America's east coast and Europe's west. The goal is to gain understanding of the processes which regulate climate.

Circling the North Atlantic

The Tûranor has set out from La Ciocat, France, on a four-month expedition that will encircle the North Atlantic. The vessel's instruments will undergo testing as the boat makes its way out of the Mediterranean. The hard graft, so far as the science is concerned, will not begin until it reaches Miami, Florida, at the south-western tip of the Gulf Stream.




Being powered solely by photovoltaics, the catamaran has no emissions which could otherwise influence sensitive instruments and the data they collect.

For science

A continuous series of physical and biological measurements will be taken in the water and air to study the key parameters of climate regulation, specifically atmospheric aerosols and phytoplankton.

India's largest shopping mall opens in Kerala

Billed as one of Asia’s biggest shopping malls, the Lulu Shopping Mall was opened to public on 10th March. Built at a cost of over Rs.1,0600 crore, the mall is spread over 2.5 million square feet of space and is owned by EMKE group of United Arab Emirates (UAE) businessman M.A. Yousuf Ali, who hails from Kerala. The mall has nine theatres, 16 pairs of escalators, elevators and travelators. There is a 3,500-seat multi-cuisine food court and parking for 3,000 cars.