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Messages - Md. Limon Hossain

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16
NASA Launches Most Capable and Robust Rover to Explore Mars
 
 
CAPE CANAVERAL, Fla. -- NASA began a historic voyage to Mars with the Nov. 26 launch of the Mars Science Laboratory (MSL), which carries a car-sized rover named Curiosity. Liftoff from Cape Canaveral Air Force Station aboard an Atlas V rocket occurred at 10:02 a.m. EST.

"We are very excited about sending the world's most advanced scientific laboratory to Mars," NASA Administrator Charles Bolden said. "MSL will tell us critical things we need to know about Mars, and while it advances science, we'll be working on the capabilities for a human mission to the Red Planet and to other destinations where we've never been."

The mission will pioneer precision landing technology and a sky-crane touchdown to place Curiosity near the foot of a mountain inside Gale Crater on Aug. 6, 2012. During a nearly two-year prime mission after landing, the rover will investigate whether the region has ever offered conditions favorable for microbial life, including the chemical ingredients for life.

"The launch vehicle has given us a great injection into our trajectory, and we're on our way to Mars," said MSL Project Manager Peter Theisinger of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "The spacecraft is in communication, thermally stable and power positive."

The Atlas V initially lofted the spacecraft into Earth orbit and then, with a second burst from the vehicle's upper stage, pushed it out of Earth orbit into a 352-million-mile (567-million-kilometer) journey to Mars.

"Our first trajectory correction maneuver will be in about two weeks," Theisinger said. "We'll do instrument checkouts in the next several weeks and continue with thorough preparations for the landing on Mars and operations on the surface."

Curiosity's ambitious science goals are among the mission's many differences from earlier Mars rovers. It will use a drill and scoop at the end of its robotic arm to gather soil and powdered samples of rock interiors, then sieve and parcel out these samples into analytical laboratory instruments inside the rover. Curiosity carries 10 science instruments with a total mass 15 times as large as the science-instrument payloads on the Mars rovers Spirit and Opportunity. Some of the tools are the first of their kind on Mars, such as a laser-firing instrument for checking rocks' elemental composition from a distance, and an X-ray diffraction instrument for definitive identification of minerals in powdered samples.

To haul and wield its science payload, Curiosity is twice as long and five times as heavy as Spirit or Opportunity. Because of its one-ton mass, Curiosity is too heavy to employ airbags to cushion its landing as previous Mars rovers could. Part of the MSL spacecraft is a rocket-powered descent stage that will lower the rover on tethers as the rocket engines control the speed of descent.

The mission's landing site offers Curiosity access for driving to layers of the mountain inside Gale Crater. Observations from orbit have identified clay and sulfate minerals in the lower layers, indicating a wet history.

Precision landing maneuvers as the spacecraft flies through the Martian atmosphere before opening its parachute make Gale a safe target for the first time. This innovation shrinks the target area to less than one-fourth the size of earlier Mars landing targets. Without it, rough terrain at the edges of Curiosity's target would make the site unacceptably hazardous.

The innovations for landing a heavier spacecraft with greater precision are steps in technology development for human Mars missions. In addition, Curiosity carries an instrument for monitoring the natural radiation environment on Mars, important information for designing human Mars missions that protect astronauts' health.

The mission is managed by JPL for NASA's Science Mission Directorate in Washington. The rover was designed, developed and assembled at JPL. NASA's Launch Services Program at the Kennedy Space Center in Florida managed the launch. NASA's Space Network provided space communication services for the launch vehicle. NASA's Deep Space Network will provide spacecraft acquisition and mission communication.

For more information about the mission, visit:

http://www.nasa.gov/msl


For more information about the Deep Space Network, visit:

http://deepspace.jpl.nasa.gov/dsn


Source: NASA Website

17
BBA Discussion Forum / Re: Finance
« on: November 26, 2011, 10:39:52 PM »
Our share market has been destroyed for corruption, bad policies, mismanagement, lack of skills and for politics. So be careful while you going to invest. In this situation share market is the best place for bad investment.

18
Science Discussion Forum / Re: Energy from the Sun
« on: November 22, 2011, 05:13:24 PM »

What is solar power……..?

Solar power is derived from energy from the sun. There are two main types of technologies for converting solar energy to electricity: photovoltaic (PV) and solar-thermal electric. Photovoltaic conversion produces electricity directly from sunlight in a photovoltaic (solar) cell. Solar-thermal electric generators concentrate solar energy to heat a fluid and produce steam to drive turbines.

Advantages of Solar Power:

   The power source of the sun is absolutely free.
 
   The production of solar energy produces no pollution.
 
   The technological advancements in solar energy systems have made them extremely cost effective.
 
   Most systems do not require any maintenance during their lifetime, which means you never have to put money into them.
 
   Unlike traditional monstrous panel systems, many modern systems are sleeker such as Uni-Solar rolls that lay directly on   the roof like regular roofing materials.
 
   Solar energy can dramatically reduce the electric bills.
 
   Solar energy systems are now designed for particular needs. For instance, you can convert your outdoor lighting to solar.

19
Science Discussion Forum / Re: Energy from the Sun
« on: November 22, 2011, 05:01:58 PM »
Dear Md. Faruque Hossain: I can not understand your comment.........!!

"The solar power can not run without the energy that we taken from the sun. Sun is the most powerful elements that created the energy and power that we use in different sectors."

20
Science Discussion Forum / Energy from the Sun
« on: November 21, 2011, 09:01:39 PM »
Energy from the Sun
The sun has produced energy for billions of years.  Solar energy is the sun’s rays (solar radiation) that reach the Earth. This energy can be converted into other forms of energy, such as heat and electricity.


Radiant energy from the sun has powered life on Earth for many millions of years

In the 1830s, the British astronomer John Herschel famously used a solar thermal collector box (a device that absorbs sunlight to collect heat) to cook food during an expedition to Africa. Today, people use the sun's energy for lots of things.

Solar Energy Can Be Used for Heat and Electricity


When converted to thermal (or heat) energy, solar energy can be used to:

•   Heat water — for use in homes, buildings, or swimming pools
•   Heat spaces — inside homes, greenhouses, and other buildings
•   Heat fluids — to high temperatures to operate a turbine to generate electricity

Solar energy can be converted to electricity in two ways:


•   Photovoltaic (PV devices) or “solar cells”
change sunlight directly into electricity. Individual PV cells are grouped into panels and arrays of panels that can be used in a wide range of applications ranging from single small cells that charge calculator and watch batteries, to systems that power single homes, to large power plants covering many acres.

•   Solar Thermal/Electric Power Plants
generate electricity by concentrating solar energy to heat a fluid and produce steam that is used to power a generator. In 2009, there were 13 solar thermal-power generating units operating in the United States, 11 in California, 1 in Arizona, and 1 in Nevada.

The main benefits of solar energy are:


•   Solar energy systems do not produce air pollutants or carbon-dioxide
•   When located on buildings, they have minimal impact on the environment

Two limitations of solar energy are:

•   The amount of sunlight that arrives at the Earth's surface is not constant. It varies depending on location, time of day, time of year, and weather conditions.
•   Because the sun doesn't deliver that much energy to any one place at any one time, a large surface area is required to collect the energy at a useful rate.


Source: http://www.eia.gov/energyexplained/index.cfm?page=solar_home

21
Heritage/Culture / The National Anthem Of Bangladesh - Amar Sonar Bangla
« on: November 15, 2011, 05:38:21 PM »
The National Anthem Of Bangladesh - Amar Sonar Bangla

আমার সোনার বাংলা
আমি তোমায় ভালোবাসি।
চিরদিন তোমার আকাশ, তোমার বাতাস
আমার প্রাণে বাজায় বাঁশি।

ও মা, ফাগুনে তোর আমের বনে
ঘ্রাণে পাগল করে--
(মরি হায়, হায় রে)
ও মা, অঘ্রাণে তোর ভরা খেতে,
(আমি) কি দেখেছি মধুর হাসি।।

কী শোভা, কী ছায়া গো,
কী স্নেহ, কী মায়া গো--
কী আঁচল বিছায়েছ
বটের মূলে, নদীর কূলে কূলে।।

মা তোর মুখের বাণী
আমার কানে লাগে
সুধার মতো--
(মরি হায়, হায় রে)
মা, তোর বদনখানি মলিন হলে
আমি নয়ন জলে ভাসি।।

22
Departments / Re: Bank Loan vs Indian
« on: November 15, 2011, 05:08:11 PM »
Yes Mr. nfeoffice; this is one of the good example of professionalism.

23
BBA Discussion Forum / Re: Share Market News
« on: November 14, 2011, 09:21:05 PM »
Share market is one of the major key of our economy. Million’s of people are involved in the share market. Without the share markets the economy can not be accelerate as needed pace. If our economy can not improve then we are students will be jobless. Our hard work and investment on our education will be meaning less.

Dear Kibria: You have share lots of news about share markets from last couple of months. That’s why I start with you. What are the major problems are existing in our share markets?

24
BBA Discussion Forum / Re: Share Market News
« on: November 13, 2011, 10:51:16 PM »
Dear Kibria: We are getting lots of information about our share markets through different media. Now we should analyze the markets. No doubt that our country share markets has been collapsed. Now we have to discuss how the market can be reform as a strong or at least semi-strong market.


We should find out the problems and then possible ways & alternatives. And then possible ways and alternatives should be transforming into action.


25
Use of Forum / Re: dekar kew nai
« on: November 13, 2011, 10:29:32 PM »
Dear All: The all user of DIU forum are jewel. Better than any kinds of hero. Just stay with your beloved university forum. Time will tell you that who are you……….?

26
Be a Business man/woman / Re: Professionalism in the Workplace
« on: November 13, 2011, 09:57:40 PM »
Thank you very much sir for your post. “Professionalism in the Workplace” is helping me to clarify my self concept. Its help me to find out what I really I am….!! How I see myself….!! How I think other see me…..!! And most important thing is how I would like to be…!!

27
Pharmacy / Re: মূল্যবান ভেষজ আমলকী
« on: November 13, 2011, 07:17:47 AM »
Wonderful history about Amloki tree...................and information.

Thank you Mr. Asif Hossain for the history and information.

28
Interesting information............Keep-it-up>>>>>>>>>>>>>>>>>>>

29
BBA Discussion Forum / ঈদ মুবারক...
« on: November 07, 2011, 06:59:12 AM »
ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক... ঈদ মুবারক...



30
Pharmacy / Re: Pain killer……!!
« on: November 01, 2011, 07:47:33 AM »
Dear Arif:
Thank You very much for your information. A new way you revealed. But what is CNS side effects....?

I am looking forward for your answer.

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