Tuesday, October 27, 2009

Operation Ice Bridge will soon reach the end of its operational lifetime


A satellite launched by NASA in 2003 to keep an eye on the massive ice sheets that cover the Polar Regions will soon reach the end of its operational lifetime. A second satellite, dubbed ICESat-II, won’t launch until 2014 at the earliest.

That means a six-year gap for scientists who use the data collected by the satellite’s laser altimeter system to monitor such things as elevation changes in the ice. Researchers use that information to understand not only how the ice changes over time, but to help calculate the amount of sea level rise from ice lost to the ocean.But NASA has a backup plan to bridge the gap — the largest airborne survey of Earth’s polar ice ever flown.

Operation Ice Bridge is a six-year mission to fly an instrumented airplane out of Punta Arenas, Chile, across the ice and snow of West Antarctica and the Antarctic Peninsula. A modified DC-8 jetliner will crisscross ice shelves, sea ice, glaciers and the massive western ice sheet beginning this month.

Seelye Martin, chief scientist for the project from the University of Washington, said Ice Bridge is a partial replacement for ICESat, which stands for Ice, Cloud and Land Elevation Satellite. The DC-8 will carry precision instruments to map the ice topography just as ICESat did, allowing scientists to monitor elevation fluctuations in the ice sheet as well as changes in sea ice thickness.

Monday, October 19, 2009

SPACE SHUTTLE ATLANTIS - Summary


Atlantis' mission will focus on storing spare hardware on the exterior of the International Space Station. The 11-day flight will include three spacewalks and the installation of two platforms to the station’s truss, or backbone. The platforms will hold spare parts to sustain station operations after the shuttles are retired. This equipment is large and can only be transported using the unique capability of the shuttle. Atlantis also will bring back a station crew member after more than two months aboard the orbiting laboratory. This is slated to be the final space shuttle crew rotation flight for the station.
CREW:
Charlie Hobaugh (hoe-baw)
Barry E. Wilmore
Leland Melvin
Randy Bresnik
Mike Foreman
Robert “Bobby” Satcher
Nicole Stott
FACTS:

For MISSE-7 there are 700 materials samples that will be installed in holders and placed in two experiment trays, called Passive Experiment Containers 7A and 7B.
• The PECs will be mounted on the outside of the station.
• The experiments include tests of spacesuit materials for use on the lunar surface and materials for the solar arrays being designed for the Orion spacecraft.
• This installment of experiments for the MISSE program will be the first to receive power directly from the station and use its communication system to receive commands and downlink data.
• During STS-129, the two platforms that will be installed on the station are known as ExPRESS Logistics
Carriers 1 & 2. EXPRESS stands for “Expedite the Processing of Experiments to the Space Station.” Each
ELC can hold up to 9,800 pounds (total with spares, ELC 1: 13,842 lbs, ELC 2: 13,365 lbs). The ELCs hold:
• 2 spare gyroscopes that help maintain the station’s attitude in orbit
• 2 nitrogen tank assemblies used for pressurizing the station's ammonia cooling system
• 2 pump modules for pumping ammonia from a tank through cooling line in the truss
• an ammonia tank assembly. Ammonia is used to move excess heat from inside the station to the radiators located outside.
• a spare latching end effector, or hand, that allows the station's robotic arm to grapple
• a spare trailing umbilical system for the Mobile Transporter, the rail car that the arm travels on.
• a high-pressure gas tank for supplying oxygen for the airlock in support of spacewalks
• Two other ELCs will be delivered next year: one on STS-133 and one on STS-134.
• Shuttle Atlantis also will carry the Commercial Orbital Transportation Services Ultra High Frequency Communication Unit. It will be integrated on the station in preparation for Space Exploration Technologies’
(SpaceX) future flights to the orbiting laboratory.
• Developed by SpaceX, in collaboration with NASA, the unit will allow for communication between the station, SpaceX’s Dragon spacecraft, and ground-based mission control.
• STS-129 is the 2nd flight to carry two African-American astronauts. The first was STS-116, which included Robert Curbeam and Joan Higginbotham.

Monday, October 12, 2009

Antarctic meteorites help in the study of early solar system


Field researchers in Antarctica have returned with more than 17,500 meteorites over the 30-plus years that the extraterrestrial material has been collected from the frozen continent.

Yet meteorite science is still in its infancy, and the collected rocks still hold plenty of surprises that could shape our understanding of the solar system, according to scientists involved in the search and characterization of the Antarctic meteorite collection.

A paper in the journal Nature earlier this year illustrates his point. Scientists who analyzed two meteorites collected by Harvey’s team during the 2006-07 field seasons in an area called the Graves Nunatak ice field reported that the rocks are unlike anything found before. The composition of the light-colored rocks has similarities to the Earth’s crust, which has implications for how some asteroids form and evolve.

Additional work by scientists in the community may involve isotopic analysis to help “fingerprint” the sample to determine its origin. For example, scientists can identify rare Martian rocks by analyzing the nitrogen and noble gases found in glass pockets in the rocks created by impacts. That information is matched against the data collected by NASA’s Viking program about Mars’ atmosphere.

All those rocks, ranging in size from smaller than a marble to larger than a football, are bagged and boxed in Antarctica in their frozen state for shipment back to the United States.Additional work by scientists in the community may involve isotopic analysis to help “fingerprint” the sample to determine its origin. For example, scientists can identify rare Martian rocks by analyzing the nitrogen and noble gases found in glass pockets in the rocks created by impacts. That information is matched against the data collected by NASA’s Viking program about Mars’ atmosphere.

Thursday, September 10, 2009

Astronomers on Centaurus galaxy

Astronomers said that Centaurus A a new found galaxy emits a radio glow covering an area about 200 times bigger than the full moon.

With the radio wave information, a team has formed the image of the galaxy which lies some 14 million light-years away, in the constellation and has a black hole that is 50 million times the mass of the Sun. This image will help the astronomers to understand about the evolution of galaxy and about black holes.

On this information Centaurus A is so big and bright galaxy and that no one would have ever tried making such an image.

The astronomers used CSIRO's Australia Compact Array telescope near Narrabri, NSW, to view the galaxy for more than 1200 hours, over several years and got 406 individual images, which were mosaic together to make one large image.

Centaurus A is the nearby of the galaxies with a big black hole producing radio glow, which makes it the easiest to study.

Thursday, September 03, 2009

Safe way to decrease weight

Weight cycling, or losing and regaining weight repeatedly, may increase the risk of developing gallstones.

You can take several measures to decrease the risk of developing gallstones during weight loss. Losing weight gradually, instead of losing a large amount of weight quickly, lowers your risk. Depending on your starting weight, experts recommend losing weight at the rate of 1/2 to 2 pounds per week. Losing weight at this rate commonly occurs for up to 6 months. After 6 months, weight loss usually declines and weight stabilizes because individuals in lower weight groups use fewer calories (energy). You can also decrease the risk of gallstones associated with weight cycling by aiming for a modest weight loss that you can maintain. Even a loss of 5 to 10 percent of body weight over a period of 6 months or more can improve the health of an adult who is overweight or obese.

Your food choices can also affect your gallstone risk. Experts recommend including some fat in your diet to stimulate gallbladder contracting and emptying. Current recommendations indicate that 20 to 35 percent of your total calories should come from fat. Studies have also shown that diets high in fiber and calcium may reduce the risk of gallstone development.
Finally, regular physical activity is related to a lower risk for gallstones. Aim for approximately 60 minutes of moderate- to vigorous-intensity activity on most days of the week to manage your body weight and prevent unhealthy weight gain. To sustain weight loss, engage in at least 60 to 90 minutes of daily moderate-intensity physical activity.

Monday, August 31, 2009

Symptoms of stomach cancer

In most cases symptoms of stomach cancer are not easy to find out. As the cancer grows to a stage, the most common symptoms are:
uneasiness in the stomach area
Feeling full or overstuffed after a small meal
sickness and vomiting
Weight loss

Studies have found the following risk factors for stomach cancer:

Age: Most people with this disease are 72 or older.

Sex: Men are more likely than women to develop stomach cancer.

Race: Stomach cancer is more common in Asian, Pacific Islander, Hispanic, and African Americans than in non-Hispanic white Americans.

Diet: Studies suggest that people who eat a diet high in foods that are smoked, salted, or pickled may be at increased risk for stomach cancer. On the other hand, eating fresh fruits and vegetables may protect against this disease.

Helicobacter pylori infection: H. pylori is a type of bacteria that commonly lives in the stomach. H. pylori infection increases the risk of stomach inflammation and stomach ulcers. It also increases the risk of stomach cancer, but only a small number of infected people develop stomach cancer.

Friday, August 28, 2009

Body mass index

Various methods are used to determine if someone’s weight has increased his or her health risks. Some are based on the relationship between height and weight; others are based on measurements of body fat. The most commonly used method today is the body mass index (BMI). BMI is an index of weight adjusted for the height of an individual.

BMI can be used to screen for both overweight and obesity in adults. It is the measurement of choice for many obesity researchers and other health professionals, as well as the definition used in most published information on overweight and obesity. BMI is a calculation based on height and weight, and it is not gender-specific in adults. BMI does not directly measure percentage of body fat, but it is a more accurate indicator of overweight and obesity than relying on weight alone.BMI is calculated by dividing a person’s weight in kilograms by height in meters squared. The mathematical formula is “weight (kg)/height (m²).”