Wednesday, December 17, 2014

Mars

Mars, Viking Orbiter Mosaic JB1960
The center of Mars is at latitude 30 degrees north, longitude 270 degrees. NASA's Viking Mission to Mars was composed of two spacecraft, Viking 1 and Viking 2, each consisting of an orbiter and a lander. The primary mission objectives were to obtain high resolution images of the Martian surface, characterize the structure and composition of the atmosphere and surface, and search for evidence of life. The results from the Viking experiments give our most complete view of Mars to date. Volcanoes, lava plains, immense canyons, cratered areas, wind-formed features, and evidence of surface water are apparent in the Orbiter images. The planet appears to be divisible into two main regions, northern low plains and southern cratered highlands. Superimposed on these regions are the Tharsis and Elysium bulges, which are high-standing volcanic areas, and Valles Marineris, a system of giant canyons near the equator. The surface material at both landing sites can best be characterized as iron-rich clay. Measured temperatures at the landing sites ranged from 150 to 250 K, with a variation over a given day of 35 to 50 K. Seasonal dust storms, pressure changes, and transport of atmospheric gases between the polar caps were observed. The biology experiment produced no evidence of life at either landing site. June 1998.

View more images of Mars at ScienceSource.com

NASA Curiosity Rover Detects Methane on Mars

Curiosity rover, artwork - SS5365
Since landing on the red planet in 2012, the Mars Curiosity Rover has been has been analyzing the planet's atmosphere and measuring its chemical components.  Curiosity has recently detected concentrated spikes of methane, a gas normally released by microbial organisms here on Earth, which may indicate the presence of life on Mars.  Scientists have yet to identify the source of the methane gas, which may be trapped in ice on the planet's surface or released from underground fissures due to mechanical or thermal stress.  Most of the Martian atmosphere consists of carbon dioxide, with methane measuring about 0.7 parts per billion by volume (ppbv).  By comparison, Earth's atmosphere contains about 1,800 (ppbv) of methane.

Thursday, December 11, 2014

New Drug Combines Hormones to Treat Obesity and Diabetes

Research on obesity - BC4625
Researchers from the Hemholtz Diabetes Center in Munich, Germany were able to successfully test a drug on rodents which reversed the effects of obesity and diabetes over the course of three weeks.  At the end of the study, the fat mass of the rodents dropped by a third and their blood glucose fell by half.  The drug is a combination of the hormones glucagon-like peptide (GLP-1), gastric inhibitory peptide (GIP) and glucagon, which are responsible for regulating blood sugar and appetite.  The newly created hybird-hormone would be able to stimulate chemical signals to trigger the body's metabolism to lower blood glucose, burn fat, and lose weight. 

Bariatric surgery is typically reserved for patients suffering from life threatening obesity, and sometimes involves removing part of the stomach or small intestine to limit food intake.  Recent studies have shown that these procedures can alter the way hormones are released from the gut in order to stimulate weight loss.  This latest finding may be the first step in creating a drug with the benefits of weight loss surgery, without the risks associated with the operation.

Friday, December 5, 2014

NASA Launches Orion Deep Space Capsule

Orion crew exploration vehicle, artwork - SM9377
NASA is testing an unmanned version of a newly developed crew capsule to be used in conjunction with a more powerful rocket that will debut in the next few years.  The technology currently in development would be designed to send astronauts past the International Space Station to other planetary bodies such as the Moon and Mars.  The Orion capsule launch is the first step in testing the vehicle's heat shielding and re-entry parachutes, as it withstands temperatures of around 3,600°F while traveling almost 20,000mph.

View more images of the "Orion Deep Space Capsule"

Wednesday, December 3, 2014

HIV Evolving into Less Virulent Form


HIV Human Cells - FC0359
Researchers from Oxford University conducted a recent study of HIV infected patients from Botswana and South Africa which indicated that the virus may be evolving as it adapts to our body's immune system and antiretroviral therapies.  As the virus continues to try and evade the immune system, it reduces its own ability to replicate and spread throughout the body.  As a result, it may take much longer for HIV infected individuals to develop AIDS as weaker mutated versions of the virus circulate in the body.  However, researchers reiterate that HIV is far from becoming harmless but are cautiously optimistic that antiretroviral therapy against weaker evolutions of the virus can eventually lead to better control of the epidemic.

It's estimated that over 35 million people are infected with HIV, which attacks the immune system and leaves the body more susceptible to common infections, eventually progressing into AIDS.