An Atlas V rocket carrying Landsat 8 seen just after launch at Vandenberg Air Force Base, Calif. (NASA)

NASA’s latest Earth-observing satellite rocketed into space today continuing a program which began more than 40 years ago.

An Atlas V rocket carrying the Landsat Data Continuity Mission (LDCM) spacecraft launched from Vandenberg Air Force Base in Lompoc, California.

NASA officials called today’s launch “picture perfect.”   The spacecraft is now on its own after a successful separation from the Centaur upper stage.

The LDCM is the eighth in a series of global observational spacecraft called Landsat, a collaborative effort between NASA and the U.S. Geological Survey (USGS).

According to NASA, it will play a critical role in monitoring, understanding and managing the resources, such as food and water, needed to sustain human life.

After three months of testing in orbit, the satellite will become known as Landsat 8, and all operational control of the spacecraft will transfer to USGS.

All Landsat data and imaging will continue to be collected by USGS primary ground stations in South Dakota and Australia.

Orbiting Earth every 99 minutes, Landsat 8 will be able to image Earth every 16 days as it circles the globe in a near polar orbit. Two new sophisticated instruments, Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS), will allow Landsat 8 to provide image and data information that wasn’t possible with previous Landsat satellites.

Landsat 7 took these images showing the significant shrinkage of central Asia’s Aral Sea from 1977 to 2010 due to water diversion for agricultural use. (USGS)

The OLI will cover wide areas of the Earth’s surface, sending back data and high definition images to help observers distinguish between various surfaces; such as urban, agricultural and forested areas.

The TIRS will use new technology which applies quantum physics to measure land surface temperature in two thermal bands, helping observers differentiate the temperature of the Earth’s surface from that of the atmosphere.

The Landsat mission to study and monitor our planet’s land masses began with the launch of Landsat 1  in 1972.

Since then, Landsat 2, 3, 4, 5 and 7 have all been put into service.  Landsat satellites 1 through 4 were taken out of service from the late 1970s through the early 1990s.

Landsat 5 , launched in 1984, was recently taken out of service and Landsat 6 never made it into orbit after a fuel line exploded seven minutes after liftoff.  Along with the just-launched Landsat 8, Landsat 7, which was sent into orbit in 1999, is the only remaining Landsat observing satellite still in service.

Landsat satellites snapped these Washington state images of  Mount St. Helens, which was surrounded by forests in 1974. Three months after the 1980 volcanic eruption, devastation caused by the blast is evident. By 2011, much of the damaged region had started to regrow. (USGS)

The imaging and data provided by the Landsat spacecraft  have helped scientists  better understand our planet’s climate, carbon cycle, ecosystems, water cycle, biogeochemistry and changes to Earth’s surface, as well as our understanding of visible effects  human have made to land surfaces.

NASA and USGS say the information provided by Landsat over the last 40 years has helped improve human and biodiversity health, energy and water management, urban planning, disaster recovery, and agriculture, which in turn has helped develop the world economy.

NASA video overview of the LDCM Mission

Drawing of the path of near-Earth asteroid 2012ge DA14 when it passes close to Earth on Feb. 15, 2013. (NASA)

Earth is about to have a close encounter with an asteroid, the nearest an object of its size has ever come to our planet.

The fly-by is expected to occur at around 1924 UTC on Feb. 15, according to scientists at NASA’s Jet Propulsion Laboratory.

The US space agency says there’s no chance the asteroid will collide with Earth.

“This is a record-setting close approach,” says Don Yeomans of NASA’s Near Earth Object Program at JPL. “Since regular sky surveys began in the 1990s, we’ve never seen an object this big get so close to Earth.”

Scientists expect the asteroid to pass us at a distance of about 27,700 km from the surface of the Earth. That’s close enough for it to pass inside the ring of a number of geosynchronous weather and communications satellites currently orbiting the Earth at about 36,000 km from Earth’s surface above the equator.

However, the asteroid should fly well above most of the satellites and spacecraft circling the planet, including the International Space Station (ISS).

To get an idea of just how close the 2012 DA14 asteroid will get to us, consider that it will come nearer to us than the moon, about 1/13th of the distance to the Moon, which is 384,400 km from Earth.

It’s expected to whiz by our planet quite fast, at a speed of about 7.8 kilometers per second in a south-to-north direction. This will be the closest an asteroid has come to Earth in at least 30 years and will give researchers a unique opportunity  to study it.

The 2012 DA14 is quite small, weighing about 130,000 metric tons and measuring about 45 meters across, less than the width of a soccer field. Astronomers believe it is made of stone, rather than metal or ice.

The asteroid was discovered by astronomers at the OAM Observatory in La Sagra, Spain less than a year ago, on Feb. 23, 2012, which is why “2012″ is part of its name.

NASA video feature of asteroid fly-by

A few other asteroids have flown even closer to Earth, but they were much smaller than the one expected to zoom by this month.  Scientists say objects of this size fly this close to the Earth about once every 40 years; an actual collision with Earth happens about every 1,200 years.

The 2012 DA14 asteroid is so tiny, it’s expected to look like a small point of light, even to those using the biggest optical telescopes. Difficult to see with the naked eye, it will be easily visible with a good set of binoculars or a small telescope.

Astronomers say the best place to see the asteroid will be in Indonesia, but people in Eastern Europe, Asia and Australia should also be able to get a glimpse.

The public can watch the event through live feeds from telescopes in La Sagra and Tenerife, Spain.

NASA astronomers at the Goldstone Deep Space Communications Complex (GDSCC) in California’s Mojave Desert will use radar imaging to determine the orbit of the asteroid, allowing them to better predict future encounters. The imaging data will also be used to create a 3D map showing the asteroid from all sides and should reveal more about the asteroid’s physical characteristics, such as its size and spin.

Georgia Tech researchers found many types of bacteria, include E.coli, in the middle to upper regions of the troposphere. (Photo: USDA)

Scientists have discovered a considerable number of living microorganisms, including bacteria, in the middle to upper regions of the troposphere, the region of our atmosphere that’s about seven to 20 kilometers above the Earth’s surface.

Researchers from the Georgia Institute of Technology said their findings might help other scientists learn more about the role microorganisms play in forming ice that may impact weather and climate.

Health and medical experts studying the transmission of disease could also benefit by gaining new insight into long-distance transport of bacteria.

Conditions in the troposphere cannot support most other forms of life without the aid of special equipment. Temperatures there can drop to as low as -55° C and the air pressure and density are considerably lower than on earth.

Microorganisms, such as bacteria, are plentiful and can be found everywhere on the Earth and in the sea.

These hardy little forms of life not only survive but actually thrive in some of the harshest conditions known to man. They live within other forms of life, such as the human body; in the soil and the air surrounding us; in scalding hot springs; the great depths of the ocean; and inside rocks deep within the Earth’s crust.

A view outside the window of a DC-8 aircraft as air samples are gathered for a NASA study. Georgia Tech scientists found living microorganisms in the samples. (Photo: NASA)

The microorganisms  documented by Georgia Tech scientists were gathered from air samples recovered as part of NASA’s 2010 Genesis and Rapid Intensification Processes (GRIP) program, which studies low- and high-altitude air masses associated with tropical storms.

NASA gathered the air samples from aboard a DC-8 aircraft that flew over both land and ocean, including the Caribbean Sea and portions of the Atlantic Ocean during and after two major tropical hurricanes in 2010, Earl and Karl.

Attaching a special filter system developed by the Georgia Tech team to the aircraft’s outside air sampling probes, researchers were able to collect numerous particles, including the microorganisms.

Once the air samples were taken, the filters were removed from the aircraft and sent to researchers for examination.

Rather than resorting to conventional cell-culture techniques to make their analysis, the researchers instead used genomic techniques, including polymerase chain reaction (PCR) – a biochemical technology used in molecular biology that magnifies a piece of DNA, allowing scientists to generate millions of copies of the DNA sequence, as well as gene sequencing to spot and estimate the quantities of microorganisms contained within the air samples.

The researchers found more bacteria than fungi among the microorganisms.

“We did not expect to find so many microorganisms in the troposphere, which is considered a difficult environment for life,” said one of the study’s authors, Kostas Konstantinidis, an assistant professor at Georgia Tech. “There seems to be quite a diversity of species, but not all bacteria make it into the upper troposphere.”

Terry Lathem, a graduate student in Georgia Tech’s School of Earth and Atmospheric Sciences, aboard a NASA DC-8 aircraft while gathering samples of microorganisms in the atmosphere. (NASA)

The living bacterial cells found made up about 20 percent of the total particles detected within the size range of 0.25 to 1 microns in diameter.

Air samples taken over the ocean were found to contain mostly marine bacteria, while primarily terrestrial bacteria was found in samples taken above land.

The researchers also found that hurricanes had a major impact on the distribution and dynamics of microorganism populations.

Kostas Konstantinidis joins us for this weekend’s radio edition of Science World.  He’ll tell us how these findings could help advance research in climatology and medicine.

Check out the right column for scheduled air-times or listen now to the interview below.

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One out of every six stars in our Milky Way galaxy has an Earth-like planet orbiting it, according to two new studies. (Photo: Steve Jurvetson via Wikimedia Commons)

There are at least 17 billion Earth-sized worlds in our Milky Way galaxy, according to two new studies.

Both groups of scientists used data from NASA’s Kepler mission to reach their conclusions, which were presented to the American Astronomical Society in Long Beach, California.

The scientists found that the closer the planets are to their stars, the easier they are to find because they transit more frequently, giving scientists more opportunities to observe them.

One group, led by Francois Fressin of the Harvard-Smithsonian Center for Astrophysics (CfA), said its studies show 50 percent of stars in our galaxy have a planet the size of Earth or larger closely orbiting them.

Add in larger planets, which have been found to be in wider orbits around its star, and the percentage of stars with planets goes up to 70 percent, according to the researchers.

Based on current ongoing observations from the Kepler mission, along with others using different detection techniques, it looks like practically all Sun-like stars have planets, according to the Harvard-Smithsonian team.

A second group of researchers, from the University of California, Berkeley and the University of Hawaii at Manoa, found smaller exoplanets to be much more plentiful than larger ones in the star systems it observed. The analysis also confirmed that the frequency of planets increased as its size decreased, which team member Andrew Howard and the Kepler team reported last year.

Perhaps one percent of stars have planets the size of Jupiter, while 10 percent have planets the size of Neptune, according to the Berkeley/ Hawaii team. The group’s research also shows the exoplanets they observed, which were two or three times the diameter of Earth, are typically more like our solar system’s Uranus and Neptune, each of which has a rocky core  surrounded by helium and hydrogen gases and, perhaps, water.

Artist’s conception of the wide variety of planets detected by NASA’s Kepler spacecraft. (C. Pulliam & D. Aguilar/CfA)

They suggest planets orbiting close to their stars may even be water worlds, with oceans hundreds of kilometers deep, surrounding a rocky core.

Although the planets between one to two times larger than Earth may not necessarily be habitable,  the Berkeley/Hawaii team  said those planets might be rocky and, if they’re located within what they call the “Goldilocks zone” –not too hot, not too cold, just right for liquid water– could support life.

The Harvard-Smithsonian researchers found that, except for the gas giants, the type of star didn’t really have much effect on the size of its planets, contradicting previous findings. Neptune-type planets, they said, can be found just as frequently orbiting around relatively cool stars, called red dwarfs, as they are around sun-like stars. The same is true for smaller worlds.

“Earths and super-Earths aren’t picky,” said Guillermo Torres of the Harvard-Smithsonian team. “We’re finding them in all kinds of neighborhoods.”

As more data is gathered, more planets in larger orbits will be revealed, according to the Harvard-Smithsonian researchers. They say when Kepler’s mission is extended, astronomers should be able to spot Earth-sized planets at greater distances, including those with Earth-like orbits within the habitable zone.

The Martian meteorite known as “Black Beauty” weighs approximately 320 grams. (Carl Agee/University of New Mexico)

Scientists have determined a meteorite discovered in the Sahara Desert in 2011 is about 2.1 billion years old and could be the first meteorite to come from the surface of Mars.

The meteorite, designated NWA (North West Africa) 7034 and nicknamed “Black Beauty,” weighs about 320 grams and is loaded with Martian water. It is so uniquely different from other Martian meteorites that scientists say it is in a class of its own.

They believe Black Beauty, which contains 10 times more water than other Martian meteorites from unknown origins, formed during the beginning of the most recent geologic period on Mars, known as the Amazonian.

“The age of NWA 7034 is important because it is significantly older than most other Martian meteorites,” said Mitch Schulte, program scientist for the Mars Exploration Program at NASA headquarters in Washington. “We now have insight into a piece of Mars’ history at a critical time in its evolution.”

The NASA-funded team of scientists from various universities and institutions analyzed the mineral and chemical composition, age, and water content of the meteorite.

Black Beauty’s chemical composition includes organic carbon, which is similar to other Martian meteorites, known as SNC meteorites. However, other aspects of Black Beauty’s composition are very different.

“The texture of the NWA meteorite is not like any of the SNC meteorites,” said Andrew Steele, who led the carbon analysis at the Carnegie Institution’s Geophysical Laboratory. “This is an exciting measurement in Mars and planetary science. We now have more context than ever before to understanding where they may come from.”

Black Beauty, according to the research team, is made of cemented fragments of basalt, rock  formed from rapidly-cooled lava. The fragments are primarily feldspar and pyroxene, most likely from volcanic activity.

Scientists say the Black Beauty meteorite came from the surface, or crust, of Mars (NASA)

“This Martian meteorite has everything in its composition that you’d want in order to further our understanding of the Red Planet,” said Carl Agee, leader of the analysis team and director and curator at the University of New Mexico’s Institute of Meteoritics in Albuquerque. “This unique meteorite tells us what volcanism was like on Mars two billion years ago. It also gives us a glimpse of ancient surface and environmental conditions on Mars that no other meteorite has ever offered.”

Up until now,  SNC meteorites have been the only meteorite samples from the Red Planet  scientists have been able to study, however, their exact point of origin on Mars isn’t  known.  Scientists say recent data from NASA Mars lander and orbiter missions indicate the SNC meteorites are actually a mismatch with the Martian crust.

But Black Beauty does match up with surface rocks and outcrops studied by NASA’s Mars rovers, such as Curiosity, Opportunity and Spirit, as well as its orbiting satellites, like the Mars Odyssey Orbiter.

“The contents of this meteorite may challenge many long-held notions about Martian geology,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “These findings also present an important reference frame for the Curiosity rover as it searches for reduced organics in the minerals exposed in the bedrock of Gale Crater.”

Artist’s rendition of astronauts on Mars. (NASA)

Traveling into deep space could accelerate the onset of Alzheimer’s disease, an incurable form of dementia, according to a new report.

The NASA-funded study assessed how cosmic radiation would impact the astronauts throughout their trip in deep space. The effect of cosmic radiation on the human body has been a  concern for the US space agency as it plans manned missions into deep space, such as one to a distant asteroid in 2021, and another to Mars in 2035.

Earth’s magnetic field usually keeps us, and those in low Earth orbit, safe from the perils of cosmic radiation. However, beyond Earth’s protective magnetic fields, space travelers are exposed to a constant barrage of radiation.

With adequate warning, such as in the case of solar flares, steps can be taken to protect astronauts from dangerous forms of radiation. However, other forms of cosmic radiation, which occur without warning, cannot be blocked as effectively.

“Galactic cosmic radiation poses a significant threat to future astronauts,” said M. Kerry O’Banion,  a professor in the University of Rochester Medical Center (URMC) and senior author of the study. “The possibility that radiation exposure in space may give rise to health problems such as cancer has long been recognized. However, this study shows for the first time that exposure to radiation levels equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer’s disease.”

Artist’s illustration of the shape and function of the Earth’s magnetic field that protects us from harmful cosmic radiation (NASA)

In the past,  scientists studied the impact of cosmic radiation on a living being’s cardiovascular and musculoskeletal systems, as well as potential risks of contracting various forms of cancer.But the new study,  published in  PLOS ONE, examined the possible effects of space radiation on neurodegeneration, a gradual loss of brain structure or function.

For this study, researchers wanted to find out what role, if any, cosmic radiation plays in accelerating the biological and cognitive indicators of Alzheimer’s disease, especially in those  predisposed to developing the illness.

They specifically wanted to learn more about the impact of radiation from high-mass, high-charged (HZE) particles, which come in many forms and travel through space with the force of exploding stars.

Instead of examining hydrogen protons, which are produced by solar flares, the researchers decided to study iron particles. They say HZE particles, such as iron, when combined with their high rate of speed, are able to go through solid objects, like a spacecraft’s walls and protective shielding.

“Because iron particles pack a bigger wallop, it is extremely difficult, from an engineering perspective, to effectively shield against them,” said O’Banion. “One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.”

Brain affected by Alzheimer’s Disease (left) vs normal brain (right) – (US Dept of Veterans Affairs)

The researchers exposed mice to various doses of radiation, including levels that would be similar to what astronauts would experience during deep space voyages.To evaluate the cognitive and biological impact of the radiation exposure, the mice were then put through a series of experiments in which they had to recall objects or specific locations. Researchers observed that the radiation- exposed mice were much more likely to fail these tests, suggesting neurological impairment, earlier than the symptoms would typically appear.

Along with symptoms of neurological damage, the researchers found that the mice’s brains also showed signs of vascular changes and had a greater than usual buildup of beta amyloid, the protein “plaque” that gathers in the brain and is one of the characteristics of Alzheimer’s Disease.

“These findings clearly suggest that exposure to radiation in space has the potential to accelerate the development of Alzheimer’s disease,” said O’Banion. “This is yet another factor that NASA, which is clearly concerned about the health risks to its astronauts, will need to take into account as it plans future missions.”

Artist drawing of Landsat-5 in space (Image: USGS)

The longest operating Earth-observing satellite is about to be decommissioned by the US Geological Survey.

The USGS has begun the task of lowering Landsat-5 from its operational orbit.  The first series of maneuvers in that effort is likely to take place within the next month.

Landsat-5 was the fifth of seven satellites launched as part of the Landsat program, which has been acquiring satellite imagery of Earth since 1972.

Launched from California on March 1, 1984, Landsat-5 has circled Earth more than 150,000 times.

According to the USGS, which helps manage the mission, the satellite has been an extraordinary success, providing valuable contributions to the global record of land change.

Its original mission was only supposed to last three years, but Landsat-5 continued to deliver imagery and data for more than 25 more years beyond that.

The satellite experienced a number of problems over the years, but scientists and technicians managed to bring it back from the brink of failure.

This image of the abandoned city of Pripyat, home to the Chernobyl Nuclear Power Plant was taken by Landsat-5 three days after the April 26, 1986, nuclear accident. (NASA)

However, the recent failure of one of its gyroscopes proved to be one problem too many, finally bringing Landsat-5′s decades-long mission to an end.

“This is the end of an era for a remarkable satellite, and the fact that it flew for almost three decades is a testament to the NASA engineers and the USGS team who launched it and kept it flying well beyond its expected lifetime,” said Anne Castle, Department of the Interior assistant secretary for Water and Science. “The Landsat program is the gold standard of satellite observation, providing an invaluable public record of our planet that helps us tackle critical land, water, and environmental issues.”

Over more than a quarter of a century, Landsat-5  observed and sent back Earth imagery and data  reflecting the many changes which have taken place on our planet, not only from natural hazards and a changing climate, but also due to land use practices.

It observed the eruption of Mount Saint Helens, the 1991 Kuwaiti oil fires set by a fleeing Iraqi military, the 1986 Chernobyl nuclear disaster, as well as rainforest depletion, wildfires, floods, global crop production, and the expansion and retreat of the Earth’s ice shelves.

Image taken by Landsat-5 in 1991 shows inky-black smoke pouring from burning oil wells which were set afire by defeated Iraqi military forces as they retreated from Kuwait. (NASA)

“Any major event since 1984 that left a mark on this Earth larger than a football field was likely recorded by Landsat-5, whether it was a hurricane, a tsunami, a wildfire, deforestation, or an oil spill,” said USGS Director Marcia McNutt. “We look forward to a long and productive continuation of the Landsat program, but it is unlikely there will ever be another satellite that matches the outstanding longevity of Landsat-5.”

Landsat-5 observations have helped increase our understanding and awareness of the impact humans have on the land, according to the USGS.

With Landsat-5 out of commission, a number of Earth-observing satellites put into space by other governments and private companies, continue to operate.

Landsat-7, which launched in 1999, and the upcoming  Landsat-8 (LDCM), which launches in 2013, will take up where Landsat-5 left off, continuing to keep watch over an ever-changing planet.