Thursday, May 17, 2012
Tuesday, May 15, 2012
9 NASA Astrona9 NASA Astronauts, 2 CIA Directors, 4 Presidents Believe In UFOs uts, 2 CIA Directors, 4 Presidents Believe In UFOs
Amazing that people who believe in UFOs get such stigma. They're in great company... check out this amazing collection of UFO believers, with VERIFIABLE quotes, like:
- Admiral Roscoe H. Hillenkoetter Director, CIA: "Unknown objects are operating under intelligent control... It is imperative that we learn where UFO's come from and what their purpose is..."
Wednesday, April 18, 2012
Tuesday, April 17, 2012
Wednesday, April 11, 2012
Using Planet Colors to Search for Alien Earths
Using Planet Colors to Search for Alien Earths
Planets around other stars probably exhibit a rainbow of colors every bit as diverse as those in our solar system. And astronomers would like to eventually harness color to learn more about exoplanets. Are they rocky or gaseous — or earthlike?
In a study recently accepted for publication in The Astrophysical Journal, a team led by NASA astronomer Lucy McFadden and UCLA graduate student Carolyn Crow describe a simple way to distinguish between the planets of our solar system based on color information. Earth, in particular, stands out clearly among the planets, like a blue jay in a flock of seagulls.
"The method we developed separates the planets out," Crow says. "It makes Earth look unique."
This suggests that someday, when we have the technology to gather light from individual exoplanets, astronomers could use color information to identify earthlike worlds. "Eventually, as telescopes get bigger, there will be the light-gathering power to look at the colors of planets around other stars," McFadden says. "Their colors will tell us which ones to study in more detail."
Earth the Exoplanet
The project began in 2008, when Crow teamed up with McFadden, her faculty mentor at the University of Maryland in College Park. McFadden currently heads university and post-doctoral programs at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
New color information about Earth, the moon, and Mars became available, thanks to NASA's Deep Impact spacecraft. En route to a planned encounter this November with Comet 103P/Hartley 2, Deep Impact observed Earth. The idea was to determine what our home looks like to alien astronomers and eventually use that insight to figure out how to spot earthlike worlds around other stars.
As Deep Impact cruised through space, its High Resolution Instrument (HRI) measured the intensity of Earth's light. HRI is an 11.8-inch (30 cm) telescope that feeds light through seven different color filters mounted on a revolving wheel. Each filter samples the incoming light at a different portion of the visible-light spectrum, from ultraviolet and blue to red and near-infrared. On May 28, 2008, Deep Impact even caught a glimpse of the moon's light as it crossed in front of Earth. Later, in 2009, HRI scoped Mars.
McFadden wondered what combination of color information from the filters would best distinguish Earth from the other planets and moons of the solar system. She recruited Crow to work on the project. Eight other researchers from NASA, the University of Maryland, the University of Washington (Seattle), and the Johns Hopkins University Applied Physics Lab also joined the team.
The Magic Mix
The Deep Impact color data covered Earth, the moon, and Mars. The relative amounts of light passing through the filters vary for each planet or moon, providing a kind of color fingerprint. To this the team added existing color information about Mercury, Venus, Jupiter, Saturn, Uranus, Neptune, and Saturn's moon Titan.
NASA researchers analyzed the light reflected by the planets and plotted the results on a "color-color" diagram. By plotting the ratios of red to green light as well as blue to green, the planets cluster into "color families." On the diagram, Earth is easily distinguishable from the other major planets. Credit: NASA/GSFC
A simple side-by-side comparison of color data on all the major planets was a confusing mess. The team finally found a combination of three different filters — one in the blue, one in the green, and one in the red — that highlights the differences between the planets.
On a special "color-color" diagram the team created, the planets cluster into groups based on similarities in the wavelengths of sunlight that their surfaces and atmospheres reflect. The gas giants Jupiter and Saturn huddle in one corner, Uranus and Neptune in a different one. The rocky inner planets Mars, Venus, and Mercury cluster off in their own corner of "color space."
But Earth is the true loner in color space. Its uniqueness traces to two factors. One is the scattering of blue light by the atmosphere. This is called Rayleigh scattering, after the English scientist who discovered it.
The other reason Earth stands out in color space is because it does not absorb a lot of infrared light. That's because our atmosphere is low in infrared-absorbing gases like methane and ammonia, compared to the gas giant planets Jupiter and Saturn.
"It is Earth's atmosphere that dominates the colors of Earth," Crow says. "It's the scattering of light in the ultraviolet and the absence of absorption in the infrared."
Colorful Future
Someday, the three-filter approach may provide a rough "first cut" look at exoplanet surfaces and atmospheres. "There are some things we can tell from the colors but there are some things that we can't quite tell without additional information," Crow says.
For example, if an exoplanet shows a similar color fingerprint to Earth's, it would not necessarily mean that the planet has the blue skies and vast oceans of our home. But it would tell us to look at that planet more closely.
And that would be an important first step toward making sense of the colorful complexity of the 490 (and counting) alien planets already discovered, and the scores more on the way.
A simple side-by-side comparison of color data on all the major planets was a confusing mess. The team finally found a combination of three different filters — one in the blue, one in the green, and one in the red — that highlights the differences between the planets.
On a special "color-color" diagram the team created, the planets cluster into groups based on similarities in the wavelengths of sunlight that their surfaces and atmospheres reflect. The gas giants Jupiter and Saturn huddle in one corner, Uranus and Neptune in a different one. The rocky inner planets Mars, Venus, and Mercury cluster off in their own corner of "color space."
But Earth is the true loner in color space. Its uniqueness traces to two factors. One is the scattering of blue light by the atmosphere. This is called Rayleigh scattering, after the English scientist who discovered it.
The other reason Earth stands out in color space is because it does not absorb a lot of infrared light. That's because our atmosphere is low in infrared-absorbing gases like methane and ammonia, compared to the gas giant planets Jupiter and Saturn.
"It is Earth's atmosphere that dominates the colors of Earth," Crow says. "It's the scattering of light in the ultraviolet and the absence of absorption in the infrared."
Colorful Future
Someday, the three-filter approach may provide a rough "first cut" look at exoplanet surfaces and atmospheres. "There are some things we can tell from the colors but there are some things that we can't quite tell without additional information," Crow says.
For example, if an exoplanet shows a similar color fingerprint to Earth's, it would not necessarily mean that the planet has the blue skies and vast oceans of our home. But it would tell us to look at that planet more closely.
And that would be an important first step toward making sense of the colorful complexity of the 490 (and counting) alien planets already discovered, and the scores more on the way.
NASA Astrobiologist Identifies New 'Extreme' Life Form
The end of a scientific journey -- started five years ago in a frozen tunnel deep below the Alaska tundra -- came in January for NASA astrobiologist Dr. Richard Hoover.
It proved a long, arduous journey for Hoover and his colleagues to complete the process of identifying a unique new life form. For the life form itself, a new bacterium dubbed Carnobacterium pleistocenium, the journey to discovery took much longer -- some 32,000 years.
The bacterium -- the first fully described, validated species ever found alive in ancient ice -- is NASA’s latest discovery of an "extremophile." Extremophiles are hardy life forms that exist and flourish in conditions hostile to most known organisms, from the potentially toxic chemical levels of salt-choked lakes and alkaline deserts to the extreme heat of deep-sea volcanoes. NASA and its partner organizations study the potential for life in such extreme zones to help prepare robotic probes and, eventually, human explorers to search other worlds for signs of life.
This search is a key element of the Vision for Space Exploration, the ambitious effort to return Americans to the Moon and to conduct robotic and human exploration of Mars and other worlds in our Solar System, which might conceal life forms unimaginable to us -- thriving in conditions few Earth species could tolerate.
In 1999 and 2000, Hoover, a researcher at NASA's Marshall Space Flight Center in Huntsville, Ala., time-traveled back to the Pleistocene via the U.S. Army’s Cold Regions Research and Engineering Laboratory, or "CRREL tunnel." The research site near Fox, Alaska, just north of Fairbanks, was carved by the Army Corps of Engineers in the mid-1960s to enable geologists and other scientists to study permafrost -- the mix of permanently frozen ice, soil and rock -- in preparation for construction in the early 1970s of the Trans-Alaska Oil Pipeline.
Hoover initially went to the CRREL tunnel in search of "psychrophiles" -- organisms that live only at extremely low temperatures. Hoover initially suspected the samples he collected there, from ice more than 30 millennia old, were diatoms, or microscopic, golden-brown algae. But closer study at the nearby University of Alaska revealed not diatoms but something much more interesting -- an assortment of bacterial cells, many of which came to life as soon as the ice thawed.
Hoover and his collaborator, microbiologist Dr. Elena Pikuta of the University of Alabama in Huntsville, studied the samples at the National Space Science and Technology Center, the research consortium operated by NASA and Alabama universities. They found the samples contained anaerobic bacteria that grew on sugars and proteins in total absence of oxygen. The bacteria had frozen near the end of the Pleistocene Age, which extended from about 1.8 million years ago to just 11,000 years ago -- and earned the new organism its name.
Further testing revealed the organism was not a psychrophile at all, but a "psychrotolerant" -- not an organism that thrives only at very cold temperatures, but one capable of enduring deep cold that resumes normal activity when temperatures rise.
Hoover, Pikuta and their collaborators -- Damien Marsic of the University of Alabama in Huntsville, Professor Asim Bej of the University of Alabama at Birmingham and Dr. Jane Tang and Dr. Paul Krader of the American Type Culture Collection in Manassas, Va. -- published their discovery in the January issue of the International Journal of Systematic and Evolutionary Microbiology. The bimonthly periodical, the official journal of record for new bacterial species, is produced by the Society for General Microbiology.
"Astrobiologists ask, 'Is life strictly terrestrial in origin, or is it a cosmic imperative, an undeniable, universal biological truth?' That possibility is central to our desire to explore the universe," Hoover said. "The existence of microorganisms in these harsh environments suggests -- but does not promise -- that we might one day discover similar life forms in the glaciers or permafrost of Mars or in the ice crust and oceans of Jupiter’s moon Europa."
Although many people think of bacteria merely as a cause of illness or decay, Hoover and Pikuta are quick to defend the organisms, which they call highly advanced marvels of natural engineering. There are approximately 7,000 validly described species of bacteria, though far more are surmised to exist. The vast majority are harmless to humans. Only a very few -- less than 1 percent of all known species -- are dangerous. And many, Hoover noted, are valuable to human life, aiding us in numerous ways: culturing wine, dairy products and other foods; assisting in the biological extraction of gold and other precious metals from ore wastes; and aiding production of valuable proteins and life-saving drugs.
Carnobacterium pleistocenium could even offer new medical breakthroughs. "The enzymes and proteins it possesses, which give it the ability to spring to life after such long periods of dormancy, might hold the key to long-term, cryogenic -- or very low temperature -- storage of living cells, tissues and perhaps even complex life forms," Hoover said.
"Life is far more diverse, and far more resistant to conditions we consider hostile, than was thought possible only a decade or two ago," he adds. "Studying these organisms helps us understand that life may be far more widespread in the cosmos than we previously imagined."
Living cultures of the new bacterium have been deposited in the American Type Culture Collection, in the Microbial Collection at the Pasteur Institute in Paris, and in the Japan Collection of Microorganisms in Saitama, Japan.
It proved a long, arduous journey for Hoover and his colleagues to complete the process of identifying a unique new life form. For the life form itself, a new bacterium dubbed Carnobacterium pleistocenium, the journey to discovery took much longer -- some 32,000 years.
The bacterium -- the first fully described, validated species ever found alive in ancient ice -- is NASA’s latest discovery of an "extremophile." Extremophiles are hardy life forms that exist and flourish in conditions hostile to most known organisms, from the potentially toxic chemical levels of salt-choked lakes and alkaline deserts to the extreme heat of deep-sea volcanoes. NASA and its partner organizations study the potential for life in such extreme zones to help prepare robotic probes and, eventually, human explorers to search other worlds for signs of life.
This search is a key element of the Vision for Space Exploration, the ambitious effort to return Americans to the Moon and to conduct robotic and human exploration of Mars and other worlds in our Solar System, which might conceal life forms unimaginable to us -- thriving in conditions few Earth species could tolerate.
In 1999 and 2000, Hoover, a researcher at NASA's Marshall Space Flight Center in Huntsville, Ala., time-traveled back to the Pleistocene via the U.S. Army’s Cold Regions Research and Engineering Laboratory, or "CRREL tunnel." The research site near Fox, Alaska, just north of Fairbanks, was carved by the Army Corps of Engineers in the mid-1960s to enable geologists and other scientists to study permafrost -- the mix of permanently frozen ice, soil and rock -- in preparation for construction in the early 1970s of the Trans-Alaska Oil Pipeline.
Hoover initially went to the CRREL tunnel in search of "psychrophiles" -- organisms that live only at extremely low temperatures. Hoover initially suspected the samples he collected there, from ice more than 30 millennia old, were diatoms, or microscopic, golden-brown algae. But closer study at the nearby University of Alaska revealed not diatoms but something much more interesting -- an assortment of bacterial cells, many of which came to life as soon as the ice thawed.
Hoover and his collaborator, microbiologist Dr. Elena Pikuta of the University of Alabama in Huntsville, studied the samples at the National Space Science and Technology Center, the research consortium operated by NASA and Alabama universities. They found the samples contained anaerobic bacteria that grew on sugars and proteins in total absence of oxygen. The bacteria had frozen near the end of the Pleistocene Age, which extended from about 1.8 million years ago to just 11,000 years ago -- and earned the new organism its name.
Further testing revealed the organism was not a psychrophile at all, but a "psychrotolerant" -- not an organism that thrives only at very cold temperatures, but one capable of enduring deep cold that resumes normal activity when temperatures rise.
Hoover, Pikuta and their collaborators -- Damien Marsic of the University of Alabama in Huntsville, Professor Asim Bej of the University of Alabama at Birmingham and Dr. Jane Tang and Dr. Paul Krader of the American Type Culture Collection in Manassas, Va. -- published their discovery in the January issue of the International Journal of Systematic and Evolutionary Microbiology. The bimonthly periodical, the official journal of record for new bacterial species, is produced by the Society for General Microbiology.
"Astrobiologists ask, 'Is life strictly terrestrial in origin, or is it a cosmic imperative, an undeniable, universal biological truth?' That possibility is central to our desire to explore the universe," Hoover said. "The existence of microorganisms in these harsh environments suggests -- but does not promise -- that we might one day discover similar life forms in the glaciers or permafrost of Mars or in the ice crust and oceans of Jupiter’s moon Europa."
Although many people think of bacteria merely as a cause of illness or decay, Hoover and Pikuta are quick to defend the organisms, which they call highly advanced marvels of natural engineering. There are approximately 7,000 validly described species of bacteria, though far more are surmised to exist. The vast majority are harmless to humans. Only a very few -- less than 1 percent of all known species -- are dangerous. And many, Hoover noted, are valuable to human life, aiding us in numerous ways: culturing wine, dairy products and other foods; assisting in the biological extraction of gold and other precious metals from ore wastes; and aiding production of valuable proteins and life-saving drugs.
Carnobacterium pleistocenium could even offer new medical breakthroughs. "The enzymes and proteins it possesses, which give it the ability to spring to life after such long periods of dormancy, might hold the key to long-term, cryogenic -- or very low temperature -- storage of living cells, tissues and perhaps even complex life forms," Hoover said.
"Life is far more diverse, and far more resistant to conditions we consider hostile, than was thought possible only a decade or two ago," he adds. "Studying these organisms helps us understand that life may be far more widespread in the cosmos than we previously imagined."
Living cultures of the new bacterium have been deposited in the American Type Culture Collection, in the Microbial Collection at the Pasteur Institute in Paris, and in the Japan Collection of Microorganisms in Saitama, Japan.
Kepler and the Search for Life in Our Galaxy
There are so many stars in our galaxy that even if planets with complex life (animals and plants) are rare – say one for every billion stars – there could still be dozens here in the Milky Way. But we are just beginning to learn about worlds beyond our solar system, called exoplanets, so we really don't have a good idea of what the chances are for advanced life. That's where NASA's Kepler mission comes in.
Currently, we have only one example of complex life –- our own. So we have to use conditions that give rise to this kind of life when we go looking for it elsewhere in the Universe. Essential ingredients in the recipe for life as we know it include liquid water; an energy source, such as sunlight or chemicals from volcanic activity; and a supply of raw materials in the form of critical elements like carbon, oxygen, hydrogen, and nitrogen, to name just a few. The most likely places where all the ingredients will be present are rocky planets, like Earth, that are within the habitable zone of their parent stars.
The habitable zone is where the temperature is just right for liquid water to exist on the surface of an exoplanet. If the planet is too close to its star, it will be too hot, and you'll end up with a world like Venus, where the oceans have boiled away. Too far away, however, and you get something like Mars, where most, if not all, of the water on the surface is frozen.
The Kepler mission seeks to detect Earth-like, i.e., rocky planets in our galaxy within the habitable zone of their parent stars, by looking for planetary transit events. These are situations where the planet passes in front of its star as seen from our point of view, slightly dimming the star's brightness. Since planetary transit events are fleeting, and it is unknown how common they may be, Kepler will continuously observe some 100,000 sun-like stars (in about 100 square degrees of the sky in the Cygnus region) for four years.
Currently, we have only one example of complex life –- our own. So we have to use conditions that give rise to this kind of life when we go looking for it elsewhere in the Universe. Essential ingredients in the recipe for life as we know it include liquid water; an energy source, such as sunlight or chemicals from volcanic activity; and a supply of raw materials in the form of critical elements like carbon, oxygen, hydrogen, and nitrogen, to name just a few. The most likely places where all the ingredients will be present are rocky planets, like Earth, that are within the habitable zone of their parent stars.
The habitable zone is where the temperature is just right for liquid water to exist on the surface of an exoplanet. If the planet is too close to its star, it will be too hot, and you'll end up with a world like Venus, where the oceans have boiled away. Too far away, however, and you get something like Mars, where most, if not all, of the water on the surface is frozen.
The Kepler mission seeks to detect Earth-like, i.e., rocky planets in our galaxy within the habitable zone of their parent stars, by looking for planetary transit events. These are situations where the planet passes in front of its star as seen from our point of view, slightly dimming the star's brightness. Since planetary transit events are fleeting, and it is unknown how common they may be, Kepler will continuously observe some 100,000 sun-like stars (in about 100 square degrees of the sky in the Cygnus region) for four years.
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| This is an artist's impression of a Jupiter-sized planet passing in front of its parent star. Such events are called transits. When the planet transits the star, the star's apparent brightness drops slightly for a short period. Through this technique, astronomers can use Kepler to search for planets across the galaxy by measuring periodic changes in a star's luminosity. |
Observing planetary transits is challenging, because the brightness changes are exceedingly small. For example, Earth is about one-hundredth the diameter of the sun, so from an alien point of view, when Earth passes in front of the sun, it obscures only a tiny area on the solar disk -- just one ten-thousandth. An alien watching Earth transit the sun would see our star's brightness drop by just one part in ten thousand. We expect similar faint eclipses when searching for Earth-like planets around sun-like stars. To detect such tiny changes in brightness, Kepler will be able to observe a brightness change as small as one part in one hundred thousand.
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| NASA's TRACE satellite captured this image of Venus (black disk) crossing the face of the Sun in 2004 as seen from Earth orbit. Before that, the last event occurred in 1882. The next Venus transit will be visible in 2012. Other challenges for Kepler are brightness changes that arise from a natural variation within the star itself, rather than from a transiting planet. If a brightness change repeats at regular intervals, it's more likely to be from an exoplanet, since its orbit will make it transit at the same periods. Scientists with the mission will need to see the same change at least twice before it's considered a possible exoplanet. Since the mission has a limited time to make its observations, if a transit takes more than a year to repeat, it will be difficult to confirm as an exoplanet. We can analyze a planetary transit event to discover basic characteristics of the planet. A large planet will block more starlight than a small one, so the size of the planet can be estimated by how much the star dims during the transit. A planet close to its star zips around it faster than one farther away, so the time between transits will give us an approximate distance of the planet from its star. The planet will also tug at the star with its gravity. Much as the siren of a speeding ambulance changes pitch as it passes by – higher when it's moving closer, and lower when it's moving away -- this gravitational pull will cause the colors (spectrum) of the star's light to shift slightly – more blue if the star is moving toward us, more red if the star is moving away. Astronomers can observe this color shift with instruments that separate the star's light into its component colors, called its spectrum. By observing the amount of color shift in the star's spectrum, astronomers can get the mass of the planet relative to its parent star – more massive planets have a greater pull and will cause a larger color shift. Most exoplanet detections so far have been made using this spectral shift. Such detections, however, tend to favor massive planets (about Jupiter’s size or larger). With current technology, it's extremely difficult to detect Earth-sized planets using this technique. Kepler will also be used to make discoveries about the stars themselves. There are many stars that are binaries (double stars). These binaries may exhibit eclipses. The Kepler mission data analysis program has a pipeline data processing that can discriminate the eclipsing binaries among the stars observed and will be analyzed accordingly. Binary stars, including cataclysmic variables (e.g., exploding stars such as novae) and intrinsic variable stars, including pulsating variables, that are observed with the Kepler satellite will present unprecedented opportunities to further astrophysical research. The Kepler observatory was placed in an Earth-following orbit March 6, 2009. This mission has been conceived by William Borucki and Dave Koch of NASA Ames Research Center, Moffett Field, Calif., and developed at NASA Ames. Kepler is a NASA Discovery mission. NASA Ames is the home organization of the science principal investigator, and is responsible for the ground system development, mission operations and science data analysis. NASA's Jet Propulsion Laboratory, Pasadena, Calif. manages the Kepler mission development. Ball Aerospace & Technologies Corp. of Boulder, Colo., is responsible for developing the Kepler flight system and supporting mission operations. |
NASA's Deep Impact Begins Hunt for Alien Worlds
NASA's Deep Impact spacecraft is aiming its largest telescope at five stars in a search for alien (exosolar) planets as it enters its extended mission, called Epoxi.
Deep Impact made history when the mission team directed an impactor from the spacecraft into comet Tempel 1 on July 4, 2005. NASA recently extended the mission, redirecting the spacecraft for a flyby of comet Hartley 2 on Oct. 11, 2010.
As it cruises toward the comet, Deep Impact will observe five nearby stars with "transiting exosolar planets," so named because the planet transits, or passes in front of, its star. The Epoxi team, led by University of Maryland astronomer Michael A'Hearn, directed the spacecraft to begin these observations Jan. 22. The planets were discovered earlier and are giant planets with massive atmospheres, like Jupiter in our solar system. They orbit their stars much closer than Earth does the sun, so they are hot and belong to the class of exosolar planets nicknamed "Hot Jupiters."
However, these giant planets may not be alone. If there are other worlds around these stars, they might also transit the star and be discovered by the spacecraft. Deep Impact can even find planets that don't transit, using a timing technique. Gravity from the unseen planets will pull on the transiting planets, altering their orbits and the timing of their transits.
"We're on the hunt for planets down to the size of Earth, orbiting some of our closest neighboring stars," said Epoxi Deputy Principal Investigator Drake Deming of NASA's Goddard Space Flight Center in Greenbelt, Md. Epoxi is a combination of the names for the two extended mission components: the exosolar planet observations, called Extrasolar Planet Observations and Characterization (Epoch), and the flyby of comet Hartley 2, called the Deep Impact Extended Investigation (Dixi). Goddard leads the Epoch component.
More than 200 exosolar planets have been discovered to date. Most of these are detected indirectly, by the gravitational pull they exert on their parent star. Directly observing exosolar planets by detecting the light reflected from them is very difficult, because a star's brilliance obscures light coming from any planets orbiting it.
However, sometimes the orbit of an exosolar world is aligned so that it eclipses its star as seen from Earth. In these rare cases, called transits, light from that planet can be seen directly.
"When the planet appears next to its star, your telescope captures their combined light. When the planet passes behind its star, your telescope only sees light from the star. By subtracting light from just the star from the combined light, you are left with light from the planet," said Deming, who is leading the search for exosolar worlds with Deep Impact. "We can analyze this light to discover what the atmospheres of these planets are like."
Deep Impact will also look back to observe Earth in visible and infrared wavelengths, allowing comparisons with future discoveries of Earth-like planets around other stars.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages Epoxi for NASA's Science Mission Directorate, Washington. The University of Maryland is the Principal Investigator institution. NASA Goddard leads the mission's exosolar planet observations. The spacecraft was built for NASA by Ball Aerospace & Technologies Corp., Boulder, Colo.
Deep Impact made history when the mission team directed an impactor from the spacecraft into comet Tempel 1 on July 4, 2005. NASA recently extended the mission, redirecting the spacecraft for a flyby of comet Hartley 2 on Oct. 11, 2010.
As it cruises toward the comet, Deep Impact will observe five nearby stars with "transiting exosolar planets," so named because the planet transits, or passes in front of, its star. The Epoxi team, led by University of Maryland astronomer Michael A'Hearn, directed the spacecraft to begin these observations Jan. 22. The planets were discovered earlier and are giant planets with massive atmospheres, like Jupiter in our solar system. They orbit their stars much closer than Earth does the sun, so they are hot and belong to the class of exosolar planets nicknamed "Hot Jupiters."
However, these giant planets may not be alone. If there are other worlds around these stars, they might also transit the star and be discovered by the spacecraft. Deep Impact can even find planets that don't transit, using a timing technique. Gravity from the unseen planets will pull on the transiting planets, altering their orbits and the timing of their transits.
"We're on the hunt for planets down to the size of Earth, orbiting some of our closest neighboring stars," said Epoxi Deputy Principal Investigator Drake Deming of NASA's Goddard Space Flight Center in Greenbelt, Md. Epoxi is a combination of the names for the two extended mission components: the exosolar planet observations, called Extrasolar Planet Observations and Characterization (Epoch), and the flyby of comet Hartley 2, called the Deep Impact Extended Investigation (Dixi). Goddard leads the Epoch component.
More than 200 exosolar planets have been discovered to date. Most of these are detected indirectly, by the gravitational pull they exert on their parent star. Directly observing exosolar planets by detecting the light reflected from them is very difficult, because a star's brilliance obscures light coming from any planets orbiting it.
However, sometimes the orbit of an exosolar world is aligned so that it eclipses its star as seen from Earth. In these rare cases, called transits, light from that planet can be seen directly.
"When the planet appears next to its star, your telescope captures their combined light. When the planet passes behind its star, your telescope only sees light from the star. By subtracting light from just the star from the combined light, you are left with light from the planet," said Deming, who is leading the search for exosolar worlds with Deep Impact. "We can analyze this light to discover what the atmospheres of these planets are like."
Deep Impact will also look back to observe Earth in visible and infrared wavelengths, allowing comparisons with future discoveries of Earth-like planets around other stars.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages Epoxi for NASA's Science Mission Directorate, Washington. The University of Maryland is the Principal Investigator institution. NASA Goddard leads the mission's exosolar planet observations. The spacecraft was built for NASA by Ball Aerospace & Technologies Corp., Boulder, Colo.
Alien World - NASA
Alien World
Scientists have made the first conclusive discovery of water vapor in the atmosphere of a planet beyond our solar system, or exoplanet.
This artist's rendering shows a gas-giant exoplanet transiting across the face of its star. Infrared analysis by NASA's Spitzer Space Telescope of this type of system provided the breakthrough.
The planet, HD 189733b, lies 63 light-years away in the constellation Vulpecula. It was discovered in 2005 as it transited its parent star.
This artist's rendering shows a gas-giant exoplanet transiting across the face of its star. Infrared analysis by NASA's Spitzer Space Telescope of this type of system provided the breakthrough.
The planet, HD 189733b, lies 63 light-years away in the constellation Vulpecula. It was discovered in 2005 as it transited its parent star.
Alien Sunset
Our solitary sunsets here on Earth might not be all that common in the grand scheme of things. New observations from NASA's Spitzer Space Telescope have revealed that mature planetary systems -- dusty disks of asteroids, comets and possibly planets --are more frequent around close-knit twin, or binary, stars than single stars like our sun. That means sunsets like the one portrayed in this artist's photo concept, and more famously in the movie "Star Wars," might be quite commonplace in the universe.
Binary and multiple-star systems are about twice as abundant as single-star systems in our galaxy, and, in theory, other galaxies. In a typical binary system, two stars of roughly similar masses twirl around each other like pair-figure skaters. In some systems, the two stars are very far apart and barely interact with each other. In other cases, the stellar twins are intricately linked, whipping around each other quickly due to the force of gravity.
Astronomers have discovered dozens of planets that orbit around a single member of a very wide stellar duo. Sunsets from these worlds would look like our own, and the second sun would just look like a bright star in the night sky.
But do planets exist in the tighter systems, where two suns would dip below a planet's horizon one by one? Unveiling planets in these systems is tricky, so astronomers used Spitzer to look for disks of swirling planetary debris instead. These disks are made of asteroids, comets and possibly planets. The rocky material in them bangs together and kicks up dust that Spitzer's infrared eyes can see. Our own solar system is swaddled in a similar type of disk.
Surprisingly, Spitzer found more debris disks around the tightest binaries it studied (about 20 stars) than in a comparable sample of single stars. About 60 percent of the tight binaries had disks, while the single stars only had about 20 percent. These snug binary systems are as close or closer than just three times the distance between Earth and the sun. And the disks in these systems were found to circumnavigate both members of the star pair, rather than just one.
Though follow-up studies are needed, the results could mean that planet formation is more common around extra-tight binary stars than single stars. Since these types of systems would experience double sunsets, the artistic view portrayed here might not be fiction.
The original sunset photo used in this artist's concept was taken by Robert Hurt of the Spitzer Science Center at the California Institute of Technology, Pasadena, Calif.
Binary and multiple-star systems are about twice as abundant as single-star systems in our galaxy, and, in theory, other galaxies. In a typical binary system, two stars of roughly similar masses twirl around each other like pair-figure skaters. In some systems, the two stars are very far apart and barely interact with each other. In other cases, the stellar twins are intricately linked, whipping around each other quickly due to the force of gravity.
Astronomers have discovered dozens of planets that orbit around a single member of a very wide stellar duo. Sunsets from these worlds would look like our own, and the second sun would just look like a bright star in the night sky.
But do planets exist in the tighter systems, where two suns would dip below a planet's horizon one by one? Unveiling planets in these systems is tricky, so astronomers used Spitzer to look for disks of swirling planetary debris instead. These disks are made of asteroids, comets and possibly planets. The rocky material in them bangs together and kicks up dust that Spitzer's infrared eyes can see. Our own solar system is swaddled in a similar type of disk.
Surprisingly, Spitzer found more debris disks around the tightest binaries it studied (about 20 stars) than in a comparable sample of single stars. About 60 percent of the tight binaries had disks, while the single stars only had about 20 percent. These snug binary systems are as close or closer than just three times the distance between Earth and the sun. And the disks in these systems were found to circumnavigate both members of the star pair, rather than just one.
Though follow-up studies are needed, the results could mean that planet formation is more common around extra-tight binary stars than single stars. Since these types of systems would experience double sunsets, the artistic view portrayed here might not be fiction.
The original sunset photo used in this artist's concept was taken by Robert Hurt of the Spitzer Science Center at the California Institute of Technology, Pasadena, Calif.
NASA Rover Finds Clue To Mars' Past And Environment For Life
NASA Rover Finds Clue To Mars' Past And Environment For Life
PASADENA, Calif. -- Rocks examined by NASA's Spirit Mars Rover hold evidence of a wet, non-acidic ancient environment that may have been favorable for life. Confirming this mineral clue took four years of analysis by several scientists.
An outcrop that Spirit examined in late 2005 revealed high concentrations of carbonate, which originates in wet, near-neutral conditions, but dissolves in acid. The ancient water indicated by this find was not acidic.
NASA's rovers have found other evidence of formerly wet Martian environments. However the data for those environments indicate conditions that may have been acidic. In other cases, the conditions were definitely acidic, and therefore less favorable as habitats for life.
Laboratory tests helped confirm the carbonate identification. The findings were published online Thursday, June 3 by the journal Science.
"This is one of the most significant findings by the rovers," said Steve Squyres of Cornell University in Ithaca, N.Y. Squyres is principal investigator for the Mars twin rovers, Spirit and Opportunity, and a co-author of the new report. "A substantial carbonate deposit in a Mars outcrop tells us that conditions that could have been quite favorable for life were present at one time in that place. "
Spirit inspected rock outcrops, including one scientists called Comanche, along the rover's route from the top of Husband Hill to the vicinity of the Home Plate plateau which Spirit has studied since 2006. Magnesium iron carbonate makes up about one-fourth of the measured volume in Comanche. That is a tenfold higher concentration than any previously identified for carbonate in a Martian rock.
"We used detective work combining results from three spectrometers to lock this down," said Dick Morris, lead author of the report and a member of a rover science team at NASA's Johnson Space Center in Houston."The instruments gave us multiple, interlocking ways of confirming the magnesium iron carbonate, with a good handle on how much there is."
Massive carbonate deposits on Mars have been sought for years without much success. Numerous channels apparently carved by flows of liquid water on ancient Mars suggest the planet was formerly warmer, thanks to greenhouse warming from a thicker atmosphere than exists now. The ancient, dense Martian atmosphere was probably rich in carbon dioxide, because that gas makes up nearly all the modern, very thin atmosphere.
It is important to determine where most of the carbon dioxide went. Some theorize it departed to space. Others hypothesize that it left the atmosphere by the mixing of carbon dioxide with water under conditions that led to forming carbonate minerals. That possibility, plus finding small amounts of carbonate in meteorites that originated from Mars, led to expectations in the 1990s that carbonate would be abundant on Mars. However, mineral-mapping spectrometers on orbiters since then have found evidence of localized carbonate deposits in only one area, plus small amounts distributed globally in Martian dust.
Morris suspected iron-bearing carbonate at Comanche years ago from inspection of the rock with Spirit's Moessbauer Spectrometer, which provides information about iron-containing minerals. Confirming evidence from other instruments emerged slowly. The instrument with the best capability for detecting carbonates, the Miniature Thermal Emission Spectrometer, had its mirror contaminated with dust earlier in 2005, during a wind event that also cleaned Spirit's solar panels.
"It was like looking through dirty glasses," said Steve Ruff of Arizona State University in Tempe, Ariz., another co-author of the report. "We could tell there was something very different about Comanche compared with other outcrops we had seen, but we couldn't tell what it was until we developed a correction method to account for the dust on the mirror."
Spirit's Alpha Particle X-ray Spectrometer instrument detected a high concentration of light elements, a group including carbon and oxygen, that helped quantify the carbonate content.
The rovers landed on Mars in January 2004 for missions originally planned to last three months. Spirit has been out of communication since March 22 and is in a low-power hibernation status during Martian winter. Opportunity is making steady progress toward a large crater, Endeavour, which is about seven miles away.
An outcrop that Spirit examined in late 2005 revealed high concentrations of carbonate, which originates in wet, near-neutral conditions, but dissolves in acid. The ancient water indicated by this find was not acidic.
NASA's rovers have found other evidence of formerly wet Martian environments. However the data for those environments indicate conditions that may have been acidic. In other cases, the conditions were definitely acidic, and therefore less favorable as habitats for life.
Laboratory tests helped confirm the carbonate identification. The findings were published online Thursday, June 3 by the journal Science.
"This is one of the most significant findings by the rovers," said Steve Squyres of Cornell University in Ithaca, N.Y. Squyres is principal investigator for the Mars twin rovers, Spirit and Opportunity, and a co-author of the new report. "A substantial carbonate deposit in a Mars outcrop tells us that conditions that could have been quite favorable for life were present at one time in that place. "
Spirit inspected rock outcrops, including one scientists called Comanche, along the rover's route from the top of Husband Hill to the vicinity of the Home Plate plateau which Spirit has studied since 2006. Magnesium iron carbonate makes up about one-fourth of the measured volume in Comanche. That is a tenfold higher concentration than any previously identified for carbonate in a Martian rock.
"We used detective work combining results from three spectrometers to lock this down," said Dick Morris, lead author of the report and a member of a rover science team at NASA's Johnson Space Center in Houston."The instruments gave us multiple, interlocking ways of confirming the magnesium iron carbonate, with a good handle on how much there is."
Massive carbonate deposits on Mars have been sought for years without much success. Numerous channels apparently carved by flows of liquid water on ancient Mars suggest the planet was formerly warmer, thanks to greenhouse warming from a thicker atmosphere than exists now. The ancient, dense Martian atmosphere was probably rich in carbon dioxide, because that gas makes up nearly all the modern, very thin atmosphere.
It is important to determine where most of the carbon dioxide went. Some theorize it departed to space. Others hypothesize that it left the atmosphere by the mixing of carbon dioxide with water under conditions that led to forming carbonate minerals. That possibility, plus finding small amounts of carbonate in meteorites that originated from Mars, led to expectations in the 1990s that carbonate would be abundant on Mars. However, mineral-mapping spectrometers on orbiters since then have found evidence of localized carbonate deposits in only one area, plus small amounts distributed globally in Martian dust.
Morris suspected iron-bearing carbonate at Comanche years ago from inspection of the rock with Spirit's Moessbauer Spectrometer, which provides information about iron-containing minerals. Confirming evidence from other instruments emerged slowly. The instrument with the best capability for detecting carbonates, the Miniature Thermal Emission Spectrometer, had its mirror contaminated with dust earlier in 2005, during a wind event that also cleaned Spirit's solar panels.
"It was like looking through dirty glasses," said Steve Ruff of Arizona State University in Tempe, Ariz., another co-author of the report. "We could tell there was something very different about Comanche compared with other outcrops we had seen, but we couldn't tell what it was until we developed a correction method to account for the dust on the mirror."
Spirit's Alpha Particle X-ray Spectrometer instrument detected a high concentration of light elements, a group including carbon and oxygen, that helped quantify the carbonate content.
The rovers landed on Mars in January 2004 for missions originally planned to last three months. Spirit has been out of communication since March 22 and is in a low-power hibernation status during Martian winter. Opportunity is making steady progress toward a large crater, Endeavour, which is about seven miles away.
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UFO Sightings Skyrocket Into 2012
During the first week of 2012, UFO reports streamed in from around the world as numerous eyewitnesses described and videotaped strange things in the sky.
Whether they were balloons, conventional aircraft or misidentified astronomical objects, the new year of UFO sightings is off and running as the worldwide proliferation of digital video cameras and phone cams makes it easier than ever to photograph unusual sights in the sky above us.
The Colorado-based Mutual UFO Network, the largest UFO investigative organization in the world, received many reports of UFOs during the first week of the year from eyewitnesses in 36 out of 50 states.
The 14 states that haven't reported in so far are Alaska, Arkansas, Delaware, Hawaii, Maine, Minnesota, Montana, Nebraska, North Dakota, Rhode Island, South Dakota, Washington, Wisconsin and Wyoming -- but the year is young.
WHAT'S THIS OBJECT THAT SLOWLY FELL OUT OF THE SKY IN JAPAN?
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"For the entire month of January 2011, MUFON recorded around 500 reports, and we're already up to 233 after just the first week of 2012," said MUFON international director Clifford Clift.
"For December, we had 810, compared to about 500 in December 2010," Clift told The Huffington Post.
"Last year, we averaged over 6,000 total sightings, and if it continues at this pace, we'll be up 50 percent, with about 10 percent of those reports ending up as unexplained after our investigation," he said.
According to New Zealand's WeatherWatch.co.nz, in the first 24 hours of the new year, it received "almost 80 reports and they're still flooding in at about 10 an hour."
"Many people around the world have been outside celebrating the new year. In the U.S., where most of the sightings came from, conditions were fairly mild and dry in many areas, so more people were outside to see things," weather analyst Philip Duncan said in a statement.
WATCH THESE UNUSUAL OBJECTS IN THE SKY OVER CAMPINAS, BRAZIL ON JAN. 3:
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A group of twinkling cylindrical lights was videotaped over Campinas, Brazil, on Jan. 3, according tolatestufosightings.net, which keeps track of on-going UFO reports, including the following:
Jan. 3: Two slow-moving, bright flying objects were recorded over Sinaloa, Mexico.
Jan. 4: The skies above North Carolina were the subject of videotape of unexplained bright objects.
Jan. 5: A white-colored globe was captured on video over Mesa, Ariz.
Jan. 6: A strange, bright object was videotaped as it fell out of the sky over Wakayama, Japan.
Jan. 7: Some high-altitude glowing orbs were caught on videotape over San Antonio, Texas.
Jan. 7: On the other side of the world, two bright objects were videotaped above Minsk, Belarus.
WeatherWatch suggests that what people are seeing are either meteorites, slow-moving, orange-colored Chinese lanterns or normal aircraft.
Most UFOs turn out to be explainable objects, but with the ever-present small remainder of the unexplained, MUFON's Clift is optimistic about how the rest of the year may unfold.
"One reason why I think it's going to be a good year is because people are looking at the sky a lot more and now they know where to report UFOs, and they're reporting them like crazy," he explained.
UFOS ARE OFTEN MISIDENTIFIED OBJECTS LIKE THESE:
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