Tag: molecules (page 2 of 4)

Astronomers Discover Ancient Dust Filled Galaxy ~ Debunks earlier theories that earliest galaxies had no dust only gas

March 3, 2015 / / 0 Comments


2262451851_21c1c74069


Excerpt from voicechronicle.com


Astronomers have discovered a dust-filled ancient galaxy from the very early universe, which debunks earlier theories that earliest galaxies had no dust but gas. Astronomers from the University of Copenhagen used the Very Large Telescope’s X-shooter instrument along with the Atacama Large Millimeter/submillimeter Array and discovered a galaxy, named Galaxy A1689-zD1, which is an ancient galaxy and far from Earth.
The astronomers stated that the galaxy which
they were surprised to discover is far more evolved system than expected. It had a fraction of dust similar to a very mature galaxy, such as the Milky Way. Such dust is vital to life, because it helps form planets, complex molecules and normal stars. 

According to the astronomers A1689-zD1 is only observable by virtue of its brightness being amplified more than nine times by a gravitational lens in the form of the spectacular galaxy cluster. Without the gravitational boost, the glow from this very faint galaxy would have been too weak to detect.

The astronomers stated that they are viewing A1689-zD1 when the Universe was only about 700 million years old, which is 5% of its present age. According to them, it is a relatively modest system — much less massive and luminous than many other objects that have been studied before at this stage in the early universe and hence a more typical example of a galaxy at that time.

A1689-zD1 is being observed as it was during the period of reionization, when the earliest stars brought with them a cosmic dawn, illuminating for the first time an immense and transparent universe and ending the extended stagnation of the Dark Ages. Expected to look like a newly formed system, the galaxy surprised the observers with its rich chemical complexity and abundance of interstellar dust.

Dust plays an extremely important role in the universe – both in the formation of planets and new stars.

Darach Watson, Associate Professor at Dark Cosmology Centre, University of Copenhagen, and the lead author of the study, said, “After confirming the galaxy’s distance using the VLT we realized it had previously been observed with ALMA. We didn’t expect to find much, but I can tell you we were all quite excited when we realized that not only had ALMA observed it, but that there was a clear detection. One of the main goals of the ALMA Observatory was to find galaxies in the early Universe from their cold gas and dust emissions — and here we had it!”

The researchers hope that future observations of a large number of distant galaxies could help unravel how frequently such evolved galaxies occur in this very early epoch of the history of the universe.

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Strange find on Titan sparks chatter about life

March 2, 2015 / / 0 Comments


Titan


Excerpt from nbcnews.com

Studies may suggest methane-based organic processes ... but maybe not  
New findings have roused a great deal of hoopla over the possibility of life on Saturn's moon Titan, which some news reports have further hyped up as hints of extraterrestrials.
However, scientists also caution that aliens might have nothing to do with these findings.

All this excitement is rooted in analyses of chemical data returned by NASA's Cassini spacecraft. One study suggested that hydrogen was flowing down through Titan's atmosphere and disappearing at the surface. Astrobiologist Chris McKay at NASA's Ames Research Center speculated that this could be a tantalizing hint that hydrogen is getting consumed by life.

"It's the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth," McKay said.

Another study investigating hydrocarbons on Titan's surface found a lack of acetylene, a compound that could be consumed as food by life that relies on liquid methane instead of liquid water to live.
"If these signs do turn out to be a sign of life, it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth," McKay said.
However, NASA scientists caution that aliens might not be involved at all.

"Scientific conservatism suggests that a biological explanation should be the last choice after all non-biological explanations are addressed," said Mark Allen, principal investigator with the NASA Astrobiology Institute Titan team. "We have a lot of work to do to rule out possible non-biological explanations. It is more likely that a chemical process, without biology, can explain these results."
McKay told Space.com that "both results are still preliminary."

To date, methane-based life forms are only speculative, with McKay proposing a set of conditions necessary for these kinds of organisms on Titan in 2005. Scientists have not yet detected this form of life anywhere, although there are liquid-water-based microbes on Earth that thrive on methane or produce it as a waste product. 

On Titan, where temperatures are around minus-290 degrees Fahrenheit (-179 degrees Celsius), any organisms would have to use a substance that is liquid as its medium for living processes. Water itself cannot do, because it is frozen solid on Titan's surface. The list of liquid candidates is very short — liquid methane and related molecules such as ethane. Previous studies have found Titan to have lakes of liquid methane.

Missing hydrogen? 

The dearth of hydrogen Cassini detected is consistent with conditions that could produce methane-based life, but do not conclusively prove its existence, cautioned researcher Darrell Strobel, a Cassini interdisciplinary scientist based at Johns Hopkins University in Baltimore. Strobel wrote the paper on hydrogen appearing online in the journal Icarus.

Strobel looked at densities of hydrogen in different parts of the atmosphere and at the surface. Previous models from scientists had predicted that hydrogen molecules, a byproduct of ultraviolet sunlight breaking apart acetylene and methane molecules in the upper atmosphere, should be distributed fairly evenly throughout the atmospheric layers.

Strobel's computer simulations suggest a hydrogen flow down to the surface at a rate of about 10,000 trillion trillion molecules per second. 

"It's as if you have a hose and you're squirting hydrogen onto the ground, but it's disappearing," Strobel said. "I didn't expect this result, because molecular hydrogen is extremely chemically inert in the atmosphere, very light and buoyant. It should 'float' to the top of the atmosphere and escape."

Strobel said it is not likely that hydrogen is being stored in a cave or underground space on Titan. An unknown mineral could be acting as a catalyst on Titan's surface to help convert hydrogen molecules and acetylene back to methane.

Although Allen commended Strobel, he noted "a more sophisticated model might be needed to look into what the flow of hydrogen is."

Consumed acetylene? 

Scientists had expected the sun's interactions with chemicals in the atmosphere to produce acetylene that falls down to coat Titan's surface. But when Cassini mapped hydrocarbons on Titan's surface, it detected no acetylene on the surface, according to findings appearing online in the Journal of Geophysical Research.

Instead of alien life on Titan, Allen said one possibility is that sunlight or cosmic rays are transforming the acetylene in icy aerosols in the atmosphere into more complex molecules that would fall to the ground with no acetylene signature.

In addition, Cassini detected an absence of water ice on Titan's surface, but loads of benzene and another as-yet-unidentified material, which appears to be an organic compound. The researchers said that a film of organic compounds is covering the water ice that makes up Titan's bedrock. This layer of hydrocarbons is at least a few millimeters to centimeters thick, but possibly much deeper in some places. 

"Titan's atmospheric chemistry is cranking out organic compounds that rain down on the surface so fast that even as streams of liquid methane and ethane at the surface wash the organics off, the ice gets quickly covered again," said Roger Clark, a Cassini team scientist based at the U.S. Geological Survey in Denver. "All that implies Titan is a dynamic place where organic chemistry is happening now."

All this speculation "is jumping the gun, in my opinion," Allen said.

"Typically in the search for the existence of life, one looks for the presence of evidence -- say, the methane seen in the atmosphere of Mars, which can't be made by normal photochemical processes," Allen added. "Here we're talking about absence of evidence rather than presence of evidence — missing hydrogen and acetylene — and oftentimes there are many non-life processes that can explain why things are missing."

These findings are "still a long way from evidence of life," McKay said. "But it could be interesting."

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What Would It Be Like to Live on Mercury?

February 24, 2015 / / 0 Comments


Mercury With Subtle Colors
Mercury's extreme temperatures and lack of an atmosphere would make it very difficult, if not impossible, for people to live on the planet. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington


Excerpt from  space.com
By Joseph Castro, Space.com Contributor


Have you ever wondered what it might be like to homestead on Mars or walk on the moons of Saturn? So did we. This is the first in Space.com's 12-part series on what it might be like to live on or near planets in our solar system, and beyond. Check back each week for the next space destination.
With its extreme temperature fluctuations, Mercury is not likely a planet that humans would ever want to colonize. But if we had the technology to survive on the planet closest to the sun, what would it be like to live there?

To date, only two spacecraft have visited Mercury. The first, Mariner 10, conducted a series of Mercury flybys in 1974, but the spacecraft only saw the lit half of the planet. NASA's MESSENGER spacecraft, on the other hand, conducted flybys and then entered Mercury's orbit — in March of 2013, images from the spacecraft allowed scientists to completely map the planet for the first time.



MESSENGER photos of Mercury show that the planet has water ice at its poles, which sit in permanent darkness. Mining this ice would be a good way to live off the land, but setting up bases at the poles might not be a good idea, said David Blewett, a participating scientist with the Messenger program.

"The polar regions would give you some respite from the strength of the sun on Mercury," Blewett told Space.com. "But, of course, it's really cold in those permanently shadowed areas where the ice is, and that presents its own challenge."

A better option, he said, would probably be to set up a home base not far from one of the ice caps, perhaps on a crater rim, and have a water mining operation at the pole.

Still, dealing with extreme temperatures on Mercury would likely be unavoidable: Daytime temperatures on the planet can reach 800 degrees Fahrenheit (430 degrees Celsius), while nighttime temperatures can drop down to minus 290 degrees Fahrenheit (minus 180 degrees Celsius).

Scientists once believed Mercury was tidally locked with the sun, meaning that one side of the planet always faces the sun because it takes the same amount of time to rotate around its axis as it does to revolve around the star. But we now know that Mercury's day lasts almost 59 Earth days and its year stretches for about 88 Earth days.

Interestingly, the sun has an odd path through the planet's sky over the course of Mercury's long day, because of the interaction between Mercury's spin rate and its highly elliptical orbit around the sun.

"It [the sun] rises in the east and moves across the sky, and then it pauses and moves backwards just a tad. It then resumes its motion towards the west and sunset," said Blewett, adding that the sun appears 2.5 times larger in Mercury's sky than it does in Earth's sky.

And during the day, Mercury's sky would appear black, not blue, because the planet has virtually no atmosphere to scatter the sun's light. "Here on Earth at sea level, the molecules of air are colliding billions of times per second," Blewett said. "But on Mercury, the atmosphere, or 'exosphere,' is so very rarefied that the atoms essentially never collide with other exosphere atoms." This lack of atmosphere also means that the stars wouldn't twinkle at night.



Without an atmosphere, Mercury doesn't have any weather; so while living on the planet, you wouldn't have to worry about devastating storms. And since the planet has no bodies of liquid water or active volcanoes, you'd be safe from tsunamis and eruptions.

But Mercury isn't devoid of natural disasters. "The surface is exposed to impacts of all sizes," Blewett said. It also may suffer from earthquakes due to compressive forces that are shrinking the planet (unlike Earth, Mercury doesn't have tectonic activity).

Mercury is about two-fifths the size of Earth, with a similar gravity to Mars, or about 38 percent of Earth's gravity. This means that you could jump three times as high on Mercury, and heavy objects would be easier to pick up, Blewett said. However, everything would still have the same mass and inertia, so you could be knocked over if someone threw a heavy object at you, he added.

Finally, you can forget about a smooth Skype call home: It takes at least 5 minutes for signals from Mercury to reach Earth, and vice versa.

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Mysterious plumes in Mars’ atmosphere baffle astronomers

February 17, 2015 / / 0 Comments




Excerpt from thespacereporter.com

Astronomers are baffled by images of plumes rising from Mars’ atmosphere in images taken by amateur astronomers in March and April 2012.

The plumes were present for about 10 days though their shapes and sizes changed rapidly during that time, from finger-like tendrils to spherical blobs.

Researchers have proposed several possible explanations for the plumes, which are discussed in an article just published in the journal Nature.

Each of the theories being considered poses problems. One theory, for instaqnce, proposes the plumes are caused by the same magnetic influence that causes the aurora borealis, or Northern Lights, on Earth. The movement of electrically charged particles from the Sun, driven by the solar wind towards Earth’s poles, results in these particles colliding with molecules of gas. These collisions produce the strange lights known as aurorae.

In the study, the researchers admit, “Mars aurorae have been observed near where the plume occurs, a region with a large anomaly in the crustal magnetic field that can drive the precipitation of solar wind particles into the atmosphere.”
The problem with this theory is this would only happen if the Sun released an exceptional amount of energetic particles during the time the plumes were seen. Yet the level of solar output in 2012 was nowhere near sufficient to release such a powerful stream of particles, the authors of the paper acknowledge.

They move on to consider another option, namely that the plumes might be clouds high in the Martian atmosphere.

A highly reflective cloud of either water ice, carbon dioxide ice, or dust particles could explain the plumes. But according to computer models, the presence of these clouds “would require exceptional deviations from standard atmospheric circulation models to explain cloud formations at such high altitudes,” explained the paper’s lead author, Agustin Sanchez-Lavega of the Universidad del Pais Vasco in Spain.

The plumes were seen approximately 120 miles (200 km) from Mars’ surface, which is problematic because the highest Martian clouds are seen is 60 miles (100 km) above the planet’s surface. The only way water can condense so far up is if the temperature in that part of Mars’ atmosphere drops 370 degrees Fahrenheit, or 50 degrees Kelvin, below its norm.

Condensation of carbon dioxide would require twice this temperature drop.

A third theory posits the flumes are caused by atmospheric dust. A wind powerful enough to transport dust 111 miles (180 km) above Mars’ surface could occur only around noon, when the Sun’s heat would be strong enough to create such wind currents.

However, the plumes were seen not at noon but in the mornings along the terminator that separates the planet’s day and night sides.
Recently, data from the Hubble Space Telescope was found showing the plumes back in 1997.

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ALMA uncovers stellar nurseries in the Sculptor Galaxy, 11.5 million light years from home

February 17, 2015 / / 0 Comments



ALMA uncovers stellar nurseries in the Sculptor Galaxy, 11.5 million light years from home
The Sculptor Galaxy


Excerpt from sciencerecorder.com

Starburst galaxies are named for their ability to convert gasses rapidly into new stars, at an accelerated speed that can sometimes be 1,000 times more rapid than your average spiral galaxy, such as the Milky Way. Why the disparity? In order to further investigate the reason that some galaxies seem to “burst” into being, whereas others take the better part of a few billion years, an international team of astronomers analyzed a cluster of star-forming gas clouds in the heart of NGC 253 – the Sculptor Galaxy, with the aid of the Atacama Large Millimeter/submillimeter Array (ALMA). The Sculptor Galaxy is among starburst galaxies closest to the Milky Way.

“All stars form in dense clouds of dust and gas,” said Adam Leroy, in an interview with Astronomy magazine. Leroy is an astronomer at Ohio State University in Columbus. “Until now, however, scientists struggled to see exactly what was going on inside starburst galaxies that distinguished them from other star-forming regions.”

Therefore, Leroy and his colleagues turn to the ALMA which is capable of examining star changing structures even in systems as distant as Sculptor. Already, they have successfully charted distribution and movement of various molecules within several clouds located at the Sculptor Galaxy’s core.

Because NGC 253, which is disk-shaped, is in the stages of a very intense starburst and located approximately 11.5 million light-years from home, it is the perfect target for study. ALMA picks it up with remarkable precision and resolution, so much so that the team was able to isolate and identify ten different stellar ‘nurseries,’ in which stars were in the process of forming. To appreciate the magnitude of this feat, it would have been impossible with previous telescopes, which blurred the regions together into one glow. 

“There is a class of galaxies and parts of galaxies, we call them starbursts, where we know that gas is just plain better at forming stars,” said Leroy. “To understand why, we took one of the nearest such regions and pulled it apart — layer by layer — to see what makes the gas in these places so much more efficient at star formation.”

More importantly, they recognized the distribution of several 40 millimeter-wavelength “signatures,” that given off by various molecules at the center of Sculptor Galaxy, signaling that a number of conditions were responsible for the development of these stars. This accounts for the diversity of the states of different stars corresponding to where they are found in star-forming clouds. One important compound, all too familiar and unwelcome on Earth, carbon monoxide (CO), correlates with massive envelopes of gases that are less dense within the stellar nurseries. Others, such as hydrogen cyanide (HCN), were present in the more dense reaches of active star formation. The rarer the molecules, for example, H13CN and H13CO+, suggest regions that are even denser.

Indeed, when the data was compared, researchers found that the gas clouds of the Sculptor Galaxy were ten times denser than those found in spiral galaxies, suggesting that because the clouds are so tightly packed, they can form star clusters much more rapidly than the Milky Way. At the same time, they give us further insight as to how stars are born, showing us the physical changes along the way, allowing astronomers a working model to compare with our own galaxy. 

“These differences have wide-ranging implications for how galaxies grow and evolve,” concluded Leroy. “What we would ultimately like to know is whether a starburst like Sculptor produces not just more stars, but different types of stars than a galaxy like the Milky Way. ALMA is bringing us much closer to that goal.”

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NASA Wants to Send a Submarine to Titan’s Seas ~ Video

February 13, 2015 / / 0 Comments



Titan


Excerpt from news.discovery.com

In a sneak peek of a possible future mission to Saturn’s moon Titan, NASA has showcased their vision of a robotic submersible that could explore the moon’s vast lakes of liquid methane and ethane.

Studying Titan is thought to be looking back in time at an embryonic Earth, only a lot colder. Titan is the only moon in the solar system to have a significant atmosphere and this atmosphere is known to possess its own methane cycle, like Earth’s water cycle. Methane exists in a liquid state, raining down on a landscape laced with hydrocarbons, forming rivers, valleys and seas.

Several seas have been extensively studied by NASA’s Cassini spacecraft during multiple flybys, some of which average a few meters deep, whereas others have depths of over 200 meters (660 feet) — the maximum depth at which Cassini’s radar instrument can penetrate.


So, if scientists are to properly explore Titan, they must find a way to dive into these seas to reveal their secrets.

At this year’s Innovative Advanced Concepts (NIAC) Symposium, a Titan submarine concept was showcased by NASA Glenn’s COMPASS Team and researchers from Applied Research Lab.

Envisaged as a possible mission to Titan’s largest sea, Kracken Mare, the autonomous submersible would be designed to make a 90 day, 2,000 kilometer (1,250 mile) voyage exploring the depths of this vast and very alien marine environment. As it would spend long periods under the methane sea’s surface, it would have to be powered by a radioisotope generator; a source that converts the heat produced by radioactive pellets into electricity, much like missions that are currently exploring space, like Cassini and Mars rover Curiosity.

Communicating with Earth would not be possible when the vehicle is submerged, so it would need to make regular ascents to the surface to transmit science data.

But Kracken Mare is not a tranquil lake fit for gentle sailing — it is known to have choppy waves and there is evidence of tides, all contributing to the challenge. Many of the engineering challenges have already been encountered when designing terrestrial submarines — robotic and crewed — but as these seas will be extremely cold (estimated to be close to the freezing point of methane, 90 Kelvin or -298 degrees Fahrenheit), a special piston-driven propulsion system will need to be developed and a nitrogen will be needed as ballast, for example.

This study is just that, a study, but the possibility of sending a submersible robot to another world would be as unprecedented as it is awesome.

Although it’s not clear at this early stage what the mission science would focus on, it would be interesting to sample the chemicals at different depths of Kracken Mare.

“Measurement of the trace organic components of the sea, which perhaps may exhibit prebiotic chemical evolution, will be an important objective, and a benthic sampler (a robotic grabber to sample sediment) would acquire and analyze sediment from the seabed,” the authors write (PDF). “These measurements, and seafloor morphology via sidescan sonar, may shed light on the historical cycles of filling and drying of Titan’s seas. Models suggest Titan’s active hydrological cycle may cause the north part of Kraken to be ‘fresher’ (more methane-rich) than the south, and the submarine’s long traverse will explore these composition variations.”

A decade after the European Huygens probe landed on the surface of Titan imaging the moon’s eerily foggy atmosphere, there have been few plans to go back to this tantalizing world. It would be incredible if, in the next few decades, we could send a mission back to Titan to directly sample what is at the bottom of its seas, exploring a region where the molecules for life’s chemistry may be found in abundance.



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NASA probe snaps amazing image of Ceres

February 6, 2015 / / 0 Comments



    NASA's Dawn space probe has taken the sharpest-yet image of Ceres, a dwarf planet in our solar system's asteroid belt.

    Excerpt from SPACE.com

    By Mike Wall  

    NASA's Dawn spacecraft has taken the sharpest-ever photos of Ceres, just a month before slipping into orbit around the mysterious dwarf planet.

    Dawn captured the new Ceres images Wednesday (Feb. 4), when the probe was 90,000 miles (145,000 kilometers) from the dwarf planet, the largest object in the main asteroid belt between Mars and Jupiter.

    On the night of March 5, Dawn will become the first spacecraft ever to orbit Ceres — and the first to circle two different solar system bodies beyond Earth. (Dawn orbited the protoplanet Vesta, the asteroid belt's second-largest denizen, from July 2011 through September 2012.) 

    "It's very exciting," Dawn mission director and chief engineer Marc Rayman, who's based at NASA's Jet Propulsion Laboratory in Pasadena, California, said of Dawn's impending arrival at Ceres. "This is a truly unique world, something that we've never seen before."


    The 590-mile-wide (950 km) Ceres was discovered by Italian astronomer Giuseppe Piazzi in 1801. It's the only dwarf planet in the asteroid belt, and contains about 30 percent of the belt's total mass. (For what it's worth, Vesta harbors about 8 percent of the asteroid belt's mass.)

    Despite Ceres' proximity (relative to other dwarf planets such as Pluto and Eris, anyway), scientists don't know much about the rocky world. But they think it contains a great deal of water, mostly in the form of ice. Indeed, Ceres may be about 30 percent water by mass, Rayman said.

    Ceres could even harbor lakes or oceans of liquid water beneath its frigid surface. Furthermore, in early 2014, researchers analyzing data gathered by Europe's Herschel Space Observatory announced that they had spotted a tiny plume of water vapor emanating from Ceres. The detection raised the possibility that internal heat drives cryovolcanism on the dwarf planet, as it does on Saturn's moon's Enceladus. (It's also possible that the "geyser" was caused by a meteorite impact, which exposed subsurface ice that quickly sublimated into space, researchers said).

    The interior of Ceres may thus possess liquid water and an energy source — two key criteria required for life as we know it to exist.
    Dawn is not equipped to search for signs of life. But the probe — which is carrying a camera, a visible and infrared mapping spectrometer and a gamma ray and neutron spectrometer — will give scientists great up-close looks at Ceres' surface, which in turn could shed light on what's happening down below. 

    For example, Dawn may see chemical signs of interactions between subsurface water, if it exists, and the surface, Rayman said.
    "That's the sort of the thing we would be looking for — surface structures or features that show up in the camera's eye, or something about the composition that's detectable by one of our multiple spectrometers that could show evidence," he told Space.com. "But if the water doesn't make it to the surface, and isn't in large enough reservoirs to show up in the gravity data, then maybe we won't find it."

    Dawn will also attempt to spot Ceres' water-vapor plume, if it still exists, by watching for sunlight scattered off water molecules above the dwarf planet. But that's going to be a very tough observation to make, Rayman said.

    "The density of the water [observed by Herschel] is less than the density of air even above the International Space Station," he said. "For a spacecraft designed to map solid surfaces of airless bodies, that is an extremely difficult measurement." 

    Merging onto the freeway

    Dawn is powered by low-thrust, highly efficient ion engines, so its arrival at Ceres will not be a nail-biting affair featuring a make-or-break engine burn, as most other probes' orbital insertions are.

    Indeed, as of Friday (Feb. 6), Dawn is closing in on Ceres at just 215 mph (346 km/h), Rayman said —and that speed will keep decreasing every day.

    "You take a gentle, curving route, and then you slowly and safely merge onto the freeway, traveling at the same speed as your destination," Rayman said. "Ion propulsion follows that longer, more gentle, more graceful route."

    Dawn won't start studying Ceres as soon as it arrives. The spacecraft will gradually work its way down to its first science orbit, getting there on April 23. Dawn will then begin its intensive observations of Ceres, from a vantage point just 8,400 miles (13,500 km) above the dwarf planet's surface.

    The science work will continue — from a series of increasingly closer-in orbits, including a low-altitude mapping orbit just 230 miles (375 km) from Ceres' surface — through June 30, 2016, when the $466 million Dawn mission is scheduled to end.
    Rayman can't wait to see what Dawn discovers.

    "After looking through telescopes at Ceres for more than 200 years, I just think it's really going to be exciting to see what this exotic, alien world looks like," he said. "We're finally going to learn about this place."

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    Neptune-Like Planets Could Transfom Into Habitable Worlds

    January 30, 2015 / / 0 Comments

    Strong irradiation from the host star can cause planets known as mini-Neptunes in the habitable zone to shed their gaseous envelopes and become potentially habitable worlds.Credit: Rodrigo Luger / NASA imagesExcerpt from sciencedaily.com Two ph...

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    Rosetta spacecraft raises new questions about comet’s origin

    January 23, 2015 / / 0 Comments

    Excerpt from news.asiaone.com CAPE CANAVERAL, US - Scientists using Europe's comet-orbiting Rosetta spacecraft have discovered that the complicated ancient body is coated with surprisingly simple organic molecules and surrounded by a changing clou...

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    Three Earth-like planets sighted around nearby star

    January 17, 2015 / / 0 Comments

    This artistic impression shows NASA's planet-hunting Kepler spacecraft operating in a new mission profile called K2. By analyzing data captured by the Kepler spacecraft, a UA-led team of researchers has discovered three new Earth-size planets orbiti...

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    Take Time to View Comet Lovejoy ~ Visable the Next Few Nights

    January 15, 2015 / / 0 Comments

    Comet Lovejoy


    Excerpt from issaquahpress.com


    Skywatchers should enjoy a good view of the Comet Lovejoy, or C/2014 Q2, which should be visible to the unaided eye under good conditions for the next few nights.

    “Should we get a clear sky, Comet Lovejoy should appear to the right side of the constellations Orion and Taurus, now visible in the southern sky,” Bruce Palmquist, Central Washington University professor of physics and science education, said in a news release.

    To see the comet, viewers should face due south, and look to the three stars that make up Orion’s belt.

    “The comet should appear a little to the right of Orion’s belt or the snout of Taurus the bull,” Palmquist said. “With binoculars or a small telescope, you should be able to see it clearly.

    “The best time to see the comet should be after 8 p.m.,” he continued. “And its best to find a place away from any city lights.”

    The comet head has a vivid green color, due to carbon molecules fluorescing in the sun’s ultraviolet light.

    The next time it will be visible to anyone on Earth will be roughly 10,000 years from now.

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    Discovery Sparks Interest – NASA’s Mission to Mars Gets Its Own New Show

    December 19, 2014 / / 0 Comments

    Excerpt from sciencetimes.comOften in the media, it's what's new and fresh that brings in the ratings. But what about looking for something potentially millions of years old? What if it wasn't on this planet even? Peak your interest yet? Well, if so...

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    Move Over Predator Alien: The human eye can see ‘invisible’ infrared light too

    December 3, 2014 / / 0 Comments


    The eye can detect light at wavelengths in the visual spectrum. Other wavelengths, such as infrared and ultraviolet, are supposed to be invisible to the human eye, but Washington University scientists have found that under certain conditions, it’s possible for us to see otherwise invisible infrared light. Image: Sara Dickherber

    Excerpt from
    news.wustl.edu
    By Jim Dryden

    Any science textbook will tell you we can’t see infrared light. Like X-rays and radio waves, infrared light waves are outside the visual spectrum. 

    But an international team of researchers co-led by scientists at Washington University School of Medicine in St. Louis has found that under certain conditions, the retina can sense infrared light after all. 

    Using cells from the retinas of mice and people, and powerful lasers that emit pulses of infrared light, the researchers found that when laser light pulses rapidly, light-sensing cells in the retina sometimes get a double hit of infrared energy. When that happens, the eye is able to detect light that falls outside the visible spectrum.

    The findings are published Dec. 1 in the Proceedings of the National Academy of Sciences (PNAS) Online Early Edition. The research was initiated after scientists on the research team reported seeing occasional flashes of green light while working with an infrared laser. Unlike the laser pointers used in lecture halls or as toys, the powerful infrared laser the scientists worked with emits light waves thought to be invisible to the human eye.

    “They were able to see the laser light, which was outside of the normal visible range, and we really wanted to figure out how they were able to sense light that was supposed to be invisible,” said Frans Vinberg, PhD, one of the study’s lead authors and a postdoctoral research associate in the Department of Ophthalmology and Visual Sciences at Washington University. 

    Vinberg, Kefalov and their colleagues examined the scientific literature and revisited reports of people seeing infrared light. They repeated previous experiments in which infrared light had been seen, and they analyzed such light from several lasers to see what they could learn about how and why it sometimes is visible.

    “We experimented with laser pulses of different durations that delivered the same total number of photons, and we found that the shorter the pulse, the more likely it was a person could see it,” Vinberg explained. “Although the length of time between pulses was so short that it couldn’t be noticed by the naked eye, the existence of those pulses was very important in allowing people to see this invisible light.”



    Robert Boston

    Kefalov’s team developed this adapter that allowed scientists to analyze retinal cells and photopigment molecules as they were exposed to infrared light. The device already is commercially available and in use at several vision research centers around the world.
    “The visible spectrum includes waves of light that are 400-720 nanometers long,” explained Kefalov, an associate professor of ophthalmology and visual sciences. “But if a pigment molecule in the retina is hit in rapid succession by a pair of photons that are 1,000 nanometers long, those light particles will deliver the same amount of energy as a single hit from a 500-nanometer photon, which is well within the visible spectrum. That’s how we are able to see it.”

    Robert Boston

    Frans Vinberg, PhD (left), and Vladimir J. Kefalov, PhD, sit in front of a tool they developed that allows them to detect light responses from retinal cells and photopigment molecules.

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