Tag: cold (page 3 of 7)

8 possible explanations for those bright spots on dwarf planet Ceres

Ceres  Excerpt from cnet.com It's a real-life mystery cliffhanger. We've come up with a list of possible reasons a large crater on the biggest object in the asteroid belt looks lit up like a Christmas tree.  We could be approachin...

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


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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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What Would It Be Like to Live on Mercury?


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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Why science is so hard to believe?

 
In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.


Excerpt from 


There’s a scene in Stanley Kubrick’s comic masterpiece “Dr. Strangelove” in which Jack D. Ripper, an American general who’s gone rogue and ordered a nuclear attack on the Soviet Union, unspools his paranoid worldview — and the explanation for why he drinks “only distilled water, or rainwater, and only pure grain alcohol” — to Lionel Mandrake, a dizzy-with-anxiety group captain in the Royal Air Force.
Ripper: “Have you ever heard of a thing called fluoridation? Fluoridation of water?”
Mandrake: “Ah, yes, I have heard of that, Jack. Yes, yes.”Ripper: “Well, do you know what it is?”
Mandrake: “No. No, I don’t know what it is, no.”
Ripper: “Do you realize that fluoridation is the most monstrously conceived and dangerous communist plot we have ever had to face?” 

The movie came out in 1964, by which time the health benefits of fluoridation had been thoroughly established and anti-fluoridation conspiracy theories could be the stuff of comedy. Yet half a century later, fluoridation continues to incite fear and paranoia. In 2013, citizens in Portland, Ore., one of only a few major American cities that don’t fluoridate, blocked a plan by local officials to do so. Opponents didn’t like the idea of the government adding “chemicals” to their water. They claimed that fluoride could be harmful to human health.

Actually fluoride is a natural mineral that, in the weak concentrations used in public drinking-water systems, hardens tooth enamel and prevents tooth decay — a cheap and safe way to improve dental health for everyone, rich or poor, conscientious brushers or not. That’s the scientific and medical consensus.
To which some people in Portland, echoing anti-fluoridation activists around the world, reply: We don’t believe you.
We live in an age when all manner of scientific knowledge — from the safety of fluoride and vaccines to the reality of climate change — faces organized and often furious opposition. Empowered by their own sources of information and their own interpretations of research, doubters have declared war on the consensus of experts. There are so many of these controversies these days, you’d think a diabolical agency had put something in the water to make people argumentative.
Science doubt has become a pop-culture meme. In the recent movie “Interstellar,” set in a futuristic, downtrodden America where NASA has been forced into hiding, school textbooks say the Apollo moon landings were faked.


The debate about mandated vaccinations has the political world talking. A spike in measles cases nationwide has President Obama, lawmakers and even potential 2016 candidates weighing in on the vaccine controversy. (Pamela Kirkland/The Washington Post)
In a sense this is not surprising. Our lives are permeated by science and technology as never before. For many of us this new world is wondrous, comfortable and rich in rewards — but also more complicated and sometimes unnerving. We now face risks we can’t easily analyze.
We’re asked to accept, for example, that it’s safe to eat food containing genetically modified organisms (GMOs) because, the experts point out, there’s no evidence that it isn’t and no reason to believe that altering genes precisely in a lab is more dangerous than altering them wholesale through traditional breeding. But to some people, the very idea of transferring genes between species conjures up mad scientists running amok — and so, two centuries after Mary Shelley wrote “Frankenstein,” they talk about Frankenfood.
The world crackles with real and imaginary hazards, and distinguishing the former from the latter isn’t easy. Should we be afraid that the Ebola virus, which is spread only by direct contact with bodily fluids, will mutate into an airborne super-plague? The scientific consensus says that’s extremely unlikely: No virus has ever been observed to completely change its mode of transmission in humans, and there’s zero evidence that the latest strain of Ebola is any different. But Google “airborne Ebola” and you’ll enter a dystopia where this virus has almost supernatural powers, including the power to kill us all.
In this bewildering world we have to decide what to believe and how to act on that. In principle, that’s what science is for. “Science is not a body of facts,” says geophysicist Marcia McNutt, who once headed the U.S. Geological Survey and is now editor of Science, the prestigious journal. “Science is a method for deciding whether what we choose to believe has a basis in the laws of nature or not.”
The scientific method leads us to truths that are less than self-evident, often mind-blowing and sometimes hard to swallow. In the early 17th century, when Galileo claimed that the Earth spins on its axis and orbits the sun, he wasn’t just rejecting church doctrine. He was asking people to believe something that defied common sense — because it sure looks like the sun’s going around the Earth, and you can’t feel the Earth spinning. Galileo was put on trial and forced to recant. Two centuries later, Charles Darwin escaped that fate. But his idea that all life on Earth evolved from a primordial ancestor and that we humans are distant cousins of apes, whales and even deep-sea mollusks is still a big ask for a lot of people.
Even when we intellectually accept these precepts of science, we subconsciously cling to our intuitions — what researchers call our naive beliefs. A study by Andrew Shtulman of Occidental College showed that even students with an advanced science education had a hitch in their mental gait when asked to affirm or deny that humans are descended from sea animals and that the Earth goes around the sun. Both truths are counterintuitive. The students, even those who correctly marked “true,” were slower to answer those questions than questions about whether humans are descended from tree-dwelling creatures (also true but easier to grasp) and whether the moon goes around the Earth (also true but intuitive).
Shtulman’s research indicates that as we become scientifically literate, we repress our naive beliefs but never eliminate them entirely. They nest in our brains, chirping at us as we try to make sense of the world.
Most of us do that by relying on personal experience and anecdotes, on stories rather than statistics. We might get a prostate-specific antigen test, even though it’s no longer generally recommended, because it caught a close friend’s cancer — and we pay less attention to statistical evidence, painstakingly compiled through multiple studies, showing that the test rarely saves lives but triggers many unnecessary surgeries. Or we hear about a cluster of cancer cases in a town with a hazardous-waste dump, and we assume that pollution caused the cancers. Of course, just because two things happened together doesn’t mean one caused the other, and just because events are clustered doesn’t mean they’re not random. Yet we have trouble digesting randomness; our brains crave pattern and meaning.
Even for scientists, the scientific method is a hard discipline. They, too, are vulnerable to confirmation bias — the tendency to look for and see only evidence that confirms what they already believe. But unlike the rest of us, they submit their ideas to formal peer review before publishing them. Once the results are published, if they’re important enough, other scientists will try to reproduce them — and, being congenitally skeptical and competitive, will be very happy to announce that they don’t hold up. Scientific results are always provisional, susceptible to being overturned by some future experiment or observation. Scientists rarely proclaim an absolute truth or an absolute certainty. Uncertainty is inevitable at the frontiers of knowledge.
That provisional quality of science is another thing a lot of people have trouble with. To some climate-change skeptics, for example, the fact that a few scientists in the 1970s were worried (quite reasonably, it seemed at the time) about the possibility of a coming ice age is enough to discredit what is now the consensus of the world’s scientists: The planet’s surface temperature has risen by about 1.5 degrees Fahrenheit in the past 130 years, and human actions, including the burning of fossil fuels, are extremely likely to have been the dominant cause since the mid-20th century.
It’s clear that organizations funded in part by the fossil-fuel industry have deliberately tried to undermine the public’s understanding of the scientific consensus by promoting a few skeptics. The news media gives abundant attention to such mavericks, naysayers, professional controversialists and table thumpers. The media would also have you believe that science is full of shocking discoveries made by lone geniuses. Not so. The (boring) truth is that science usually advances incrementally, through the steady accretion of data and insights gathered by many people over many years. So it has with the consensus on climate change. That’s not about to go poof with the next thermometer reading.
But industry PR, however misleading, isn’t enough to explain why so many people reject the scientific consensus on global warming.
The “science communication problem,” as it’s blandly called by the scientists who study it, has yielded abundant new research into how people decide what to believe — and why they so often don’t accept the expert consensus. It’s not that they can’t grasp it, according to Dan Kahan of Yale University. In one study he asked 1,540 Americans, a representative sample, to rate the threat of climate change on a scale of zero to 10. Then he correlated that with the subjects’ science literacy. He found that higher literacy was associated with stronger views — at both ends of the spectrum. Science literacy promoted polarization on climate, not consensus. According to Kahan, that’s because people tend to use scientific knowledge to reinforce their worldviews.
Americans fall into two basic camps, Kahan says. Those with a more “egalitarian” and “communitarian” mind-set are generally suspicious of industry and apt to think it’s up to something dangerous that calls for government regulation; they’re likely to see the risks of climate change. In contrast, people with a “hierarchical” and “individualistic” mind-set respect leaders of industry and don’t like government interfering in their affairs; they’re apt to reject warnings about climate change, because they know what accepting them could lead to — some kind of tax or regulation to limit emissions.
In the United States, climate change has become a litmus test that identifies you as belonging to one or the other of these two antagonistic tribes. When we argue about it, Kahan says, we’re actually arguing about who we are, what our crowd is. We’re thinking: People like us believe this. People like that do not believe this.
Science appeals to our rational brain, but our beliefs are motivated largely by emotion, and the biggest motivation is remaining tight with our peers. “We’re all in high school. We’ve never left high school,” says Marcia McNutt. “People still have a need to fit in, and that need to fit in is so strong that local values and local opinions are always trumping science. And they will continue to trump science, especially when there is no clear downside to ignoring science.”
Meanwhile the Internet makes it easier than ever for science doubters to find their own information and experts. Gone are the days when a small number of powerful institutions — elite universities, encyclopedias and major news organizations — served as gatekeepers of scientific information. The Internet has democratized it, which is a good thing. But along with cable TV, the Web has also made it possible to live in a “filter bubble” that lets in only the information with which you already agree.
How to penetrate the bubble? How to convert science skeptics? Throwing more facts at them doesn’t help. Liz Neeley, who helps train scientists to be better communicators at an organization called Compass, says people need to hear from believers they can trust, who share their fundamental values. She has personal experience with this. Her father is a climate-change skeptic and gets most of his information on the issue from conservative media. In exasperation she finally confronted him: “Do you believe them or me?” She told him she believes the scientists who research climate change and knows many of them personally. “If you think I’m wrong,” she said, “then you’re telling me that you don’t trust me.” Her father’s stance on the issue softened. But it wasn’t the facts that did it.
If you’re a rationalist, there’s something a little dispiriting about all this. In Kahan’s descriptions of how we decide what to believe, what we decide sometimes sounds almost incidental. Those of us in the science-communication business are as tribal as anyone else, he told me. We believe in scientific ideas not because we have truly evaluated all the evidence but because we feel an affinity for the scientific community. When I mentioned to Kahan that I fully accept evolution, he said: “Believing in evolution is just a description about you. It’s not an account of how you reason.”
Maybe — except that evolution is real. Biology is incomprehensible without it. There aren’t really two sides to all these issues. Climate change is happening. Vaccines save lives. Being right does matter — and the science tribe has a long track record of getting things right in the end. Modern society is built on things it got right.
Doubting science also has consequences, as seen in recent weeks with the measles outbreak that began in California. The people who believe that vaccines cause autism — often well educated and affluent, by the way — are undermining “herd immunity” to such diseases as whooping cough and measles. The anti-vaccine movement has been going strong since a prestigious British medical journal, the Lancet, published a study in 1998 linking a common vaccine to autism. The journal later retracted the study, which was thoroughly discredited. But the notion of a vaccine-autism connection has been endorsed by celebrities and reinforced through the usual Internet filters. (Anti-vaccine activist and actress Jenny McCarthy famously said on “The Oprah Winfrey Show,” “The University of Google is where I got my degree from.”)
In the climate debate, the consequences of doubt are likely to be global and enduring. Climate-change skeptics in the United States have achieved their fundamental goal of halting legislative action to combat global warming. They haven’t had to win the debate on the merits; they’ve merely had to fog the room enough to keep laws governing greenhouse gas emissions from being enacted.
Some environmental activists want scientists to emerge from their ivory towers and get more involved in the policy battles. Any scientist going that route needs to do so carefully, says Liz Neeley. “That line between science communication and advocacy is very hard to step back from,” she says. In the debate over climate change, the central allegation of the skeptics is that the science saying it’s real and a serious threat is politically tinged, driven by environmental activism and not hard data. That’s not true, and it slanders honest scientists. But the claim becomes more likely to be seen as plausible if scientists go beyond their professional expertise and begin advocating specific policies.
It’s their very detachment, what you might call the cold-bloodedness of science, that makes science the killer app. It’s the way science tells us the truth rather than what we’d like the truth to be. Scientists can be as dogmatic as anyone else — but their dogma is always wilting in the hot glare of new research. In science it’s not a sin to change your mind when the evidence demands it. For some people, the tribe is more important than the truth; for the best scientists, the truth is more important than the tribe.

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



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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Moonquakes and blazing heat: What would life really be like on the Moon?


Lunar Base Made with 3D Printing


Excerpt from space.com

The idea of building a lunar outpost has long captured people's imaginations. But what would it really be like to live on the moon?
Space exploration has long focused on the moon, with Earth's satellite the setting for a number of significant missions. A 1959 Soviet spacecraft photographed the moon's far side for the first time, and in 1969, NASA landed people on the lunar surface for the first time. Numerous missions followed, including NASA's Lunar Reconnaissance Orbiter that beamed home the highest-resolution topographical lunar map to date, covering 98.2 percent of the moon's surface. 

Altogether, data beamed back from numerous missions suggest that no place on the moon would be a pleasant place to live, at least compared with Earth. Lunar days stretch for about 14 Earth days with average temperatures of 253 degrees Fahrenheit (123 degrees Celsius), while lunar nights also last 14 Earth days (due to the moon's rotation) and maintain a frigid cold of minus 387 degrees Fahrenheit (minus 233 degrees Celsius). 

"About the only place we could build a base that wouldn't have to deal with these extremes is, oddly enough, near the lunar poles," said Rick Elphic, project scientist for NASA's LADEE probe, which studied the moon's atmosphere and dust environment before performing a planned crash into the natural satellitein April 2014. These areas likely store vast amounts of water-ice and enjoy low levels of light from the sun for several months at a time.

"Instead of the blazing heat of lunar noon, it is a kind of perpetual balmy sunset, with temperatures around 0 degrees Celsius [32 degrees Fahrenheit] due to the low angle of the sun," Elphic added.

Vacations away from pole outposts would offer up sights unlike anything on Earth. Decorating the moon's vast lava plains are large impact-borne "mountains," the tallest of which is 3.4 miles (5.5 kilometers) high, about the size of Mount Saint Elias on the border of Alaska and Canada. "Skylight" holes puncture some of the plains where lava likely drained into sub-surface caverns — the perfect adventure for lunar spelunkers.

The moon also sports huge craters, such as the 25-mile-wide (40 km) Aristarchus crater. A view from the rim of Aristarchus would "dwarf the Grand Canyon and make Meteor Crater in Arizona look like a hole in a putting green," Elphic told Space.com via email.


Lunar athletes would not need to check the forecast, however. Because of its very tenuous atmosphere, the moon has no weather. "Every day is sunny with no chance of rain!" Elphic added. You would, however, have to look out for so-called space weather, which includes meteor particles that can be as large as golf balls and highly energetic particles from solar flares.

Another potential danger would be moonquakes. Seismometers left on the lunar surface during Apollo show that the moon is still seismically active, and even has rare, hour-long quakes measuring up to 5.5 on the Richter scale. These quakes would be strong enough to cause structural damage to buildings.

"So don't leave Earth for your home on the moon thinking you've left seismic activity behind," Elphic said. "Make sure your lunar house is up to code."

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Aliens Even More Likely Now To Be Out There ~ Average star has two potentially Earth-like worlds



Concept art depicting the lights of an ET civilisation on an exoplanet. Credit: David A Aguilar (CfA)

Excerpt from theregister.co.uk



Boffins in Australia have applied a hundreds-of-years-old astronomical rule to data from the Kepler planet-hunting space telescope. They've come to the conclusion that the average star in our galaxy has not one but two Earth-size planets in its "goldilocks" zone where liquid water - and thus, life along Earthly lines - could exist.

“The ingredients for life are plentiful, and we now know that habitable environments are plentiful,” says Professor Charley Lineweaver, a down-under astrophysicist.

Lineweaver and PhD student Tim Bovaird worked this out by reviewing the data on exoplanets discovered by the famed Kepler planet-hunter space scope. Kepler naturally tends to find exoplanets which orbit close to their parent suns, as it detects them by the changes in light they make by passing in front of the star. As a result, most Kepler exoplanets are too hot for liquid water to be present on their surfaces, which makes them comparatively boring.
Good planets in the "goldilocks" zone which is neither too hot nor too cold are much harder to detect with Kepler, which is a shame as these are the planets which might be home to alien life - or alternatively, home one day to transplanted Earth life including human colonists, once we've cracked that pesky interstellar travel problem.

However there exists a thing called the Titius-Bode relation - aka Bode's Law - which can be used, once you know where some inner planets are, to predict where ones further out will be found.

Assuming Bode's Law works for other suns as it does here, and inputting the positions of known inner exoplanets found by Kepler, Lineweaver and Bovaird found that on average a star in our galaxy has two planets in its potentially-habitable zone.

That doesn't mean there are habitable or inhabited planets at every star, of course. Even here in our solar system, apparently lifeless (and not very habitable) Mars is in the habitable zone.

Even so, there are an awful lot of planets in the galaxy, so some at least ought to have life on them, and in some cases this life ought to have achieved a detectable civilisation. Prof Lineweaver admits that the total lack of any sign of this is a bit of a puzzler.

"The universe is not teeming with aliens with human-like intelligence that can build radio telescopes and space ships," admits the prof. "Otherwise we would have seen or heard from them.
“It could be that there is some other bottleneck for the emergence of life that we haven’t worked out yet. Or intelligent civilisations evolve, but then self-destruct.”

Of course, humans - some approximations of which have been around for some hundreds of thousands of years, perhaps - have only had civilisation of any kind in any location for a few thousand of those years. Our civilisation has only risen to levels where it could be detectable across interstellar distances very recently.

There may be many planets out there inhabited by intelligent aliens who either have no civilisation at all, or only primitive civilisation. There may be quite a few who have reached or passed the stage of emitting noticeable amounts of radio or other telltale signs, but those emissions either will not reach us for hundreds of thousands of years - or went past long ago.

It would seem reasonable to suspect that there are multitudes of worlds out there where life exists in plenty but has never become intelligent, as Earth life was for millions of years before early humans began using tools really quite recently.

But the numbers are still such that the apparent absence of star-travelling aliens could make you worry about the viability of technological civilisation if, like Professor Lineweaver, you learn your astrophysics out of textbooks and lectures (and publish your research, as we see here, in hefty boffinry journals like the Monthly Notices of the Royal Astronomical Society).

But if movies, speculofictive novels and TV have taught us anything here on the Reg alien life desk, it is that in fact the galaxy is swarming with star-travelling aliens (and/or humans taken secretly from planet Earth for mysterious purposes in the past, or perhaps humans from somewhere else etc). The reason we don't know about them is that they don't want us to.

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Neptune-Like Planets Could Transfom Into Habitable Worlds

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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Gullies suggest comet Vesta once had flowing water on its surface



This image of the giant asteroid Vesta was taken by NASA's Dawn spacecraft, as part of a rotation characterization sequence on July 24, 2011


Excerpt from natmonitor.com

NASA’s Dawn spacecraft is currently approaching the dwarf planet Ceres, the largest object in the asteroid belt that lies between Mars and Jupiter. However, from 2011 to 2013 Dawn collected extensive data on Vesta, the second largest object in the asteroid belt and one of the largest known comets in our solar system.

The data collected from Vesta is still being analyzed and will continue to be for years to come. As the data is examined interesting new information about the giant asteroid is coming to light. Vesta which is very cold and has no atmosphere has long thought to be dry. A new study published in the journal Earth and Planetary Science Letters casts doubt on that assumption.
While there are certainly no rivers and lakes on Vesta, photographs taken by Dawn show evidence of short lived flows of water mobilized material on the surface.

“Nobody expected to find evidence of water on Vesta. The surface is very cold and there is no atmosphere, so any water on the surface evaporates. However, Vesta is proving to be a very interesting and complex planetary body,” said Jennifer Scully, postgraduate researcher at the University of California, Los Angeles in a statement.

The research could change some basic assumptions in planetary science.

“These results, and many others from the Dawn mission, show that Vesta is home to many processes that were previously thought to be exclusive to planets. We look forward to uncovering even more insights and mysteries when Dawn studies Ceres,” said UCLA’s Christopher Russell, principal investigator for the Dawn mission.
The curved gullies on vesta are very different from what would be expected from dry material flows, say the researchers.

“We’re not suggesting that there was a river-like flow of water. We’re suggesting a process similar to debris flows, where a small amount of water mobilizes the sandy and rocky particles into a flow. These features on Vesta share many characteristics with those formed by debris flows on Earth and Mars,“ said Scully.

The leading theory so far is that Vesta has small patches of ice beneath the surface, possibly deposited by impacts from other comets. Later impacts could have heated the ice enough to thaw some of the water, releasing it into the crater.

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The Best Bet for Alien Life May Be in Planetary Systems Very Different From Ours




Excerpt from wired.com


In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.

But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.

At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.

But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.

M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.

“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.

That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.

This illustration shows Kepler-186f, the first rocky planet found in a star's habitable zone. Its star is an M dwarf.
This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. NASA Ames/SETI Institute/JPL-Caltech


M dwarfs have another thing going for them. They’re the most common star in the galaxy, comprising an estimated 75 percent of the Milky Way’s hundreds of billions of stars. If Dressing’s estimates are right, then our galaxy could be teeming with 100 billion Earth-sized planets in their stars’ habitable zones.

To be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.

And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.

But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.

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NASA Spacecraft Begins 1st Ever Approach To Pluto





Excerpt from 
sanfrancisco.cbslocal.com

SAN FRANCISCO (CBS SF) – Man is about to reach closer to Pluto than ever before as the NASA New Horizons spacecraft begins the first of several approach phases toward the dwarf planet at the edge of our solar system.

When the mission was in the planning phases, Pluto was still considered a planet, but in 2006 it was reclassified as a dwarf planet. That same year, the New Horizons spacecraft blasted off as the fastest ever, shooting out off on a 4.6 billion mile journey to the distant sphere.


The piano-size New Horizons craft was in a hibernation phase as it traveled the first 3 billion miles toward Pluto. It woke up last month and is now getting ready for the first photo shoot.

“NASA first mission to distant Pluto will also be humankind’s first close up view of this cold, unexplored world in our solar system,” said Jim Green, director of NASA’s Planetary Science Division at the agency’s Headquarters in Washington.

Beginning January 25th, the probe will begin snapping photos of Pluto, which is the 10th largest celestial body orbiting our sun.
The later stages of approach will require steering the craft closer to Pluto by using photo information to steer around five known moons and other potential perils.

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Kepler Space Telescope Finds More Earth-like Planets ~ Learn how to join the search


 


Excerpt from
waaytv.com

NASA's Kepler Space Telescope has been hunting the cosmos for exoplanets since March of 2009.  In its nearly five years of searching the stars, it has found thousands of possible candidates.  Scientists recently verified the thousandth planet Kepler had found, and even more exciting, they announced that Kepler had found three more Earth-like planets.
Those three planets bring Kepler's Earth-like planet count to a total of eight.  In order to qualify as "Earth-like," these exoplanets must be less than twice the size of the Earth and orbit their own sun within the habitable zone.  This "Goldilocks zone" is a belt in solar systems where it's neither too hot nor too cold for liquid water to exist.

"Each result from the planet-hunting Kepler mission's treasure trove of data takes us another step closer to answering the question of whether we are alone in the Universe," said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “The Kepler team and its science community continue to produce impressive results with the data from this venerable explorer."

The Kepler team has also found super-Earths and gas giants like Jupiter around other stars.  NASA artists compiled retro-style travel posters from three discovered planets.
Kepler finds planets by watching distant stars for fluctuation in light.  If the light hitting the telescope drops dramatically and then returns to normal levels, chances are a planet came in between the star and Kepler.  Scientists can analyze the data and light filtered by the candidate planet's atmosphere to make guesses at the size, mass and composition.

"With each new discovery of these small, possibly rocky worlds, our confidence strengthens in the determination of the true frequency of planets like Earth," said co-author Doug Caldwell, SETI Institute Kepler scientist at NASA's Ames Research Center at Moffett Field, California. "The day is on the horizon when we’ll know how common temperate, rocky planets like Earth are.”

The space telescope actually has two crippled stabilizing gyros.  But instead of giving up on the mission, engineers are using pressure from photons emitted by the sun to stabilize the telescope.  The first space telescope looking for alien worlds is literally balancing on a sunbeam to continue its mission, and that's not science fiction, that's science fact.

Citizen scientists can also participate in the mission.  The website PlanetHunters.org contains catalogs of data from K1, the original Kepler mission, and K2, the extended mission making use of the sun to balance the telescope.  The K2 data has been sorted through, but Planet Hunters still needs help sifting through the K1 data.
The website's instructions read:

"As the planet passes in front of (or transits) a star, it blocks out a small amount of the star’s light, making the star appear a little bit dimmer. You’re looking for points on the light curve that appear lower than the rest. When you spot a potential transit, mark each one on the light curve."

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What to Do If You See a Pet Left Out in the Cold


Concerned neighbors rescued Barbie and her puppies from the snow. Scott Townsend

From humanesociety.org

It can be a crime to leave pets outside in extreme temperatures without food and shelter


Cold weather can be deadly for pets. As the temperature plummets in many parts of the country, The Humane Society of the United States sees a marked increase in the number of complaints about dogs and cats who have been left outside with no food or shelter.

We encourage you to contact local law enforcement agencies because pets left outside in extreme temperatures, especially without food and shelter, are at risk of hypothermia, frostbite and even death. Their owners are at risk of facing criminal charges.

The act of leaving a pet outside without food or adequate shelter often receives less attention than a violent attack against an animal, but neglect is a crime. "Especially in these cold months, it is important for people to bring their pets inside and for others to report neglected animals to law enforcement,” says Ashley Mauceri, HSUS manager for cruelty response, who fields these calls.


One of the most common forms of animal cruelty, cases of animals left outside in dangerous weather are investigated more by police and animal control agencies than any other form of animal abuse. Our most constant companions—dogs and cats—feel the effects of winter weather as much as we do, only they are often cast outside to weather the cold or a storm owing to a misconception that the fur on their backs will insulate them from suffering. Without proper shelter, food and water, these domesticated animals’ chances of survival in frigid temperatures is greatly decreased. Any pet owners who aren't sure what protections their pets need during cold weather can read our cold-weather advice for keeping pets safe.

While views on animal welfare vary from region to region, there are laws in place in every state to prevent needless suffering. Callers to The HSUS report numerous cases across the country of animals left out in the cold, but the organization is also working with an increasing number of law enforcement agencies that recognize the importance of intervention in these cases.


The facts


  • Animal neglect is considered a misdemeanor crime in all 50 states and Washington, D.C.
  • Felony penalties can be levied in Massachusetts and Oklahoma for any animal neglect case.
  • Felony charges can be applied in animal neglect resulting in death in California, Connecticut, Florida and Washington, D.C.

 How you can help


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