The Cutting Edge
Some of the leading edge topics in Science.
Are they all sensible? You decide.
Serious and Unanswered Questions
4-18-16 Ten questions still baffling scientists
10 questions still baffling scientists
Why do people spontaneously combust? Can animals predict earthquakes? And other puzzlers. Why do we yawn?, Why do people spontaneously combust?, Why do placebos work?, What was life's last universal common ancestor?, How does memory work?, Can animals really predict earthquakes?, How do organs know when to stop growing?, Are there human pheromones?, What's the deal with gravity?, How many species are there?
Dark Matter (or not)
8-24-15 What is our Universe made of?
What is our Universe made of?
We only know about a small fraction of the matter in the Universe. The rest is a mysterious substance known only as dark matter. (Webmaster's comment: An excellent explanation of the "Dark Matter Problem." We think it's there because of its effects on galaxies, but we have no idea what it's made of or how to detect it other than by those effects. It seems to make up most of the universe while the stuff we see makes up only a small percentage. Read this entire article and you'll be as knowledgeable about dark matter as anyone.)
Alien Life (or not)
4-23-16 How alien can a planet be and still support life?
How alien can a planet be and still support life?
Geoscientists imagine the unearthly mechanisms that could keep alien planets habitable. Earth scientists reimagine the Goldilocks zone and what makes a planet habitable. The hunt for extraterrestrial life has long focused on planets at a just-right distance from alien stars, where liquid water can exist on a planet’s surface. Just how fantastical a planet can be and still support recognizable life isn’t just a question for science fiction. Astronomers are searching the stars for otherworldly inhabitants, and they need a road map. Which planets are most likely to harbor life? That’s where geoscientists’ imaginations come in. Applying their knowledge of how our world works and what allows life to flourish, they are envisioning what kind of other planetary configurations could sustain thriving biospheres. You don’t necessarily need an Earth-like planet to support Earth-like life, new research suggests. For decades, thinking about the best way to search for extraterrestrials has centered on a “Goldilocks” zone where temperatures are “just right” for liquid water, a key ingredient for life, to wet the surface of an Earth doppelgänger. But now it’s time to think outside the Goldilocks zone, some scientists say. Unearthly mechanisms could keep greenhouse gas levels in check and warm planets in the coldest outer reaches of a solar system. Life itself could even play a starring role in a planet’s enduring habitability.
4-19-16 New telescopes will search for signs of life on distant planets
New telescopes will search for signs of life on distant planets
Atmosphere of a world in another solar system might reveal hints of alien biological activity. A suite of current and future telescopes (Spitzer, TESS, Hubble, James Webb and WFIRST-AFTA) could identify remote habitable worlds and peer into the newfound atmospheres for hints of alien biology. Our galaxy is teeming with planets. Over the last 25 years, astronomers have cataloged about 2,000 worlds in 1,300 systems scattered around our stellar neighborhood. While most of these exoplanets look nothing like Earth (and in some cases, like nothing that orbits our sun), the bonanza of alien worlds implies a tantalizing possibility: There is a lot of real estate out there suitable for life. On Earth, life alters the atmosphere. If plants and critters weren’t around to keep churning out oxygen and methane, those gases would quickly vanish. Water, carbon dioxide, methane, oxygen and ozone are examples of “biosignatures,” key markers of a planet crawling with life as we know it. Setting aside questions about how recognizable alien life might be, detecting biosignatures in the atmosphere of an exoplanet would give astronomers the first strong clue that we are not alone.
4-18-16 Will we know extraterrestrial life when we see it?
Will we know extraterrestrial life when we see it?
Recognizing life on other worlds requires wiggle room in the definition of what it means to be alive. A Martian microbe, envisioned by planetary geologist Kathie Thomas-Keprta, would need a tough outer wall to withstand the elements and magnetic crystals to help it navigate. But recognizing life on different worlds isn’t likely to be this simple, especially if the recipe for life elsewhere doesn’t use familiar ingredients. There may even be things alive on Earth that have been overlooked because they don’t fit standard definitions of life, some scientists suspect. Astrobiologists need some ground rules — with some built-in wiggle room — for when they can confidently declare, “It’s alive!”
4-15-16 A new strategy for hunting aliens
A new strategy for hunting aliens
For 50 years, astronomers looking for signs of alien life have zeroed in on Earth-like planets that orbit large sun-like stars. But now a team from the Search for Extraterrestrial Intelligence (SETI) is taking a novel approach: focusing on red dwarfs, the dimmest and oldest stars in the galaxy. Over the next two years, SETI will turn a group of 42 radio antennae in California toward 20,000 of these relatively small, cold stars, listening for radio signals that could reveal the existence of life. Red dwarfs have been largely discounted by alien-hunters, who assumed that planets orbiting them would not have the right conditions to support life. Any planets in a red dwarf’s “habitable zone,” the region where temperatures are right to sustain water, would likely be so close to the star that they would be “tidally locked.” That means half the planet would constantly face the star, rendering it scorching hot, while the other half remained perpetually dark and frozen. But if a planet orbiting a red dwarf has oceans and an atmosphere, new research suggests, heat from the star could be more evenly distributed. Since red stars been around for billions of years longer than other stars, astronomers say that life on their planets is more likely to have had enough time to evolve into intelligent species. As SETI’s Seth Shostak tells The Washington Post, “this may be one case where being older may actually be better.”
4-12-16 Billionaire pledges $100m to send spaceship
Billionaire pledges $100m to send spaceship
Yuri Milner has backed a plan to research sending tiny, laser-powered spacecraft to the nearest star at 20 per cent of the speed of light. Today, billionaire Yuri Milner, along with physicist Stephen Hawking, announced the largest ever investment in interstellar travel: a $100 million fund to research and prototype a spacecraft capable of reaching the nearest star in just 20 years. Forget starships, though. These “wafersats” would be small enough to fit in your hand, weighing just a few grams. Milner and his scientific advisory team believe recent developments in lasers and nanotechnology should make it possible to send thousands of these probes to Alpha Centauri, where they could beam back pictures and scientific data on any planets in orbit. The plan involves launching spacecraft that are little more than a silicon wafer 10 centimetres across, comparable to the guts of a smartphone. These probes will use metre-wide lightsails of reflective material to capture the momentum from colliding photons and propel themselves along. Sails powered by sunlight are in the works, but these only produce a small amount of thrust. That’s why, back on Earth, a 100 gigawatt laser will shoot into the sky and dump enormous amounts of energy into this sail, accelerating the craft to 20 per cent of light speed – enough to coast the 4 light years to Alpha Centauri in 20 years. (Webmaster's comment: The super-rich have found another way to waste their fortune. Rather than helping people solve real proplems like global warming and global ignorance, they go on ego trips costing 100 million. If it even works half the people now alive will be dead before we hear back from this space junk.)
4-12-16 Hawking backs interstellar travel project
Hawking backs interstellar travel project
Stephen Hawking is backing a project to send tiny spacecraft to another star system within a generation. They would travel trillions of miles; far further than any previous craft. A $100m (£70m) research programme to develop the computer chip-sized "starships" was launched by the billionaire Yuri Milner, supported by Facebook founder Mark Zuckerberg. The concept is to reduce the size of the spacecraft to about the size of a chip used in electronic devices. The idea is to launch a thousand of these mini-spacecraft into the Earth's orbit. Each would have a solar sail. This is like a sail on a boat - but it is pushed along by light rather than the wind. A giant laser on Earth would give each one a powerful push, sending them on their way to reaching 20% of the speed of light.
2-5-16 Why aliens aren’t saying hello
Why aliens aren’t saying hello
For decades, astronomers have searched in vain for signals from extraterrestrial life, and now planetary scientists in Australia suggest there’s a good reason why aliens are so hard to find: They didn’t last long enough to develop intelligence. Most theoretically inhabitable planets have unstable environments, the researchers say; like Mars and Venus, planets can have an early temperate period but then be transformed into frozen wastelands with thin atmospheres or blistering worlds with boiling oceans. The microbial life that arises on these worlds almost always becomes extinct. “The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens,” author Aditya Chopra, an astrobiologist at Australian National University, tells CBSNews.com. “But early life is fragile, so we believe it rarely evolves quickly enough to survive.” Since intelligent life appears to require billions of years of evolution on a planet with an unusually stable environment, he theorizes, it may be extremely rare—and perhaps even unique to Earth.
1-11-16 Famous Wow! signal might have been from comets, not aliens
Famous Wow! signal might have been from comets, not aliens
A powerful radio signal from space has puzzled astronomers for decades and led to talk of alien signals, but now there might be a more mundane explanation. On 15 August 1977, radio astronomers using the Big Ear radio telescope at Ohio State University picked up a powerful signal from space. Some believe it was our first interception of an alien broadcast. Now it seems something closer to home may have been the source: a pair of passing comets. But in the 40 years since, we’ve never heard anything like it again. Analysis of the signal ruled out a satellite, and a reflected signal from the Earth’s surface is unlikely because regulations forbid transmission in that frequency range. Antonio Paris, a professor of astronomy at St Petersburg College in Florida, thinks the signal might have come from one or more passing comets. Tracing the comets’ positions back in time, Paris says that the possible origin for the Wow! signal falls right between where they would have been.
8-17-15 What makes a planet habitable?
What makes a planet habitable?
Water in liquid form is thought to be a necessity for life on Earth. Scientists are looking for more rocky worlds that could possibly retain liquid water on their surface. Clouds' reflective qualities cool the planet and mean the habitable zone can be closer to a star. (Webmaster's comment: There is absolutely no reason life must start and evolve the way it did and has on earth. If a "something" survives and reproduces itself over time that is enough for it to be life. It may not need water, sunlight, genes or DNA. It need never have a brain or the resultant thing we call "mind.")
8-12-15 Nuclear apocalypse or nanotech invasions could reveal alien life
Nuclear apocalypse or nanotech invasions could reveal alien life
Instead of seeking living aliens, ET hunters suggest looking for alien civilizations that have wiped themselves out through technology. There are billions of potentially habitable planets out there, so why haven’t we seen signs of life beyond the solar system? Perhaps because the aliens have all destroyed themselves. A new analysis of various apocalyptic scenarios suggests that we may be able to detect distant worlds where life has been wiped out by nuclear war or nanotechnology run amok. The disparity between the vast potential for alien life and our lack of extraterrestrial contact is known as the Fermi paradox, after physicist Enrico Fermi, who asked why we appeared to be alone. It might be that microbes evolve on many worlds, but intelligent life is rare, or that most civilizations choose not to communicate and even actively hide from the rest of the universe. A third possibility is that civilizations don’t stick around very long – blink, and you’ll miss them, at least on galactic timescales. “If that’s correct, there should be some signs of dead alien civilizations all over the place,” says Duncan Forgan of the University of St Andrews, UK. (Webmaster's comment: Let's get real. It's blink and you miss them. If intelligent life is like us, super competitive and live at the expensive of all other life and all of a planet's resources, then civilizations lasting 10,000 years seem highly unlikely. They burn out their planet, and maybe one or two more in their solar system, and then go extinct. And 10,000 years in the 13,200,000,000 year time span of our galaxy means intelligent civilizations come and go in a blink.)
8-12-15 Sniff out alien life with giant library of weird chemicals
Sniff out alien life with giant library of weird chemicals
The search for vital signs of life in the atmospheres of other planets has taken a new turn with a vast library of biosignatures that could help us detect ET. Seager and her colleagues are building a cache of biosignatures – chemicals that would suggest an alien planet is playing host to life. Seager is casting her net as wide as possible. Because we can’t predict what the biochemistry and ecology of alien planets will be like, she’s looking at all small molecules, not just the ones linked to life as we know it. “Is there any limit to what sort of gas life can produce?” asks biochemist William Bains at the University of Cambridge. “Conceptually, the answer is no.”
7-31-15 Giant old galaxies, not Milky Ways, are best for life to thrive
Giant old galaxies, not Milky Ways, are best for life to thrive
Looking at how quickly stars form can nail down the galaxies that should be best for life – and our own doesn't come out on top. The cosmos may have good and bad neighborhoods. Life is most likely to evolve in giant elliptical galaxies whereas dwarf galaxies are thought to be the least hospitable – with the spiral Milky Way falling somewhere in between. The idea that the universe might have more and less hospitable regions is speculative, especially since we have yet to find any instances of alien life. But “habitable zones” – where water should be stable and Earth-like creatures have a fighting chance of surviving – have been proposed for alien solar systems and regions within galaxies. (Webmaster's comment: Alien Life "must be there somewhere" supporters are getting desperate. Having not found any evidence of intelligent life in our galaxy - the Milky Way - so far, they want to speculate about other galaxies. Other galaxies are many millions of light years away. Radio signal strength from those galaxies would have to be stronger than an exploding sun to reach us. We would be wasting our time and money looking for intelligent signals from them. It would take us 9 years just to talk back and forth to our closest star and we already know there is no intelligent life there. Trying to talk to someone millions of light years away is NUTS! What are we to do, blow up our sun to send a message? Get a life guys.)
7-20-15 Prof Stephen Hawking backs venture to listen for aliens
Prof Stephen Hawking backs venture to listen for aliens
Prof Stephen Hawking has launched a new effort to answer the question of whether there is life elsewhere in space. Speaking at the launch, Prof Hawking said: "Somewhere in the cosmos, perhaps, intelligent life may be watching these lights of ours, aware of what they mean. Or do our lights wander a lifeless cosmos - unseen beacons, announcing that here, on one rock, the Universe discovered its existence. Either way, there is no bigger question. It's time to commit to finding the answer - to search for life beyond Earth. We are alive. We are intelligent. We must know." Those behind the initiative claim it to be the biggest scientific search ever undertaken for signs of intelligent life beyond Earth. They plan to cover 10 times more of the sky than previous programmes and scan five times more of the radio spectrum, 100 times faster. (Webmaster's comment: Our best telescopes couldn't even get a clear picture of Pluto yet it is only 1/20,000 of a light year away. It's just a blurry white and gray object about one inch in diameter. How would we expect intelligent life 100 light years away to see our lights of 100 years ago? We wouldn't be able to see the lights of 1915 New York City on Pluto with our best telescopes, even today.)
7-20-15 $100m project uses world’s best radio telescopes to find aliens
$100m project uses world’s best radio telescopes to find aliens
A Russian billionaire has teamed up with a host of famous names, including Stephen Hawking, to listen for aliens in the million nearest star systems. Breakthrough Listen will look for signals that could be alien-made, whether they are messages deliberately sent into space or the alien equivalent of leaked TV broadcasts. Breakthrough Listen will focus on the million nearest star systems, the core and plane of the Milky Way, and the hundred nearest galaxies. The search will be 100 to 1000 times more efficient than ever tried before. The funding buys the team time on two of the world’s largest radio telescopes. They will scan frequency ranges between 500 MHz and 15 GHz, roughly five times wider than previous searches. More computing power will also be thrown at analysing the data, which will allow the team to look for a signal across a wide range of frequencies simultaneously. The radio telescopes will also give greater sensitivity. If there are aircraft radars somewhere in the next few hundred stars we could pick that up. (Webmaster's comment: And suppose we find a signal from a star system 100 light years away. And we send them a signal and, assuming they are even listening, they send one back. Two hundred years from now we get an answer. What then? Our great-great-grandchildren invite them to visit or ask if we can visit them? 2,000 years from now they get here or we get there. We won't care. We will be long dead. And so will be at least 20 generations of human beings.)
Let's Get Real!
About one million star systems are within 400 light-years of earth. Earth has been sending out various electromagnetic signals strong enough to be heard by an advanced civilization at our technological level for about 80 years. That means if they sent a signal back 40 years ago we should be receiving it now. So far nothing. If an advanced civilization at our technological level 400 light-years or less away has been sending out electromagnetic signals strong enough to be heard by us we should also have heard them. But again nothing.
One million star systems is about 0.0004 percent of the star systems in the milky way which has about 250 BILLION star systems. There are about 125 million star systems within 2000 light-years of Earth (about 0.05 percent of the Milky Way). Searching one million star systems every 10 years it will take us 1,250 years to search those systems for advanced civilizations with electromagnetic signals strong enough to be heard. Unless we find a signal in the next 20-30 years we may want to invest our money in something else, like saving our planet from global warming, or in making nuclear fusion work. Those would seem to be much more useful investments.
Especially since communications with any other star system can only occur at the speed of light. If the other advanced civilization is only 50 light-years away we could send a signal when you are born and maybe get an answer before you die. If it is 100 light years away your great-great-great-great-grand-children would get the answer some 200 years later. Seems like it won't make sense to be asking for visits. The Milky way is 100,000 light-years across, and we up to 80,000 light-years away from any star system in it. The human race has been civilized for the last 10,000 years or so, but much less so been sending out electromagnetic signals. Space is so HUGE and our time slice is so small.
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The Cutting Edge
Some of the leading edge topics in Science.
Are they all sensible? You decide.