Why They Probably Know We Are Here, Reason #57

A recently published study provides support for the idea that an advanced technological civilization in an extrasolar planetary system would probably know the Earth exists and that it supports life.  

Scientists at the Naval Research Laboratory suggest that we can find extrasolar planets -- at least large Jupiter-class ones -- by listening with radio telescopes for the "noise" generated by their magnetic fields.  While the technology to detect Earth-sized planets using this method is currently beyond our financial reach, it is not inconceivable.

The idea is similar to one proposed in July.  

Last summer, scientists announced they had found another reason to think any advanced technological civilizations in our galactic neighborhood already know the Earth exists, as well as its basic characteristics: the Auroral Kilometric Radiation (AKR).

Like a lighthouse beacon, AKR blasts a beam of electromagnetic waves into outer space, a beam 10,000 times more powerful than any human-made radio source. Scientists first discovered the AKR in the 1970s, but now, thanks to the European Space Agency’s Cluster satellites, they now know the AKR radiates in a penetrating, narrow beam rather than a dissipating cone.

The importance of the discovery for the Extraterrestrial Hypothesis lies in part with the fact the AKR should be detectable from other extrasolar planetary systems, given sufficient technology.

We cannot yet detect AKR from planets outside our own solar system, but radio telescopes capable of doing so are now on engineers’ drawing boards. Once those radio telescopes are online, AKR will likely join the growing list of technologies available for detecting extrasolar planets and determining their characteristics, including habitability.

(To hear the AKR -- which sounds like R2D2 or, more poetically, birds chirping -- go here.)

With the right technology and know-how, an advanced technological civilization in an extrasolar planetary system would be able to deduce, at the very least, the Earth’s magnetic characteristics as well as its rotation period, both factors relevant to the Earth’s habitability.

The AKR joins several other developing technologies that would be available to an advanced extraterrestrial civilization, technologies that would enable it to detect the Earth’s presenceand determine its habitability – if not the very fact it is inhabited.

These technologies include the obvious (such as detecting Active SETI broadcasts and electromagnetic leakage from our planet) to the less obvious, such as spectroscopic analysis of our atmosphere when we pass in front of the Sun or analysis of light reflected from our clouds and oceans.

One more reason to think that if ET is out there, ET already knows we are here.

Of course, Seth Shostak wasted no time last summer throwing cold water on these predictions.

Shostak quickly pointed out Earth's AKR would be drowned by similar signals emitted by the Sun, Jupiter, and our other neighbors in our solar system. Shostak says with our current technology we could not detect an Earth-like planet's AKR in a neighboring extrasolar planetary system, although he demurs "aliens may have such sophisticated instruments."

Well, I hope they do.

As Shostak has pointed out, if we have intelligent extraterrestrial neighbors, they are likely to be far more advanced than we are technologically. However, if Shostak is correct, we probably won't have much success in the near future using phenomena like the AKR to detect the presence of Earth-like planets in other solar systems, absent a significant technological advance.

Although Earth's AKR is extraordinarily powerful, Shostak believes intentional signals will be far easier to detect due to their having a potentially more focused beam and narrower band.

Did Alien World Cause Star To Flicker?

Beta Pictoris in infrared light.  Credit:  ESO

Newly published research indicates the mysterious dimming of the star Beta Pictoris 28 years ago may have been caused by the eclipsing action of one of the star's recently discovered planets.

Back in November 2008, the European Space Organization announced that French scientists using ESO's Very Large Telescope had imaged a gas giant planet orbiting Beta Pictoris, becoming the first to photograph an extrasolar planet that orbits its host star as closely as Saturn orbits the Sun.

Now, new research to be published in Astronomy and Astrophysics indicates that variations in Beta Pictoris' apparent magnitude may have been caused by the planet transiting across the face of the star as observed from Earth -- even thought the existence of the planet was unknown at that time.  

On November 10, 1981, Beta Pictoris showed strong and rapid fluctuations in apparent brightness that were attributed at that time to the transit of a giant comet or a planet orbiting at several Astronomical Units from the star.  

Only 12 million years old, the infant star Beta Pictoris is located 70 light-years from Earth in the Constellation Pictor (the Painter).

Earth Life Origin Earlier Than Thought

Source and Credit:  Penn State

Scientists at Penn State have dug up new evidence that oxygen-producing micro-organisms originated on Earth much earlier than previously thought -- as much as 3.46 billion years ago.  This is quite early when compared to the Earth's age of 4.54 billion years, lending further support to the notion that life may be ubiquitous -- or at least commonplace -- in our Universe.

According to a Penn State press release:

Red jasper cored from layers 3.46 billion years old suggests that not only did the oceans contain abundant oxygen then, but that the atmosphere was as oxygen rich as it is today, according to geologists.

This jasper or hematite-rich chert formed in ways similar to the way this rock forms around hydrothermal vents in the deep oceans today. 

"Many people have assumed that the hematite in ancient rocks formed by the oxidation of siderite in the modern atmosphere," said Hiroshi Ohmoto, professor of geochemistry, Penn State. "That is why we wanted to drill deeper, below the water table and recover unweathered rocks."

The researchers drilled diagonally into the base of a hill in the Pilbara Craton in northwest Western Australia to obtain samples of jasper that could not have been exposed to the atmosphere or water. These jaspers could be dated to 3.46 billion years ago.

"Everyone agrees that this jasper is 3.46 billion years old," said Ohmoto. "If hematite were formed by the oxidation of siderite at any time, the hematite would be found on the outside of the siderite, but it is found inside," he reported in a recent issue of Nature Geoscience.

The next step was to determine if the hematite formed near the water's surface or in the depths. Iron compounds exposed to ultra violet light can form ferric hydroxide, which can sink to the bottom as tiny particles and then converted to hematite at temperatures of at least 140 degrees Fahrenheit.

"There are a number of cases around the world where hematite is formed in this way," says Ohmoto. "So just because there is hematite, there is not necessarily oxygen in the water or the atmosphere."

The key to determining if ultra violet light or oxygen formed the hematite is the crystalline structure of the hematite itself. If the precursors of hematite were formed at the surface, the crystalline structure of the rock would have formed from small particles aggregating producing large crystals with lots of empty spaces between. Using transmission electron microscopy, the researchers did not find that crystalline structure.

"We found that the hematite from this core was made of a single crystal and therefore was not hematite made by ultra violet radiation," said Ohmoto.

This could only happen if the deep ocean contained oxygen and the iron rich fluids came into contact at high temperatures. Ohmoto and his team believe that this specific layer of hematite formed when a plume of heated water, like those found today at hydrothermal vents, converted the iron compounds into hematite using oxygen dissolved in the deep ocean water.

"This explains why this hematite is only found in areas with active submarine volcanism," said Ohmoto. "It also means that there was oxygen in the atmosphere 3.46 billion years ago, because the only mechanism for oxygen to exist in the deep oceans is for there to be oxygen in the atmosphere."

In fact, the researchers suggest that to have sufficient oxygen at depth, there had to be as much oxygen in the atmosphere 3.46 billion years ago as there is in today's atmosphere. To have this amount of oxygen, the Earth must have had oxygen producing organisms like cyanobacteria actively producing it, placing these organisms much earlier in Earth's history than previously thought.

"Usually, we look at the remnant of what we think is biological activity to understand the Earth's biology," said Ohmoto. "Our approach is unique because we look at the mineral ferric oxide to decipher biological activity."

Ohmoto suggests that this approach eliminates the problems trying to decide if carbon residues found in sediments were biologically created or simply chemical artifacts.

FINDS Exo-Earths

The Planetary Society is teaming up with renown planet hunters Geoff Marcy and Debra Fischer on a new high-tech optical experiment that promises to pioneer a new technology that may help bag the first truly Earth-sized extrasolar planet.

Dubbed FINDS Exo-Earths -- for Fiber-optic Improved Next generation Doppler Search for Exo-Earths -- the experiment is a new high-end optical system to be installed on the 3-meter telescope at Lick Observatory in California.  The experiment could play a crucial role in confirming possible discoveries of the exoplanet-hunting Kepler mission launched earlier this month.

FINDS Exo-Earths works by fine-tuning telescopic optics using fiber optics to bring Earth-sized terrestrial exoplanets within the grasp of the well-established radial velocity method of extrasolar planet detection, which to date has been generally limited to finding massive "hot Jupiters" that orbit extremely close to their host stars.

Once the technology is tested at the Lick observatory, Marcy and Fischer plan to deploy it on the much larger 10-meter Keck telescope in Hawaii, finally bringing Earth-sized planet within reach of the radial velocity method.

Hello, HAL

The age of artificial intelligence edges closer.

Via Slashdot:

European researchers have taken a step towards replicating the functioning of the brain in silicon, creating new custom chip with the equivalent of 200,000 neurons linked up by 50 million synaptic connections. The aim of the Fast Analog Computing with Emergent Transient States (FACETS) project is to better understand how to construct massively parallel computer systems modeled on a biological brain. Unlike IBM's Blue Brain project, which involves modeling a brain in software, this approach makes it much easier to create a truly parallel computing system. The set-up also features a distributed algorithm that introduces an element of plasticity, allowing the circuit to learn and adapt. The researchers plan to connect thousands of chips to create a circuit with a billion neurons and 10^13 synapses (about a tenth of the complexity of the human brain).

The Variety of Exoplanets

Source and Credit:  PlanetQuest (JPL/NASA)

In order to find habitable planets orbiting other stars, it's helpful for scientists to be able to understand how planets like ours are created. Sean Raymond of the University of Colorado and his team are not only finding clues to how this mysterious process works, they're also discovering evidence that Earthlike planets may be much more common than was originally thought.

Raymond's area of expertise is in creating computer models of how terrestrial planets form from the disks of gas and dust that surround young stars. "We can simulate the orbits of small bodies in disks around young stars, and the collisions of those small bodies that cause them to grow and eventually become planets," he says. "It's quite fun -- kind of like getting to play God." Collaborating with him on this groundbreaking research are Avi Mandell of NASA's Goddard Space Flight Center, Tom Quinn of the University of Washington, Jonathan Lunine of the University of Arizona, and Steinn Sigurdsson of Penn State.

According to Raymond, the properties of a star's disk are the ingredients that determine what kind of planetary system will form. "The most important factor is what the disk looks like. That tells you how material is distributed and what planets you're going to get," he says.

The first planets to arise are typically gas giants, like Jupiter and Saturn in our own solar system. "These planets take about two million years to form -- much faster than the Earth, which took about one-hundred million years," Raymond says. We know that they come together so quickly, he says, because planet-forming disks around other stars lose their gas in that time. The predominant theory is that gas giants form "bottom-up" -- the gravity of their rocky cores quickly attracts a thick blanket of gas from the debris disk.

The small, rocky planets, like Earth and Venus, form from rocks and dust that collide and clump together closer to the star. Raymond points out that the asteroid belt in our own solar system is probably a remainder of the material that helped create Earth and the other inner planets.

Once the rocky core of an Earth-like planet starts to come together, it's time to add water. It is commonly thought that icy comets smashing into the Earth brought the water that today fills our lakes and oceans, but Raymond says that this isn't likely to have been the case. "Comets are really small and have very elongated orbits with very small collision probabilities with Earth," explains Raymond. "What probably happened is that icy asteroids collided with the Earth and brought the water."

Raymond's team has also found that gas giant planets, like Jupiter in our own solar system, can have a powerful effect of the formation of Earth-like planets. "If Jupiter's orbit around the sun was just a bit more eccentric (oblong), it would have scattered a lot of the material that delivered water to the Earth, kicking it out of the solar system instead," he says. "The result would have been an Earth that had only 10 percent of the water it does now."

But perhaps most surprising are Raymond's simulations concerning solar systems with "hot Jupiters," gas giant planets that form far away from their stars, then spiral inward, often to scorchingly close orbits.

Scientists initially figured that the presence of these planets indicated a barren solar system, with no chance of harboring life. Any young Earth-like planet, they thought, would be obliterated by the gas giant as it marched inwards. "They migrate right through where terrestrial planets would be forming," Raymond says. "When we tried simulating the formation of Earths in these systems, we didn't think it would work."

Instead, Raymond's team found that hot Jupiters help create a "second generation" of terrestrial planets. As they migrate inward, gas giants corral some disk material closer to the star, and scatter the rest of it outwards. The material closer to the star, Raymond explains, forms hot Super-Earths, sweltering planets just a few times bigger than our own.

The rocky material that gets tossed outward, on the other hand, "can settle down into stable orbits and come together to create a new set of terrestrial planets. In our models, these planets have lots of water -- up to 50 times more than what's on the Earth," says Raymond. "They'd be covered in oceans." Once thought to be the sign of a dead solar system, the presence of hot Jupiters may instead indicate the presence of exotic water worlds.

Raymond's research will go a long way to helping planet hunters "narrow down the field" as they pick which extrasolar systems might be good candidates for harboring an Earth-like planet. These planets might be good targets for follow-up study by future planet-finders, like NASA's planned SIM Lite mission.

It's also a sign that Earth-like planets elsewhere in the galaxy may be anything but rare. "One third of the exoplanet systems we've found are pretty good candidates for a terrestrial planet," Raymond says. "There might be Earths all over the place...we just have to wait and see."

Alien Life Discovered By Indian Scientists?

A press release from the Indian Space Research Organisation or ISRO suggests that its scientists believe three new species of micro-organisms discovered in the upper stratosphere may be of extraterrestrial origin, in part because they appear unrelated to any known terrestrial life and are immune to the deadly effects of ultraviolet radiation found in the upper atmosphere.

Quoting the press release, "While the present study does not conclusively establish the extra-terrestrial origin of microorganisms, it does provide positive encouragement to continue the work in our quest to explore the origin of life."

Here's the text of the full press release:

"Three new species of bacteria, which are not found on Earth and which are highly resistant to ultra-violet radiation, have been discovered in the upper stratosphere by Indian scientists. One of the new species has been named as Janibacter hoylei, after the Distinguished Astrophysicist Fred Hoyle, the second as Bacillus isronensis recognising the contribution of ISRO in the balloon experiments which led to its discovery and the third as Bacillus aryabhata after India’s celebrated ancient astronomer Aryabhata and also the first satellite of ISRO.

The experiment was conducted using a 26.7 million cubic feet balloon carrying a 459 kg scientific payload soaked in 38 kg of liquid Neon, which was flown from the National Balloon Facility in Hyderabad, operated by the Tata Institute of Fundamental Research (TIFR). The payload consisted of a cryosampler containing sixteen evacuated and sterilised stainless steel probes. Throughout the flight, the probes remained immersed in liquid Neon to create a cryopump effect. These cylinders, after collecting air samples from different heights ranging from 20 km to 41 km, were parachuted down and safely retrieved. These samples were analysed by scientists at the Center for Cellular and Molecular Biology, Hyderabad as well as the National Center for Cell Science (NCCS), Pune for independent examination, ensuring that both laboratories followed similar protocols to achieve homogeneity of procedure and interpretation.

The Analytical Findings are Summarised as Follows:

In all, 12 bacterial and six fungal colonies were detected, nine of which, based on 16S RNA gene sequence, showed greater than 98% similarity with reported known species on earth. Three bacterial colonies, namely, PVAS-1, B3 W22 and B8 W22 were, however, totally new species. All the three newly identified species had significantly higher UV resistance compared to their nearest phylogenetic neighbours. Of the above, PVAS-1, identified as a member of the genus Janibacter, has been named Janibacter hoylei. sp. nov. The second new species B3 W22 was named as Bacillus isronensis sp.nov. and the third new species B8 W22 as Bacillus aryabhata.

The precautionary measures and controls operating in this experiment inspire confidence that these species were picked up in the stratosphere. While the present study does not conclusively establish the extra-terrestrial origin of microorganisms, it does provide positive encouragement to continue the work in our quest to explore the origin of life.

This multi-institutional effort had Jayant Narlikar from the Inter-University Centre for Astronomy and Astrophysics, Pune as Principal Investigator and veteran Scientists U.R. Rao from ISRO and P.M. Bhargava from Anveshna supported as mentors of the experiment. S. Shivaji from CCMB and Yogesh Shouche from NCCS were the biology experts and Ravi Manchanda from TIFR was in charge of the balloon facility. C.B.S. Dutt was the Project Director from ISRO who was in charge of preparing and operating the complex payload.

This was the second such experiment conducted by ISRO, the first one being in 2001. Even though the first experiment had yielded positive results, it was decided to repeat the experiment by exercising extra care to ensure that it was totally free from any terrestrial contamination."

Meet Cybernetic Human HRP-4C

Read more here at USA Today and BBC.com.

Arm All Phasers!

Wired.com reports on developing technology that may lead to military weapons capable of destroying missiles in flight using accelerated "magnetoplasmoids" travelling 200 kilometers a second.

The developer calls the technology "Phased Hyper-Acceleration for Shock, EMP, and Radiation" -- PHASER for short.

Seriously.

Deep Time

This video, produced by Claire Evans at SEED Magazine, condenses 4.6 billion years of history – since the birth of our Sun and the formation of our solar system -- into a single minute, offering a unique perspective.

Air-Breathing Rocket Planes

Both New Scientist and Space.com have stories on an air-breathing rocket engine under development in Britain that could usher in the era of the commercially viable and reusable space plane.

The European Space Agency and British government have awarded $1.28 million dollars to Reaction Engines Limited to help develop an air-breathing rocket engine for the Skylon space plane. The reusable space plane would take off from an airstrip, deliver cargo into orbit and return to the same runway.

Did Earth Life Come From Ceres?

Source and Credit:  Astrobiology Magazine

Astrobiologists hope to find life elsewhere in the universe, or possibly even in our own cosmic neighborhood, the solar system. Their efforts are usually concentrated on worlds such as the planet Mars, or icy moons like Europa. However, there are other, less conventional locations in the solar system where scientists think life may be found.

Ceres: an unusual choice

At the International Society for the Study of the Origin of Life conference in Florence, Italy, Joop Houtkooper from the University of Giessen divulged a theory that life could have originated on an object in the asteroid belt named Ceres. Ceres was considered to be a planet when it was discovered in 1801, but it was later downgraded to asteroid status. With the latest planet definition from the International Astronomical Union, the round object is now considered a dwarf planet. Is there a chance that this exotic world is home to extraterrestrial organisms?

“This idea came to me when I heard a talk about all the satellites in the solar system that consist of a large part of ice, much of which is probably still in a liquid state,” says Houtkooper. “The total volume of all this water is something like 40 times greater than all the oceans on Earth.”

This reminded Houtkooper of a theory about how life originated. Organisms may have first developed around hydrothermal vents, which lie at the bottom of oceans and spew hot chemicals. Many icy bodies in our solar system have rocky cores, so they may have had or still have hydrothermal vents. Houtkooper realized, “if life is not unique to the Earth and could exist elsewhere, then these icy bodies are the places where life may have originated.”

Read the full article here.