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  • richardmitnick 7:33 pm on March 3, 2015 Permalink | Reply
    Tags: , Exoplanets, , Frank Drake, ,   

    From Space.com: “The Father of SETI: Q&A with Astronomer Frank Drake” 

    space-dot-com logo

    SPACE.com

    February 26, 2015
    Leonard David

    Arecibo Observatory

    Detecting signals from intelligent aliens is a lifelong quest of noted astronomer Frank Drake. He conducted the first modern search for extraterrestrial intelligence (SETI) experiment in 1960. More than five decades later, the hunt remains front-and-center for the scientist.

    5
    Frank Drake

    Drake also devised a thought experiment in 1961 to identify specific factors believed to play a role in the development of civilizations in our galaxy. This experiment took the form of an equation that researchers have used to estimate the possible number of alien civilizations — the famous Drake Equation.

    The Drake equation is:

    N = R*. fp. ne. fl. fi. fc. L

    where:

    N = the number of civilizations in our galaxy with which radio-communication might be possible (i.e. which are on our current past light cone);

    and

    R* = the average rate of star formation in our galaxy
    fp = the fraction of those stars that have planets
    ne = the average number of planets that can potentially support life per star that has planets
    fl = the fraction of planets that could support life that actually develop life at some point
    fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)
    fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
    L = the length of time for which such civilizations release detectable signals into space

    Drake constructed the “Arecibo Message” of 1974 — the first interstellar message transmitted via radio waves from Earth for the benefit of any extraterrestrial civilization that may be listening.

    The message consists of seven parts that encode the following (from the top down):[4]

    The numbers one (1) to ten (10)
    The atomic numbers of the elements hydrogen, carbon, nitrogen, oxygen, and phosphorus, which make up deoxyribonucleic acid (DNA)
    The formulas for the sugars and bases in the nucleotides of DNA
    The number of nucleotides in DNA, and a graphic of the double helix structure of DNA
    A graphic figure of a human, the dimension (physical height) of an average man, and the human population of Earth
    A graphic of the Solar System indicating which of the planets the message is coming from
    A graphic of the Arecibo radio telescope and the dimension (the physical diameter) of the transmitting antenna dish

    3
    This is the message with color added to highlight its separate parts. The actual binary transmission carried no color information.

    Space.com caught up with Drake to discuss the current state of SETI during an exclusive interview at the NASA Innovative Advanced Concepts (NIAC) 2015 symposium, which was held here from Jan. 27 to Jan. 29.

    Drake serves on the NASA NIAC External Council and is chairman emeritus of the SETI Institute in Mountain View, Calif. and director of the Carl Sagan Center for the Study of Life in the Universe.

    Space.com: What’s your view today concerning the status of SETI?

    Frank Drake: The situation with SETI is not good. The enterprise is falling apart for lack of funding. While NASA talks about “Are we alone?” as a number one question, they are putting zero money into searching for intelligent life. There’s a big disconnect there.

    We’re on the precipice. The other thing is that there are actually negative events on the horizon that are being considered.

    Space.com: And those are?

    Drake: There are two instruments, really the powerful ones for answering the “are we alone” question … the Arecibo telescope[above] and the Green Bank Telescope [GBT].

    NRAO GBT
    GBT

    They are the world’s two largest radio telescopes, and both of them are in jeopardy. There are movements afoot to close them down … dismantle them. They are both under the National Science Foundation and they are desperate to cut down the amount of money they are putting into them. And their choice is to just shut them down or to find some arrangement where somebody else steps in and provides funding.

    So this is the worst moment for SETI. And if they really pull the rug out from under the Green Bank Telescope and Arecibo … it’s suicide.

    Space.com: What happens if they close those down?

    Drake: We’re all then sitting in our living rooms and watching science fiction movies.

    Space.com: How about the international scene?

    Drake: The international scene has gone down too because all the relevant countries are cash-strapped also.

    There is a major effort in China, a 500-meter [1,640 feet] aperture spherical radio telescope. The entire reflector is under computer control with actuators. They change the shape of the reflector depending on what direction they are trying to look. The technology is very complicated and challenging. The Russians tried it and it never worked right. But … there are serious resources there.

    Space.com: Why isn’t SETI lively and bouncing along fine given all the detections?

    Drake: You would think. All those planetary detections are the greatest motivator to do SETI that we ever had. But it hasn’t had any impact, at least yet.

    Space.com: How do you reconcile the fact that exoplanet discoveries are on the upswing, yet mum’s the word from ET?

    Drake: People say that all the time … saying that you’ve been searching for years and now you’ve searched thousands of stars and found nothing. Why don’t you just give up … isn’t that the sensible thing?

    There’s a good answer to all that. Use the well-know equation and put in the parameters as we know them. A reasonable lifetime of civilizations is like 10,000 years, which is actually much more than we can justify with our own experience. It works out one in every 10 million stars will have a detectable signal. That’s the actual number. That means, to have a good chance to succeed, you have to look at a million stars at least — and not for 10 minutes — for at least days because the signal may vary in intensity. We haven’t come close to doing that. We just haven’t searched enough.

    Space.com: What are we learning about habitable zones?

    Drake: Actually the case is very much stronger for a huge abundance of life. The story seems to be that almost every star has a planetary system … and also the definition of “habitable zone” has expanded. In our system, it used to be that only Mars and Earth were potentially habitable. Now we’ve got an ocean on Europa … Titan.

    The habitable zone goes out. A habitable zone is not governed just by how far you are from the star, but what your atmosphere is. If you’ve got a lot of atmosphere, you’ve got a greenhouse effect. And that means the planet can be much farther out and be habitable.

    6
    “Radio waving” to extraterrestrials. Outward bound broadcasting from Earth has announced humanity’s technological status to other starfolk, if they are out there listening.
    Credit: Abstruse Goose

    Space.com: What is your view on the debate regarding active SETI — purposely broadcasting signals to extraterrestrials?

    Drake: There is controversy. I’m very against sending, by the way. I think it’s crazy because we’re sending all the time. We have a huge leak rate. It has been going on for years. There is benefit in eavesdropping, and you would have learned everything you can learn through successful SETI searches. There’s all kinds of reasons why sending makes no sense.

    7
    Frank Drake, center, with his colleagues, Optical SETI (OSETI) Principal Investigator Shelley Wright and Rem Stone with the 40-inch Nickel telescope at Lick Observatory in California. Outfitted with the OSETI instrument, the silver rectangular instrument package protrudes from the bottom of the telescope, plus computers, etc.
    Credit: Laurie Hatch Photography

    That reminds me of something else. We have learned, in fact, that gravitational lensing works. If they [aliens] use their star as a gravitational lens, they get this free, gigantic, super-Arecibo free of charge. They are not only picking up our radio signals, but they have been seeing the bonfires of the ancient Egyptians. They can probably tell us more about ourselves than we know … they’ve been watching all these years.

    Space.com: Can you discuss the new optical SETI efforts that you are involved with? You want to search for very brief bursts of optical light possibly sent our way by an extraterrestrial civilization to indicate their presence to us.

    Drake: It’s alive and well. We’ve gotten a couple of people who are actually giving major gifts. There’s no funding problem. There is a new instrument that has been built, and it’s going to be installed at the Lick Observatory [in California] in early March.

    The whole thing is designed to look for laser flashes. The assumption is — and this is where it gets to be tenuous — the extraterrestrials are doing us a favor. It does depend on extraterrestrials helping you by targeting you. These stellar beams are so narrow that you’ve got to know the geometry of the solar system that you’re pointing it at. They want to communicate. They have to be intent on an intentional signal specifically aimed at us. That’s a big order. So there are required actions on the part of the extraterrestrials for this to work. The big plus is that it’s cheap and relatively easy to do.

    See the full article here.

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  • richardmitnick 9:39 am on February 17, 2015 Permalink | Reply
    Tags: , , , , Exoplanets   

    From AAAS: “‘Shadow biosphere’ might be hiding strange life right under our noses” 

    AAAS

    AAAS

    14 February 2015
    Emily Conover

    1
    Scientists have found life on Earth in extreme environments like this Yellowstone hot spring, but alien life might be more elusive.

    If we came across alien life, would we even know it was alive? That was a central question posed at a session here yesterday at the annual meeting of AAAS (which publishes Science). All known life on Earth fits a particular mold, but life from other planets might break free from that mold, making it difficult for us to identify. We could even be oblivious to unfamiliar forms of life right under our noses.

    All life as we know it follows a standard protocol, known as the “central dogma,” using DNA and RNA to store genetic information, and translating that into proteins. And all living things rely on the same handful of chemical elements. So, when searching for life in remote or extreme environments scientists typically look for signs of the kind of life we’re familiar with. But, “if we have other organisms out there that do things just slightly differently, we might miss the boat,” geobiologist Victoria Orphan of the California Institute of Technology in Pasadena told attendees.

    Biologists have proposed the existence of a “shadow biosphere”—an undiscovered group of living things with biochemistry different from what we’re used to. Most of life’s diversity on our planet is too small to see, making microbes the most likely place to look for these new types of life. Already, new discoveries are shaking our beliefs about what life is. Recently discovered giant, amoeba-infecting viruses blur the line between life and nonlife—although they rely on their hosts for essential biological functions, the bacteria-sized viruses have complex genomes. Such unexpected discoveries suggest that we shouldn’t define what we are searching for by what we know is already out there, Orphan said.

    But it’s hard to search for something if you don’t know what it is. One general hallmark to look for, said planetary scientist Carolyn Porco of the Space Science Institute in Boulder, Colorado, is a system that is out of equilibrium. Life takes in and uses energy, altering its environment in the process. Without life, for example, our planet would not have an oxygen-rich atmosphere, as chemical reactions tend to deplete oxygen. The proliferation of left-handed amino acids is another example we see on Earth; life is made up of left-handed amino acids, but not their mirror-images. Such a lopsided situation is an indication of an environment out of whack—and perhaps life.

    However, what we can search for also depends on what’s practical. As a result, NASA’s strategy for searching out life on other planets has generally been to “follow the water,” looking for life similar to that on Earth, Porco said, because that’s what we know how to find. Porco called on other scientists on the panel to come up with a “working definition” of life that could give planetary scientists guidance as to what else they should look for. For example, on other worlds, life might form in liquid hydrocarbons instead of water, such as on Saturn’s moon, Titan. Different markers might reveal life in hydrocarbon seas.

    Rather than searching for new forms of life on Earth or in the stars, other scientists study the question from the bottom up, looking for possible precursors of life. Chemist David Lynn of Emory University in Atlanta points out that misfolded proteins—like the those implicated in neurodegenerative diseases such as Alzheimer’s—show some similarities to life, namely that they can generate diversity in the different ways that they fold, and can undergo chemical evolution, in which those folded proteins are selected not genetically, but chemically. Such precursors could form complex chemical networks, which might be the foundation of radically different life elsewhere in the universe.

    Biochemist John Chaput of Arizona State University, Tempe, takes the approach of working backward from the central dogma, asking if early life could have used a simpler precursor to RNA and DNA. He studies threose nucleic acid, which is not found in nature but can be synthesized in the lab. It forms a similar structure to DNA, but with a different backbone and would’ve been simpler to produce and replicate on primordial Earth. “Life did not choose DNA or RNA out of chemical necessity,” he said. “There may have been many alternative paths to the evolution of life.”

    See the full article here.

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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  • richardmitnick 6:39 am on February 14, 2015 Permalink | Reply
    Tags: , , Exoplanets, ,   

    From NBC News: “Weird Sub-Neptunes and Super-Earths Pop Up in Kepler’s Planet Search” 

    NBC News

    NBC News

    February 13th 2015
    Alan Boyle

    One of the most common kinds of planets detected by NASA’s Kepler telescope appears to be a type that doesn’t exist in our own solar system, a leading astronomer on the Kepler team said Friday.

    Habitable planets Current Potential

    NASA Kepler Telescope
    Kepler

    This type of planet has a size in the range between two and four times Earth’s diameter, but it shouldn’t be called a “super-Earth” or a “mini-Neptune,” said Berkeley astronomer Geoff Marcy, one of the world’s most experienced planet-hunters. For now, he’s calling them “sub-Neptunes.”

    Based on an analysis of the Kepler planets’ sizes and densities, sub-Neptunes should have a rocky core that’s swathed in a thick layer of hydrogen and helium gas. That combination distinguishes them from rocky planets like Earth, as well as gas giants like Jupiter and ice giants like Neptune.

    “They dominate the planet census, and yet none of them are found in the solar system,” Marcy said here during a symposium at the annual meeting of the American Association for the Advancement of Science.

    Such planets also have been called “warm Neptunians” or “gas dwarfs.”

    Marcy said the analysis suggests that rocky planets can’t get much larger than 1.5 to two times Earth’s width. But that doesn’t mean we should give up on finding alien analogs to Earth, he said. The Kepler mission’s scientists already have identified scores of planets that are less than twice Earth’s width, and they say our Milky Way galaxy must have lots more such worlds.

    “There are billions of Earth-size planets, and many of them exist in the habitable zone,” said NASA researcher Bill Borucki, the Kepler mission’s principal investigator. “The question is, why hasn’t SETI picked up the signal?”

    Another member of the Kepler science team, Natalia Batalha of San Jose State University and NASA’s Ames Research Center, showed off a list of 29 potential super-Earths that lie within their parent stars’ habitable zones, where liquid water and possibly life could conceivably exist.

    One of the aims of the Kepler mission is to identify potentially habitable Earth-class planets, a category known as eta-earth.

    “We now have a very highly reliable sample of small-planet candidates in the habitable zone of both M- and K-type stars [red and orange dwarfs] that will enable an eta-Earth determination for this class of stars,” Batalha said.

    She added that similar determinations may be made for some of the small planets that Kepler has detected around sunlike stars, known as G-type stars. However, it’s still debatable whether the candidates on Kepler’s current list should be classified as rocky planets in the traditional sense, or as sub-Neptunes.

    Batalha’s list doesn’t yet include any Earth-size planets in Earthlike orbits around sunlike stars, but after Friday’s symposium, she hinted that it may not be long before such long-sought worlds start popping up in the Kepler database.

    “There are going to be more,” she told NBC News.

    See the full article here.

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  • richardmitnick 2:45 pm on January 30, 2015 Permalink | Reply
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    From ESO- “ESOcast 71: New Exoplanet-hunting Telescopes on Paranal” 


    European Southern Observatory

    This ESOcast takes a close look at an unusual new group of small telescopes that has recently achieved first light at ESO’s Paranal Observatory in northern Chile.

    Watch, enjoy, learn.

    See the full article here.

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  • richardmitnick 6:07 am on January 24, 2015 Permalink | Reply
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    From LLNL: “New research re-creates planet formation, super-Earths and giant planets in the laboratory” 


    Lawrence Livermore National Laboratory

    Jan. 22, 2015

    Breanna Bishop
    bishop33@llnl.gov
    925-423-9802

    1
    New laser-driven shock compression experiments on stishovite, a high-density form of silica, provide thermodynamic and electrical conductivity data at unprecedented conditions and reveal the unusual properties of rocks deep inside large exoplanets and giant planets. Photo by E. Kowaluk, LLE

    New laser-driven compression experiments reproduce the conditions deep inside exotic super-Earths and giant planet cores, and the conditions during the violent birth of Earth-like planets, documenting the material properties that determined planet formation and evolution processes.

    The experiments, reported in the Jan. 23 edition of Science, reveal the unusual properties of silica — the key constituent of rock — under the extreme pressures and temperatures relevant to planetary formation and interior evolution.

    Using laser-driven shock compression and ultrafast diagnostics, Lawrence Livermore National Laboratory (LLNL) physicist Marius Millot and colleagues from Bayreuth University (Germany), LLNL and the University of California, Berkeley were able to measure the melting temperature of silica at 500 GPa (5 million atmospheres), a pressure comparable to the core-mantle boundary pressure for a super-Earth planet (5 Earth masses), Uranus and Neptune. It also is the regime of giant impacts that characterize the final stages of planet formation.

    “Deep inside planets, extreme density, pressure and temperature strongly modify the properties of the constituent materials,” Millot said. “How much heat solids can sustain before melting under pressure is key to determining a planet’s internal structure and evolution, and now we can measure it directly in the laboratory.”

    In combination with prior melting measurements on other oxides and on iron, the new data indicate that mantle silicates and core metal have comparable melting temperatures above 300-500 GPa, suggesting that large rocky planets may commonly have long-lived oceans of magma – molten rock – at depth. Planetary magnetic fields can be formed in this liquid-rock layer.

    “In addition, our research suggests that silica is likely solid inside Neptune, Uranus, Saturn and Jupiter cores, which sets new constraints on future improved models for the structure and evolution of these planets,” Millot said.

    Those advances were made possible by a breakthrough in high-pressure crystal growth techniques at Bayreuth University in Germany. There, Natalia Dubrovinskaia and colleagues managed to synthesize millimeter-sized transparent polycrystals and single crystals of stishovite, a high-density form of silica (SiO2) usually found only in minute amounts near meteor-impact craters.

    Those crystals allowed Millot and colleagues to conduct the first laser-driven shock compression study of stishovite using ultrafast optical pyrometry and velocimetry at the Omega Laser Facility at the University of Rochester’s Laboratory for Laser Energetics.

    “Stishovite, being much denser than quartz or fused-silica, stays cooler under shock compression, and that allowed us to measure the melting temperature at a much higher pressure,” Millot said. “Dynamic compression of planetary-relevant materials is a very exciting field right now. Deep inside planets hydrogen is a metallic fluid, helium rains, fluid silica is a metal and water may be superionic.”

    In fact, the recent discovery of more than 1,000 exoplanets orbiting other stars in our galaxy reveals the broad diversity of planetary systems, planet sizes and properties. It also sets a quest for habitable worlds hosting extraterrestrial life and shines new light on our own solar system. Using the ability to reproduce in the laboratory the extreme conditions deep inside giant planets, as well as during planet formation, Millot and colleagues plan to study the exotic behavior of the main planetary constituents using dynamic compression to contribute to a better understanding of the formation of the Earth and the origin of life.

    Co-authors on this paper include David Braun, Peter Celliers, Gilbert Collins and Jon Eggert of LLNL; Natalia Dubrovinskaia, Ana Černok, Stephan Blaha and Leonid Dubrovinsky of Bayreuth University; and Raymond Jeanloz of the University of California, Berkeley.

    See the full article here.

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  • richardmitnick 12:15 pm on January 18, 2015 Permalink | Reply
    Tags: , , Exoplanets, U Toronto   

    From U Toronto: “Planets outside our solar system more hospitable to life than we’d thought” 

    U Toronto Bloc

    University of Toronto

    Jan 16, 20015
    Sean Bettam

    A study by astrophysicists at the University of Toronto suggests that exoplanets – planets outside our solar system – are more likely to have liquid water and be more habitable than we thought.

    1
    Artist’s impression of the exoplanet Tau Boötis b (image by: ESO/L. Calçada)

    “Planets with potential oceans could have a climate that is much more similar to Earth’s than previously expected,” said Jérémy Leconte, a postdoctoral fellow at the Canadian Institute for Theoretical Astrophysics (CITA) and the Centre for Planetary Sciences at the University of Toronto, and lead author of a study published January 15 in Science Express.

    Scientists have thought that exoplanets behave in a manner contrary to that of Earth – that is, they always show their same side to their star. If so, exoplanets would rotate in sync with their star so that there is always one hemisphere facing it while the other hemisphere is in perpetual cold darkness.

    Leconte’s study suggests, however, that as exoplanets rotate around their stars, they spin at such a speed as to exhibit a day-night cycle similar to Earth.

    “If we are correct, there is no permanent, cold night side on exoplanets causing water to remain trapped in a gigantic ice sheet. Whether this new understanding of exoplanets’ climate increases the ability of these planets to develop life remains an open question.”

    Leconte and his team reached their conclusions via a three-dimensional climate model they developed to predict the effect of a given planet’s atmosphere on the speed of its rotation, which results in changes to its climate,” said Leconte. “Atmosphere is a key factor affecting a planet’s spin, the impact of which can be of enough significance to overcome synchronous rotation and put a planet in a day-night cycle.”

    Though astronomers are still awaiting observational evidence, theoretical arguments suggest that many exoplanets should be able to maintain an atmosphere as massive as that of Earth. In Earth’s case – with its relatively thin atmosphere – most of the light from the Sun reaches the surface of the planet, maximizing the effect of heating throughout the atmosphere and producing a more moderate climate across the planet. By creating temperature differences at the surface, between day and night and between equator and poles, the solar heating drives winds that redistribute the mass of the atmosphere.

    The impact is so significant that it overcomes the effect of tidal friction exerted by a star on whatever satellite is orbiting it, much like Earth does on the Moon.

    “The Moon always shows us the same side, because the tides raised by Earth create a friction that alters its spin,” said Leconte. “The Moon is in synchronous rotation with Earth because the time it takes to spin once on its axis equals the time it takes for it to orbit around Earth. That is why there is a dark side of the moon. The tidal theory, however, neglects the effects of an atmosphere.”

    The researchers say that a large number of known terrestrial exoplanets should not be in a state of synchronous rotation, as initially believed. While their models show that they would have a day-night cycle making them much more similar to Earth, the duration of their days could last between a few weeks and a few months.

    The findings are reported in the paper Asynchronous rotation of Earth-mass planets in the habitable zone of lower-mass stars published January 15 in Science Express. The work was supported by grants from the Natural Sciences and Engineering Research Council of Canada.

    See the full article here.

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  • richardmitnick 7:26 am on January 14, 2015 Permalink | Reply
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    From ESO: “New Exoplanet-hunting Telescopes on Paranal” 


    European Southern Observatory

    14 January 2015
    Peter Wheatley
    University of Warwick
    Coventry, United Kingdom
    Tel: +44 247 657 4330
    Email: P.J.Wheatley@warwick.ac.uk

    Heike Rauer
    Deutsches Zentrum für Luft- und Raumfahrt (DLR) / Institut für Planetenforschung
    Berlin, Germany
    Tel: +49 30 67055 430
    Email: heike.rauer@dlr.de

    Stéphane Udry
    Observatoire de l’Université de Genève
    Geneva, Switzerland
    Tel: +41 22 379 24 67
    Email: stephane.udry@unige.ch

    Ather Mirza
    University of Leicester
    Leicester, United Kingdom
    Tel: +44 116 252 3335
    Email: pressoffice@le.ac.uk

    David Azocar
    Universidad de Chile
    Santiago, Chile
    Email: dazocar@das.uchile.cl

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany

    Tel: +49 89 3200 6655
    Email: rhook@eso.org

    The Next-Generation Transit Survey (NGTS) has achieved first light at ESO’s Paranal Observatory in northern Chile. This project will search for transiting exoplanets — planets that pass in front of their parent star and hence produce a slight dimming of the star’s light that can be detected by sensitive instruments. The telescopes will focus on discovering Neptune-sized and smaller planets, with diameters between two and eight times that of Earth.

    1

    ESO Paranal Facilities
    ESO/Paranal

    The Next-Generation Transit Survey (NGTS) is a wide-field observing system made up of an array of twelve telescopes, each with an aperture of 20 centimetres [1]. This new facility, built by a UK, Swiss and German consortium, is located at ESO’s Paranal Observatory in northern Chile and benefits from the superb observing conditions and excellent support facilities available at this site.

    “We needed a site where there were many clear nights and the air was clear and dry so that we could make very accurate measurements as often as possible — Paranal was the best choice by far,” says Don Pollacco of the University of Warwick in the UK and one of the NGTS project leads.

    NGTS is designed to operate in a robotic mode and it will continuously monitor the brightness of hundreds of thousands of comparatively bright stars in the southern skies. It is searching for transiting exoplanets and will reach a level of accuracy in measuring the brightness of stars — one part in a thousand — that has never before been attained with a ground-based wide-field survey instrument [2].

    This great accuracy of brightness measurement, across a wide field, is technically demanding, but all the key technologies needed for NGTS were demonstrated using a smaller prototype system, which operated on La Palma in the Canary Islands during 2009 and 2010. NGTS also builds on the success of the SuperWASP experiment, which up to now leads in the detection of large gaseous planets.

    The discoveries of NGTS will be studied further using other larger telescopes, including the ESO Very Large Telescope[pictured above]. One goal is to find small planets that are bright enough for the planetary mass to be measured. This will allow planetary densities to be deduced, which in turn provides clues about the composition of the planets. It may also be possible to probe the atmospheres of the exoplanets whilst they are in transit. During the transit some of the star’s light passes through the planet’s atmosphere, if it has one, and leaves a tiny, but detectable, signature. So far only a few such very delicate observations have been made, but NGTS should provide many more potential targets.

    This is the first telescope project hosted, but not operated, by ESO on Paranal. Several telescope projects operating under similar arrangements are already at work at the older La Silla Observatory. The NGTS data will flow into the ESO archive system and will be available to astronomers worldwide for decades to come.

    ESO LaSilla Long View
    ESO at LaSilla

    Peter Wheatley, one of the NGTS project leads from the University of Warwick, concludes: “We are excited to begin our search for small planets around nearby stars. The NGTS discoveries, and follow-up observations by telescopes on the ground and in space, will be important steps in our quest to study the atmospheres and composition of small planets such as the Earth.”

    The NGTS Consortium is composed of the University of Warwick, UK; the Queen’s University of Belfast, UK; the University of Leicester, UK; the University of Cambridge, UK; Geneva University, Switzerland and DLR Berlin, Germany.
    Notes

    [1] The NGTS telescopes are modified versions of small high-quality commercial telescopes made by Astro Systeme Austria (ASA). The NGTS cameras are modified ikon-L cameras by Andor Technology Ltd (http://www.andor.com) built around red-sensitive deep-depletion CCDs by e2v (http://www.e2v.com).

    [2] NASA’s orbiting Kepler mission has a higher accuracy of stellar brightness measurement but probes a smaller region of the sky than NGTS. The wider NGTS search will find brighter examples of small exoplanets that are better suited for detailed study.

    NASA Kepler Telescope
    NASA/Kepler

    See the full article here.

    SuperWASP telescope
    SuperWASP is the UK’s leading extra-solar planet detection programme. It originally comprised a consortium of eight academic institutions: Cambridge University, the Instituto de Astrofisica de Canarias, the Isaac Newton Group of telescopes, Keele University, Leicester University, the Open University, Queen’s University Belfast and St. Andrews University. The WASP project is currently funded and operated by Warwick University and Keele University.

    SuperWASP consists of two robotic observatories that operate continuously all year around, allowing us to cover both hemispheres of the sky. The first, SuperWASP-North is located on the island of La Palma amongst the Isaac Newton Group of telescopes (ING). The second, SuperWASP-South is located at the site of the South African Astronomical Observatory (SAAO), just outside Sutherland, South Africa. The observatories each consist of eight wide-angle cameras that simultaneously monitor the sky for planetary transit events. A transit occurs when a planet passes in front of its parent star temporarily blocking some of the light from it. The eight wide-angle cameras allow us to monitor millions of stars simultaneously enabling us to detect the rare transit events.

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  • richardmitnick 2:13 pm on January 7, 2015 Permalink | Reply
    Tags: , , Exoplanets,   

    From SETI: “No Signals from Newest Kepler Planet” 


    SETI Institute

    Jan 7, 2015

    SETI Seth Shostak
    By Seth Shostak, Senior Astronomer and Director of SETI Research

    A newly discovered planet has been observed with the Allen Telescope Array in a search for radio signals that would betray technically sophisticated inhabitants, but no transmissions have been detected.


    Allen Telescope Array at Hat Creek Observatory

    Allen Telescope Array
    Allen Telescope Array

    The planet is known as Kepler 116454b, and orbits an orange dwarf star in the constellation Pisces. It is 180 light-years away.

    Jon Richards, of the SETI Institute’s Center for SETI Research, used the Allen Telescope Array to look for signals over the frequency range of 1000 – 2250 MHz.

    In May, 2013 the Kepler space telescope suffered a mechanical failure that ended its ability to accurately aim at the sky. But the telescope has resumed its search for planets in a new mode, using the pressure of sunlight to help it steady its gaze on the sky. Kepler 116454b is the first planet to be found by the reincarnated telescope, and its discovery was announced just before Christmas.

    NASA Kepler Telescope
    Kepler

    The planet orbits its home star in 9 days in an orbit three times smaller than Mercury’s orbit around the Sun. Consequently, temperatures on this world – which is a so-called “super Earth” and larger than Earth but smaller than Neptune – are expected to be too hot for life as we know it.

    s
    Two renderings of possible super-Earths, with Earth itself to the right for comparison

    Nonetheless, and as centuries of experience have shown, observation sometimes trumps expectation, and that is why new exoplanets – whether they seem promising for life or not – are routinely observed by the SETI Institute with the Allen Telescope Array.

    The observations of Kepler 116454b will continue at higher frequencies, Richards notes.

    See the full article here.

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  • richardmitnick 10:46 am on January 1, 2015 Permalink | Reply
    Tags: , , , , , Exoplanets,   

    From SPACE.com: “Planets with Odd, Mercury-Like Orbits Could Host Life” 

    space-dot-com logo

    SPACE.com

    December 31, 2014
    Charles Choi

    Mercury has an oddball orbit — it takes longer for it to rotate on its axis and complete a day than it takes to orbit the sun and complete a year. Now, researchers suggest photosynthesis could take place on an alien planet with a similarly bizarre orbit, potentially helping support complex life.


    Orbit animation

    1
    During its first Mercury solar day (which is about 176 Earth days long) in orbit, NASA’s MESSENGER spacecraft imaged nearly the entire surface of Mercury to generate a global monochrome map at 250 meters per pixel resolution and a 1 kilometer per pixel resolution color map.
    Credit: NASA/JHU APL/CIW

    NASA Messenger satellite
    NASA/Messenger

    However, the scientists noted that the threat of prolonged periods of darkness and cold on these planets would present significant challenges to alien life, and could even potentially freeze their atmospheres. They detailed their findings in the International Journal of Astrobiology.

    Astronomers have discovered more than 1,700 alien planets in the past two decades, raising the hope that at least some might be home to extraterrestrial life. Scientists mostly focus the search for alien life on exoplanets in the habitable zones of stars. These are regions where worlds would be warm enough to have liquid water on their surfaces, a potential boon to life.

    Although many exoplanets are potentially habitable, they may differ from Earth significantly in one or more ways. For instance, habitable planets around dim red dwarf stars orbit much closer than Earth does to the sun, sometimes even closer than Mercury’s distance.

    Red dwarfs are of interest as possible habitats for life because they are the most common stars in the universe — if life can exist around red dwarfs, then life might be very common across the cosmos. Recent findings from NASA’s Kepler Space Observatory suggest that at least half of all red dwarfs host rocky planets that are one-half to four times the mass of Earth.

    NASA Kepler Telescope
    NASA/Kepler

    Since a planet in the habitable zone of a red dwarf orbits very near its star, it experiences much stronger gravitational tidal forces than Earth does from the sun, which slows the rate at which those worlds spin. The most likely result of this slowdown is that the planet enters what is technically called a 1:1 spin orbit resonance, completing one rotation on its axis every time it completes one orbit around its star.

    This rate of rotation means that one side of that planet will always face toward its star, while the other side will permanently face away, just as the moon always shows the same side to Earth. One recent study suggests that such “tidally locked” planets may develop strange lobster-shaped oceans basking in the warmth of their stars on their daysides, while the nightsides of such worlds are mostly covered in an icy shell.

    However, if a habitable red dwarf planet has a very eccentric orbit — that is, oval-shaped — it could develop what is called a 3:2 spin orbit resonance, meaning that it rotates three times for every two orbits around its star. Mercury has such an unusual orbit, which can lead to strange phenomena. For instance, at certain times on Mercury, an observer could see the sun rise about halfway and then reverse its course and set, all during the course of one mercurial day. Mercury itself is not habitable, since it lacks an atmosphere and experiences temperatures ranging from 212 to 1,292 degrees Fahrenheit (100 to 700 degrees Celsius).

    “If the sun were less intense, Mercury would be within the habitable zone, and therefore life would have to adapt to strange light cycles,” said lead study author Sarah Brown, an astrobiologist at the United Kingdom Center for Astrobiology in Edinburgh, Scotland.

    Light is crucial for photosynthesis, the process by which plants and other photosynthetic organisms use the sun’s rays to create energy-rich molecules such as sugars. Most life on Earth currently depends on photosynthesis or its byproducts in one way or the other, and while primitive life can exist without photosynthesis, it may be necessary for more complex multicellular organisms to emerge because the main source for oxygen on Earth comes from photosynthetic life, and oxygen is thought to be necessary for multicellular life to arise.

    To see what photosynthetic life might exist on a habitable red dwarf planet with an orbit similar to Mercury’s, scientists calculated the amount of light that reached all points on its surface. Their model involved a planet the same mass and diameter as the Earth with a similar atmosphere and amount of water on its surface. The red dwarf star was 30 percent the sun’s mass and 1 percent as luminous, giving it a temperature of about 5,840 degrees Fahrenheit (3,225 degrees Celsius) and a habitable zone extending from 10 to 20 percent of an astronomical unit (AU) from the star. (One AU is the average distance between Earth and the sun.)

    The scientists found that the amount of light the surface of these planets received concentrated on certain bright spots. Surprisingly, the amount of light these planets receive does not just vary over latitude as it does on Earth, where more light reaches equatorial regions than polar regions, but also varies over longitude. Were photosynthetic life to exist on worlds with these types of orbits, “one would expect to find niches that depend on longitude and latitude, rather than just latitude,” said study co-author Alexander Mead, a cosmologist at the Royal Observatory, Edinburgh, in Scotland.

    The research team found these planets could experience nights that last for months. This could pose major problems for photosynthetic life, which depends on light. Still, the scientists noted that many plants can store enough energy to last through 180 days of darkness. Moreover, some photosynthetic microbes spend up to decades dormant in the dark, while others are mixotrophic, which means they can survive on photosynthesis when light is abundant and switch to devouring food when light is absent.

    Another problem these long spans of darkness pose for life is the cold, which could freeze the atmospheres of these planets. Still, the investigators note that heat can flow from the dayside of such a planet to its nightside and prevent this freezing if that planet’s atmosphere is sufficiently dense and can trap infrared light from the planet’s star. This heat flow could lead to very strong winds, but this does not necessarily make the world uninhabitable, they added.

    “Life having to cope with such tidally driven resonances could be common in the universe,” Mead said. “It changes one’s perception of what habitable planets in the universe would be like. There are many possibilities that are very un-Earth-like.”

    However, the researchers noted that the strength of a world’s magnetic field depends in large part on how quickly it spins, which suggests that planets with orbits like Mercury’s might have relatively weak magnetic fields. This could mean these worlds are not as good at deflecting harmful electrically charged particles streaming from their red dwarfs and other stars that can damage organisms and strip off the atmospheres of these planets.

    The investigators suggested that dense atmospheres could help keep such planets habitable in the face of radiation from space. They added that life might be confined to certain spots on the surfaces of those planets that experience relatively safe levels of radiation.

    Are astronomers capable of detecting habitable planets with a 3:2 spin orbit resonance?

    “Measuring the day length of extrasolar planets is enormously difficult, and the first day length measurements for any extrasolar planets were only published this year,” Mead said. “Such a measurement for the planets we discuss would be much more difficult due to the fact that they are small, rocky planets around faint stars. This means that we are probably a long way from measuring the spin rates of such habitable worlds.”

    See the full article here.

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  • richardmitnick 9:13 am on December 26, 2014 Permalink | Reply
    Tags: , , , , , Exoplanets, , ,   

    From Dennis Overbye at NYT: “Do Aliens Know It’s Christmas?” 

    New York Times

    The New York Times

    DEC. 22, 2014
    NYT Dennis Overbye Older
    Dennis Overbye

    A star appeared in the East.

    Following it, so the biblical story goes, three Magi urged on by a nervous King Herod arrived in Bethlehem and discovered the news that many of us celebrate with bells, lights and too much sugar and alcohol every year at this time: The son of God had come to die for our sins.

    Peace on earth and good will to men is fine, as far as it goes. But some astronomers and forward-thinking theologians wonder how the rest of the universe is supposed to get the message.

    If your dog can go to heaven, can E. T.? Astronomers have discovered in the last two decades that there are probably tens of billions of potentially habitable planets in the Milky Way. Only last week, NASA scientists reported that Mars had blown a methane sigh into the face of the Curiosity rover, though whether from microbes or geochemical grumblings may not be known until there are geologists’ boots on the Red Planet.

    NASA Mars Curiosity Rover
    NASA/Curiosity

    So it’s not so crazy to imagine other living creatures scattered through the billions of years and light-years of cosmic history.

    Did Christ come to die for their sins, too?

    Or as Geoffrey Marcy, an exoplanet explorer and holder of the Watson and Marilyn Alberts Chair in the Search for Extraterrestrial Intelligence at the University of California, Berkeley, said not long ago in an email, “But do they know it’s Christmas?”

    Surely, earthlings were not the only beings in the Milky Way blessed in God’s eyes, he elaborated, saying that he liked to tease public audiences with the question. “Conversations about religion with intelligent beings from an exoplanet might jolt humanity into realizing how parochial our beliefs are,” he said.

    Pope Francis suggested in a homily in May that he would baptize Martians if they landed in St. Peter’s Square and asked for it.

    How, you may ask, might E.T. have sinned? On Earth, violence and suffering are embedded in the Darwinian struggle for survival that produced us, says Ted Peters, a professor who runs a group on “astrotheology” at the Center for Theology and the Natural Sciences in Berkeley. If aliens are made of the same stuff we are, Dr. Peters wrote in the Philosophical Transactions of the Royal Society in 2011, “might they also share the ambiguity between good and evil that we are familiar with?”

    But what if they are computers or other forms of artificial intelligence that futurists say might ultimately supplant us as masters of the universe?

    Christian scholars like Dr. Peters and indeed the pope agree that the possibility of redemption probably extends to all of creation, even perhaps the inanimate world.

    “How could he be God and leave extraterrestrials in sin?” asks the Rev. George V. Coyne, the former director of the Vatican Observatory and now a Jesuit priest who holds the McDevitt Chair of Religious Philosophy at Le Moyne College in Syracuse, in the 2000 book Many Worlds: The New Universe, Extraterrestrial Life and the Theological Implications, edited by the astronomer Steven J. Dick, a former chief historian for NASA. “After all, he was good to us. Why should he not be good to them?”

    This has engendered a sort of how-many-angels-can-dance-on-the-head-of-a-pin argument about whether Christ died for the entire cosmos, or whether the son of God or the metaphysical equivalent has to be born and die on every populated planet.

    Each alternative sounds ridiculous on the face of it. The first alternative would make Earth the center of the universe again, not just in space but in time, carrying the hopes for the salvation of beings that lived and died millions or billions of years ago and far, far away.

    The second alternative would be multiple incarnations, requiring every civilization to have its own redeemer — “its own adventure with God,” in the words of Professor Peters. That is hardly better. As the old troublemaker Thomas Paine wrote in The Age of Reason, “In this case, the person who is irreverently called the son of God, and sometimes God himself, would have nothing else to do than to travel from world to world, in an endless succession of deaths, with scarcely a momentary interval of life.”

    Distinguished theologians have come down on different sides of this issue; after all, it’s not up to us to say what God could or could not do. “God doesn’t seem to be limited by history and communication,” Dr. Peters said in an interview, playing the devil’s advocate, so to speak, for the notion of a single incarnation for the entire cosmos. In that case, the consequences would not be limited to “people who get emails about it.”

    “Every sentient being is blessed by God’s grace whether they know about it or not,” he said.

    Seeking scientific as well as spiritual guidance, I dialed up Guy Consolmagno at the Vatican Observatory. He is a Jesuit priest and a co-author, with his fellow Jesuit Paul Mueller, of Would You Baptize an Extraterrestrial? … And Other Questions from the Astronomer’s In-box at the Vatican Observatory.

    Vatican Observatory
    Vatican Observatory Interior
    Vatican Observatory

    Brother Consolmagno spent 10 years working and teaching as a planetary scientist, specializing in meteorites, before joining the Jesuits. Last year, he was awarded the Carl Sagan Medal by the Division for Planetary Sciences of the American Astronomical Society, for communication in planetary science. He said that Christmas for aliens could be a wonderful story, but that he didn’t have any answers and that that was part of the fun.

    “One incarnation seems absurd but not inconsistent with the data,” he said by phone from Florida, where he was watching manatees.

    There is no data, I pointed out.

    “Exactly!” he responded, laughing.

    Contrary to popular perception, he said, religion, like science, is not a closed book. “Science,” he said, “is stuff we understand about truths we only partially grasp. Religion is trying to get closer to truths we don’t understand.”

    The more you know, the more you know you don’t understand, he said. “That’s called progress.”

    The challenge in any person’s or species’ life, he added, is how to learn others’ truths without giving up your own.

    Dr. Marcy, with tongue fairly firmly in cheek, evoked what he called “the multigod model of the universe.”

    There might be room in the universe for more than one truth, he said, if every inhabited planet had its own gods. The inhabitants might be as certain of their beliefs as we humans are of ours.

    “The deities have carved out their operating galactic territories, like so many cosmic Corleone families,” Dr. Marcy said.

    “Only with SETI research,” he went on, referring to the search for extraterrestrial intelligence, “will we learn whether our particular God is alone in the universe.”

    His point was echoed, if less ironically, by Nancy Ellen Abrams, a lawyer, philosopher and author of a forthcoming book, A God That Could Be Real: Spirituality, Science and the Future of Our Planet, which argues that God is an emergent phenomenon, a result of the complexity of the universe and human aspirations rather than the cause of them — although no less real for that. “Our god is the god of humanity; it has nothing to do with aliens,” she said in an interview.

    In the best of all possible universes, all these truths and gods would mysteriously and perhaps revelatorily overlap. But maybe that is wishful thinking and there is another, more chilling answer to Christmas.

    Take that star in the East; it was the subject of a classic story by Arthur C. Clarke, a science fiction author and space visionary.

    In The Star, published in 1955, an expedition to the site of an old supernova explosion discovers the remains of an ancient civilization, carefully preserved because its members knew they were about to be obliterated. The story is told through the eyes of the astrophysicist onboard, a Jesuit. He is able to figure out exactly when the explosion that doomed this race took place, and exactly what it would have looked like 2,000 years ago from Earth.

    “There can be no reasonable doubt,” he concludes, “the ancient mystery is solved at last. Yet, oh God, there were so many stars you could have used. What was the need to give these people to the fire, that the symbol of their passing might shine above Bethlehem?”

    Brother Consolmagno, who was a science fiction aficionado as an undergraduate at M.I.T., knows the story.

    “That’s not the kind of god I’m happy with,” he said.

    See the full article here.

    Please help promote STEM in your local schools.

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