- Should We Phone E.T.? Scientists Urge to Seek Contact with Aliens
- Researchers to Study Fruit Flies in Space in 2016
- Boeing’s Space Efforts to Be Managed by Newly Created Organization
- Interstellar Technology Throws Light on Spinning Black Holes
- Arianespace to Launch South Korean Satellites
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Posted: 14 Feb 2015 05:11 AM PST
They don't hold out much hope that Vulcans will arrive on our doorsteps intoning "live long and prosper," but many astronomers believe that making radio contact with an alien civilization would fundamentally alter humanity for the better. For fifty years, however, they have searched the sky for signs of intelligent beings elsewhere in the universe with no result. Some think it's time to start sending our own messages to the stars in hope that someone up there will reply. So-called 'active SETI' is controversial. Astrophysicist Steven Hawking famously cautioned against shouting out our presence into the void, saying that first contact "… didn't turn out very well for the Native Americans." In response to such concerns, the nonprofit Search for Extraterrestrial Intelligence (SETI) Institute held one of the first public debates on the wisdom of active SETI, at the American Association for the Advancement of Science (AAAS) annual meeting. “With active SETI ... we take an active role in transmitting intentional, powerful information-rich signals to other civilizations in the hope of getting a response,” Douglas Vakoch of the SETI Institute said during a news briefing on Thursday.
The chances of someone picking up the message are better than ever. Recent data "encourages those who are optimistic about life in the universe," said astrobiologist David Grinspoon of the Planetary Science Institute at a Feb. 12 news conference. Scientists now believe one in five sun-like stars have planets with conditions suitable for life, he reported. And research on extreme organisms on Earth, which eke out existence in the most challenging of environments, suggests that life could survive in even more unlikely places. The more common life in general is, Grinspoon suggested, the more probable that some of it has evolved intelligence and perhaps the ability to communicate.
Vakoch argued that the time has come to stop waiting for some other galactic civilization to establish contact with us and make the first gesture ourselves. After all, if no one is transmitting messages, we don't have much chance of hearing one. "Sometimes we talk about SETI as an attempt to join the galactic club," Vakoch said, "but no one ever talks about paying our dues or even submitting an application."
Astronomers have listened for signals from alien civilisations since 1960, when the Cornell University astronomer Frank Drake co-opted the national observatory at Green Bank, West Virginia, to launch Project Ozma. In more than 50 years since, no convincing signals have been picked up.
The first step, Vakoch said, is to send out a signal that an extraterrestrial version of the SETI project could pick up. The message, he suggested, could be sent in the spare time of the Arecibo telescope in Puerto Rico, which Drake used to send a coded message to a distant star cluster in 1974.
NASA placed gold-anodized aluminium plaques on board the 1972 Pioneer 10 and 1973 Pioneer 11 spacecraft, featuring a pictorial message, in case either Pioneer 10 or 11 is intercepted by extraterrestrial life. The plaques show the nude figures of a human male and female along with several symbols that are designed to provide information about the origin of the spacecraft.
Speaking out against blabbing our presence to the stars was David Brin of Futures Unlimited in San Diego. Perhaps we haven't heard from alien civilizations because we're listening in the wrong place or with the wrong technology, he said. Perhaps they are waiting for us to make the first move. Or, maybe there's a more sinister explanation. Given the lack of any solid data, he said, SETI scientists' assumption that any galactic civilization capable of communicating with us would be benign is a dangerous one.
Brin called for a self-imposed halt on active broadcasts until there can be a global discussion of the potential risks and benefits. He compared this to the pause biologists placed on genetic engineering in the early 1990s to discuss the technology's risks and best practices. This moratorium, Brin said, ultimately resulted in better and safer research. In particular, he called for the inclusion of historians who could caution astronomers about the potential dangers of making contact. Here on Earth, Brin said, no first contact between peoples has ever been painless, even when there have been the best of intentions.
The possible benefits of making contact far outweigh the risks, said Seth Shostak, a senior astronomer at SETI. He argued that any alien civilization that could reach us to do us harm would be more than capable of detecting us already. Any extra terrestrial with technology just a few centuries beyond ours, he estimated, could find us based on the radio and television broadcasts we have inadvertently beamed into space since the mid-20th Century. "Our leakage is 70 light years into space," he said. "'I Love Lucy' is washing over the shores of a new planet out there on average once a day."
"Some of us at the institute are interested in 'active Seti', not just listening but broadcasting something to some nearby stars because maybe there is some chance that if you wake somebody up you'll get a response," he told BBC News.
Brin called Shostak's claims assertions based on assumptions rather than data. "We are learning so much so fast," Brin said. "Fifteen years ago we knew of no planets outside our solar system — now it's thousands." Wouldn't make more sense, he asked, to pause and learn more before doing something that could change the fate of the world forever? Perhaps the risks of shouting into the interstellar jungle are small, but they are real, he said. "What we are saying is 'Let's talk about it.'"
"I think it’s a waste of time at the present. It's like somebody trying to send an e-mail to somebody whose e-mail address they don’t know, and whose name they don’t know,” Drake siad about 'active SETI'.
"We have already sent signals into space that will alert the aliens to our presence with the transmissions and street lighting of the last 70 years. These emissions cannot be recalled," Shostak said.
Consequently some of science’s alien hunters have proposed being less passive. It’s time, they say, to launch “active SETI,” with a new acronym: METI, for messages to extraterrestrial intelligence.
Still, there are issues to consider in choosing the message. For one thing, it has to be composed in a form that intelligent aliens would be able to decipher. Shostak has a suggestion in that regard.
“Personally, I’ve said we should send the entire Internet, because that’s so redundant it’s like sending a lot of hieroglyphics to the 19th century. They can figure it out on the basis of the redundancy.”
So a sufficiently advanced civilization, well acquainted with analyzing big data, ought to be able to decode the Internet accurately. In which case, two possible responses are likely: The aliens will conclude that Earth should be immediately exterminated, or they will send back the favorite examples of their cat videos. In 2008, for instance, the tortilla chip company Doritos sent an advertisement from a radar station in Norway to a potentially habitable star system 42 light-years away.
The debate is just one step in an ongoing exploration of actively pinging the galaxy. The SETI Institute plans to hold a day-long workshop Saturday at its Mountain View campus. The meeting is slated to include the perspectives of historians and religious scholars, according to SETI Institute CEO David Black, who organized the meeting. The objective, Black said, is to start figuring out how to regulate and plan any active SETI efforts. Currently, he said, there's no law preventing people from renting time on a radio telescope and "firing off a signal." The potential impact of announcing ourselves to the galaxy is immense, he said, and he expects a long debate. If we decide to pick up the phone, the next question is what we want to say.
Credit: aaas.org, sciencenews.
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Posted: 14 Feb 2015 03:08 AM PST
Researchers will continue to study drosophilae, or fruit flies, in outer space in 2016. The research is aimed at working out mechanisms for astronauts’ protection from unfavourable factors in future interplanetary flights, said Dr. Sc. (Physics and Mathematics) Irina Ogneva, the lead researcher at the Biomedical Problems Institute of the Russian Academy of Sciences. "This year we are not planning to send fruit flies to space," Ogneva told TASS on Friday. "We received enough material for research on Earth. And so the next experiment is to be carried out next year."
Fruit flies have become a target of experiments in space last year.
The second generation of ‘space’ flies was bred on the Foton-M satellite along with the third generation of maggots, which spent 44.5 days in space.
At the end of last October the fourth generation of fruit flies lifted off aboard a spaceship and after living 12 days at the International Space Station (ISS) gave birth to the fifth generation of space maggots.
"The research will allow us to study processes of propagation of living species in the condition of zero gravity and to understand the processes when negative tendencies affect them at a cell level," Ogneva said.
"Cosmic radiation remains the main factor behind the frequency of mutations," she said. "Besides, living specimens are exposed to weightlessness, vibration and electromagnetic radiation among other factors. That’s why fruit flies are unique objectives for research.".
Credit: TASS
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Posted: 13 Feb 2015 02:59 PM PST
Boeing has announced the creation of BDS Development, an organization within its Defense, Space & Security (BDS) unit, which will centralize its defense and space efforts. The company stated that this move will enhance its performance on the pre-production development activities that significantly influence its ability to provide customers with the right capabilities at the right time and cost. So what does it mean for CST-100 spacecraft and Space Launch System (SLS) vehicle currently being developed by Boeing? “Both the CST-100 effort and SLS programs will now be managed by the BDS Development organization,” Todd Blecher, External Communications Director at BDS, told astrowatch.net. “The goal in establishing the organization is to improve Boeing’s performance on space and defense development activities by bringing key programs, people, processes, and resources together into an organization whose sole focus is meeting cost and schedule commitments during the development phase of the programs.”
BDS Development will be led by Jim O'Neill, who was president of the BDS Global Services & Support (GS&S) unit.
“This BDS Development organization is the next step in breaking the cost curve on our programs,” said BDS President and CEO Chris Chadwick. “We expect our customers to see step-function improvements in affordability and schedule performance as we more effectively apply engineering expertise, development program best practices, and program management and integration from across Boeing to our most important development activities.”
Boeing was selected in September 2014, to manufacture the CST-100 as part of NASA’s Commercial Crew Program. The spacecraft is designed to transport up to seven passengers or a mix of crew and cargo to low-Earth orbit destinations such as the International Space Station (ISS).
Boeing is also the prime contractor for the design, development, test and production of the SLS vehicle cryogenic stages, as well as development of the avionics suite. NASA’s SLS will be the most powerful rocket in history, designed for deep-space exploration endeavors.
On the list of programs overseen by BDS Development is also Boeing’s 502 small satellite. It is a 250 – 1000 kilogram satellite designed for single, dual and multiple manifest launches and can operate in geosynchronous, medium-Earth orbit, or low-Earth orbit.
BDS is one of the world's largest defense, space and security businesses and the world’s largest and most versatile manufacturer of military aircraft.
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Posted: 13 Feb 2015 01:11 PM PST
The team responsible for the Oscar-nominated visual effects at the centre of Christopher Nolan's epic, Interstellar, have turned science fiction into science fact by providing new insights into the powerful effects of black holes. In a paper published today, 13 February, in IOP Publishing's journal Classical and Quantum Gravity, the team describe the innovative computer code that was used to generate the movie's iconic images of the wormhole, black hole and various celestial objects, and explain how the code has led them to new science discoveries. Using their code, the Interstellar team, comprising London-based visual effects company Double Negative and Caltech theoretical physicist Kip Thorne, found that when a camera is close up to a rapidly spinning black hole, peculiar surfaces in space, known as caustics, create more than a dozen images of individual stars and of the thin, bright plane of the galaxy in which the black hole lives. They found that the images are concentrated along one edge of the black hole's shadow.
These multiple images are caused by the black hole dragging space into a whirling motion and stretching the caustics around itself many times. It is the first time that the effects of caustics have been computed for a camera near a black hole, and the resulting images give some idea of what a person would see if they were orbiting around a hole.
The discoveries were made possible by the team's computer code, which, as the paper describes, mapped the paths of millions of lights beams and their evolving cross-sections as they passed through the black hole's warped spacetime. The computer code was used to create images of the movie's wormhole and the black hole, Gargantua, and its glowing accretion disk, with unparalleled smoothness and clarity.
It showed portions of the accretion disk swinging up over the top and down under Gargantua's shadow, and also in front of the shadow's equator, producing an image of a split shadow that has become iconic for the movie.
This weird distortion of the glowing disk was caused by gravitational lensing--a process by which light beams from different parts of the disk, or from distant stars, are bent and distorted by the black hole, before they arrive at the movie's simulated camera.
This lensing happens because the black hole creates an extremely strong gravitational field, literally bending the fabric of spacetime around itself, like a bowling ball lying on a stretched out bed sheet.
Early in their work on the movie, with the black hole encircled within a rich field of distant stars and nebulae instead of an accretion disk, the team found that the standard approach of using just one light ray for one pixel in a computer code--in this instance, for an IMAX picture, a total of 23 million pixels--resulted in flickering as the stars and nebulae moved across the screen.
Co-author of the study and chief scientist at Double Negative, Oliver James, said: "To get rid of the flickering and produce realistically smooth pictures for the movie, we changed our code in a manner that has never been done before. Instead of tracing the paths of individual light rays using Einstein's equations--one per pixel--we traced the distorted paths and shapes of light beams."
Co-author of the study Kip Thorne said: "This new approach to making images will be of great value to astrophysicists like me. We, too, need smooth images."
Oliver James continued: "Once our code, called DNGR for Double Negative Gravitational Renderer, was mature and creating the images you see in the movie Interstellar, we realised we had a tool that could easily be adapted for scientific research."
In their paper, the team report how they used DNGR to carry out a number of research simulations exploring the influence of caustics--peculiar, creased surfaces in space--on the images of distant star fields as seen by a camera near a fast spinning black hole.
"A light beam emitted from any point on a caustic surface gets focussed by the black hole into a bright cusp of light at a given point," James continued. "All of the caustics, except one, wrap around the sky many times when the camera is close to the black hole. This sky-wrapping is caused by the black hole's spin, dragging space into a whirling motion around itself like the air in a whirling tornado, and stretching the caustics around the black hole many times."
As each caustic passes by a star, it either creates two new images of the star as seen by the camera, or annihilates two old images of the star. As the camera orbits around the black hole, film clips from the DNGR simulations showed that the caustics were constantly creating and annihilating a huge number of stellar images.
The team identified as many as 13 simultaneous images of the same star, and as many as 13 images of the thin, bright plane of the galaxy in which the black hole lives.
These multiple images were only seen when the black hole was spinning rapidly and only near the side of the black hole where the hole's whirling space was moving toward the camera, which they deduced was because the space whirl was 'flinging' the images outward from the hole's shadow edge. On the shadow's opposite side, where space is whirling away from the camera, the team deduced that there were also multiple images of each star, but that the whirl of space compressed them inward, so close to the black hole's shadow that they could not be seen in the simulations.
The published version of the paper 'Gravitational lensing by spinning black holes in astrophysics, and in the movie Interstellar' (James O, von Tunzelmann E, Franklin P and Thorne K S 2015 Class. Quantum Grav. 32 065001) is freely available online from Friday 13 February. It is available at http://iopscience.iop.org/
Credit: eurekalert.org
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Posted: 13 Feb 2015 12:05 PM PST
The Korea Aerospace Research Institute (KARI) has chosen Arianespace to launch the two satellites in its GEO-KOMPSAT-2 program. Mr. Jacques Breton, Senior Vice President, Sales & Customers of Arianespace and Mr. CHO Gwangrae, President of KARI, have signed today the launch contract for GEOKOMPSAT-2A & -2B. GEO-KOMPSAT-2A (GK2A) and GEO-KOMPSAT-2B (GK2B) will be orbited by Ariane 5 launchers in May 2018 and March 2019 from the Guiana Space Center, Europe's Spaceport in Kourou, French Guiana.
For nearly 25 years now, Arianespace and KOREA’s satellite technology research centers have developed a sound relationship, with the launch of both scientific microsatellites and the COMS multi-mission satellite. GEO-KOMPSAT-2A (GK2A) and GEO-KOMPSAT-2B (GK2B) will be the seventh and eighth satellites launched by Arianespace for South Korea.
Each of the GEO-KOMPSAT-2 satellites will weigh about 3,500 kg. at launch, and will be positioned in geostationary orbit at 128.2° East.
The satellites will be built by KARI at its facility in Daejeon, South Korea. The two governmental GEO-KOMPSAT-2 satellites will primarily perform meteorological observation and space weather monitoring (GK2A), and ocean and Earth environmental monitoring (GK2B).
Arianespace Chairman and CEO Stéphane Israël welcomed the contract signing, saying: "Arianespace is extremely proud of its selection by the Korean space agency, KARI. Our last launch for KARI occurred in 2010. Now, we have been chosen again by KARI to launch these two impressive meteorological observation missions. Contributing to Korean space achievements is a great honor for Arianespace. I would once again like to thank the Korea Aerospace Research Institute for selecting us. Arianespace will deliver."
Credit: arianespace.com
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