Space  

The apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilization and humanity's lack of contact with, or evidence for, such civilization continues as a massive survey of 100,000 galaxies has found no evidence of ET.

After searching 100,000 galaxies for signs of highly advanced extraterrestrial life, a team of scientists using observations from NASA's WISE orbiting observatory has found no evidence of advanced civilizations in them.

"The idea behind our research is that, if an entire galaxy had been colonized by an advanced spacefaring civilization, the energy produced by that civilization's technologies would be detectable in mid-infrared wavelengths — exactly the radiation that the WISE satellite was designed to detect for other astronomical purposes," said Jason T. Wright, an assistant professor of astronomy and astrophysics at the Center for Exoplanets and Habitable Worlds at Penn State University, who conceived of and initiated the research.

The research team's first paper about its Glimpsing Heat from Alien Technologies Survey (G-HAT), will be published in the Astrophysical Journal Supplement Series. Also among the team's discoveries are some mysterious new phenomena in our own Milky Way galaxy.

"Whether an advanced spacefaring civilization uses the large amounts of energy from its galaxy's stars to power computers, space flight, communication, or something we can't yet imagine, fundamental thermodynamics tells us that this energy must be radiated away as heat in the mid-infrared wavelengths," Wright said. "This same basic physics causes your computer to radiate heat while it is turned on."

"These galaxies are billions of years old, which should have been plenty of time for them to have been filled with alien civilizations, if they exist. Either they don't exist, or they don't yet use enough energy for us to recognize them."

Theoretical physicist Freeman Dyson proposed in the 1960s that advanced alien civilizations beyond Earth could be detected by the telltale evidence of their mid-infrared emissions. It was not until space-based telescopes like the WISE satellite that it became possible to make sensitive measurements of this radiation emitted by objects in space.

Roger Griffith, a postbaccalaureate researcher at Penn State and the lead author of the paper, scoured almost the entire catalog of the WISE satellite's detections — nearly 100 million entries — for objects consistent with galaxies emitting too much mid-infrared radiation. He then individually examined and categorized around 100,000 of the most promising galaxy images. Wright reports, "We found about 50 galaxies that have unusually high levels of mid-infrared radiation. Our follow-up studies of those galaxies may reveal if the origin of their radiation results from natural astronomical processes, or if it could indicate the presence of a highly advanced civilization."

In any case, Wright said, the team's non-detection of any obvious alien-filled galaxies is an interesting and new scientific result. "Our results mean that, out of the 100,000 galaxies that WISE could see in sufficient detail, none of them is widely populated by an alien civilization using most of the starlight in its galaxy for its own purposes. That's interesting because these galaxies are billions of years old, which should have been plenty of time for them to have been filled with alien civilizations, if they exist. Either they don't exist, or they don't yet use enough energy for us to recognize them," Wright said.

Related articles Eulerian Video Algorithm Will Be Perfect For Tricorder Devlelopment  Recalculation of Habitable Zone Exoplanets Reveals Them To Be More Common  System That Merges Human and Artificial Intelligence Awarded US Patent

"This research is a significant expansion of earlier work in this area," said Brendan Mullan, director of the Buhl Planetarium at the Carnegie Science Center in Pittsburgh and a member of the G-HAT team. "The only previous study of civilizations in other galaxies looked at only 100 or so galaxies, and wasn't looking for the heat they emit. This is new ground."

Matthew Povich, an assistant professor of astronomy at Cal Poly Pomona, and a co-investigator on the project, said "Once we had identified the best candidates for alien-filled galaxies, we had to determine whether they were new discoveries that needed follow-up study, or well-known objects that had a lot of mid-infrared emission for some natural reason." Jessica Maldonado, a Cal Poly Pomona undergraduate, searched the astronomical literature for the best of the objects detected as part of the study to see which were well known and which were new to science. "Ms. Maldonado discovered that about a half dozen of the objects are both unstudied and really interesting looking," Povich said.

"When you're looking for extreme phenomena with the newest, most sensitive technology, you expect to discover the unexpected, even if it's not what you were looking for," said Steinn Sigurdsson, professor of astronomy and astrophysics at Penn State's Center for Exoplanets and Habitable Worlds and a co-investigator on the research team. "Sure enough, Roger and Jessica did find some puzzling new objects. They are almost certainly natural astronomical phenomena, but we need to study them more carefully before we can say for sure exactly what's going on."

Among the discoveries within our own Milky Way galaxy are a bright nebula around the nearby star 48 Librae, and a cluster of objects easily detected by WISE in a patch of sky that appears totally black when viewed with telescopes that detect only visible light. "This cluster is probably a group of very young stars forming inside a previously undiscovered molecular cloud, and the 48 Librae nebula apparently is due to a huge cloud of dust around the star, but both deserve much more careful study," Povich said.

"As we look more carefully at the light from these galaxies," said Wright, "we should be able to push our sensitivity to alien technology down to much lower levels, and to better distinguish heat resulting from natural astronomical sources from heat produced by advanced technologies. This pilot study is just the beginning."


SOURCE  University of Pennsylvania via EurekAlert

By 33rd Square

Embed

 Search for Extraterrestrial Life  

In a lecture earlier this year, Dr. Jeff Kuhn describes a new idea for completing a nearby extraterrestrial cosmic census and describe some of the large telescope technology that exists today to undertake it. Kuhn proposes looking for heat signatures will help us find extraterrestrial civilizations, or ETCs.

Where are the extrasterrestrial civilizations and do we have the technology to find them?

We now know that we're surrounded by habitable extrasolar planets. Even half a century ago, before we knew of any extrasolar planets, Enrico Fermi speculated that the absence of any "proof" for extraterrestrial civilization could be important new for life on Earth. This is now known as the "Fermi Paradox."

Today his query is even more compelling. In the video below, Dr. Jeff Kuhn describes a new idea for completing a nearby extraterrestrial cosmic census and describe some of the technology that exists today to undertake it.

Related articles Higgs Particle Mass Suggests Doom For Our Universe  Recalculation of Habitable Zone Exoplanets Reveals Them To Be More Common  Planetary Resource's Arkyd Almost Ready For Space Prospecting

The detection of an extraterrestrial civilization (ETC), even without further communication, is important in many gnostic and practical aspects. For instance, one of the current burning issues for our civilization is surviving global climate changes because of increasing power generation.

Kuhn proposes that detecting more advanced civilizations will demonstrate a fundamental possibility that civilization can achieve a phase of sustainable global-scale power consumption.

For a half-century we have sought radio frequency evidence and, more recently, optical communications of ETCs. However, these approaches depend on finding alien transmissions, beam "leakage", or what could be called intentional electromagnetic signals from ETCs that are operating cosmic beacons.

The proposed Colossus telescope will employ a strategy for detecting an unintentional signal caused by alien planetary warming. Thanks to its large aperture and unique coronographic properties, it will be capable of detecting the thermodynamic signal from Earth-like ETC's within an interestingly large cosmic volume.

The outcome of such a dual wavelength, visible-IR, search will be largely independent of alien communication modes and will have quantifiable statistical completeness. Even a null result will help us understand the Fermi paradox, "why do we appear to be alone?"

Detecting an ETC signal is possible with current technology but requires a telescope and sensitive detector that can measure the planet's thermal flux and its reflected optical light, while distinguishing these from the star's scattered light and the terrestrial thermal noise background. Glare from the central star comes from the terrestrial atmosphere's distorting effect on the optical wavefront and from diffraction due to telescope optics. Suppressing this noise requires highly accurate adaptive optics (AO) and a coronagraph system. These requirements are implemented in the Colossus design.

With the Colossus telescope, which Kuhn says can be built in five years with sufficient funding, we will be able to see advanced civilization heat pattern as can be seen in night lights on the Earth from space.



SOURCE  IfA Maui, The Colossus Corporation

By 33rd Square

Subscribe to 33rd Square

 Fermi Paradox

At a recent TEDx event, Anders Sandberg energetically discussed the Fermi Paradox, which questions why we cannot see evidence of alien life or intelligence given our own situation on earth and the billions of potential worlds for life to arise. He also touches on what this may represent for the future of humanity.

Anders Sandberg's research centres on societal and ethical issues surrounding human enhancement and new technology, as well as on assessing the capabilities and underlying science of future technologies. His recent contributions include work on cognitive enhancement (methods, impacts, and policy analysis); a technical roadmap on whole brain emulation; on neuroethics; and on global existential risks, particularly on the question of how to take into account the subjective uncertainty in risk estimates of low-likelihood, high-consequence risk.

Sandberg explores the long term, and how much change in the universe can a civilization possibly cause?

Sandberg is James Martin Research Fellow at the Future of Humanity Institute at Oxford University, as well as associated with the Oxford Neuroethics Centre, the Uehiro Centre for Practical Ethics and the Programme on the Impacts of Future Technology.

Sandberg's diverse interests also extend to the far reaches of outer space.  At a recent TEDx event, he energetically discussed the Fermi Paradox, which questions why we cannot see evidence of alien life or intelligence given our own situation on earth and the billions of potential worlds for life to arise.  He also touches on what this may represent for the future of humanity.



SOURCE  TEDx Talks

By 33rd Square

Subscribe to 33rd Square