Recent activity in sending signals to the stars has caught the attention of plasma physicist Jim Benford. The CEO of Microwave Sciences and chairman of the Sail Subcommittee for Breakthrough Starshot, Jim has more than a few doubts about the efficacy of these signals, and questions the rush to send them. Is the recent EISCAT signal detectable at interstellar distances? A look at the science of such signals follows, and thoughts on the caution with which we ought to proceed. By James Benford Yet another 'Message' Recently, advocates of METI (Messaging to Extraterrestrials) sent a 'message' consisting of prime numbers followed by 36 music pieces to Luyten's Star. It was a collaboration of METI International, led by Doug Vakoch, with the Catalonia Institute of Space Studies. This star is 12.4 light years from Earth and has a potentially habitable exoplanet (GJ 273b). This was sent from the EISCAT facilities near Tromsø, Norway, using a microwave antenna. The music pieces are 10 seconds...

It being the day after the Thanksgiving holiday here in the States, I hadn't planned a post, but a few more things have cropped up about 'Oumuamua that I can quickly tuck in here. Now that I've learned how to pronounce it (oh MOO-uh MOO-uh), it doesn't seem nearly as intimidating -- it's the lineup of vowels that trips up the unwary. On the other hand, Jim Benford suggested on Wednesday that we avoid the vowels altogether and call this thing 'the Shard.' Here's the photo Jim sent of the Shard, a 95-story London skyscraper sometimes called The Shard of Glass. It's 309.7 metres high, the tallest building in the United Kingdom, featuring 11,000 panes of glass with a total surface area of 56,000 square metres. What draws Jim's attention is the 6 to 1 aspect ratio, with 'Oumuamua's thought to be 10 to 1. Jim might also have referenced London's BT Tower (8 to 1), but what the Guinness Book of World Records calls the "most slender tower" turns out to be the i360 observation tower in...

The buzz about `Oumuamua, our first known visitor from another stellar system, seems likely to continue given yesterday's news that the object's axis ratio is a startling 10 to 1. Given all that, Jim Benford wondered whether there were SETI implications here. Was anyone on the case from our major SETI organizations? The answer is below, as we learn that the effort is ongoing. A frequent contributor to these pages, Jim is President of Microwave Sciences in Lafayette, California, which deals with high power microwave systems from conceptual designs to hardware. He also heads up the critical sail subcommittee for Breakthrough Starshot, the effort to send small beamed sails with miniaturized payloads to a nearby star. By James Benford I contacted Jill Tarter and Andrew Siemion about whether SETI researchers are conducting observations of the interstellar interloper, Oumuamua. Both say yes. Jill said that the Allen Telescope Array has been looking at it for a while. Andrew said that...

We've learned a great deal about comet 67P Churyumov-Gerasimenko thanks to the European Space Agency's Rosetta mission. What stands out to me is the fact that 40 percent of the comet, in terms of mass, is made up of organic compounds -- combinations of hydrogen, carbon, oxygen and nitrogen. These 'building blocks' of life on Earth are readily available and could have been delivered over and over again through our planet's long impact history. But where did the organic compounds themselves come from? Jean-Loup Bertaux (CNRS / UPMC / Université de Versailles Saint-Quentin-en-Yvelines), working with Rosine Lallement (Observatoire de Paris / CNRS / Université Paris Diderot), has put forth the idea that the organics formed in interstellar space long before the formation of the Solar System. The idea no longer seems as startling as it once might have, thanks to our continuing study of what are called diffuse interstellar bands, or DIBs. Revealed by spectroscopic studies,...

The SETI Institute's Laser SETI campaign made it past the finish line. Many thanks to the many Centauri Dreams readers who helped to make this happen. All sky, all the time SETI should produce astrophysical discoveries we haven't imagined, and of course we'll keep hoping for that intriguing transient that turns out to point to extraterrestrial intelligence. Exciting times ahead!

I've been thinking about SETI all weekend, not only because I'm pulling material together for the Tennessee Valley Interstellar Workshop in October, but also because I've been keeping an eye on the Laser SETI campaign now running on Indiegogo. With five days to go, Laser SETI is four-fifths of the way to its goal. When I think about the effort in the context of SETI's history, its significance becomes ever more clear. Please give this campaign a look and help if you can. The context I'm talking about relates to how we do SETI in a tight budgetary environment. Although it is not involved today, NASA was once a player in early studies, funding the work that produced the proposal for Project Cyclops, an enormous radio telescope array that was never built, although the ensuing report, Project Cyclops: A Design Study of a System for Detecting Extraterrestrial Intelligent Life, had influence throughout the young SETI community. But SETI has always been controversial in some quarters, and...

Although Titan is often cited as resembling the early Earth, the differences are striking. Temperature is the most obvious, with an average of 95 Kelvin (-178 degrees Celsius), keeping water at the surface firmly frozen. Our planet was tectonically active in its infancy, roiled not only by widespread volcanism but also asteroid impacts, especially during the period known as the Late Heavy Bombardment some 4.1 to 3.8 billion years ago. Throw in the fact that the Earth had high concentrations of carbon dioxide -- Titan does not -- and it's clear that we can't make too broad a comparison between the two worlds. What we do have on Titan, however, is an atmosphere that teems with chemical activity, fueled by light from the Sun and the charged particle environment in the moon's orbit around Saturn. So we do have a chemistry here that is capable of turning simple organics into more complex ones. Thus the findings from a new study of archival data using the Atacama Large...

Yesterday's post dwelt on an article by Steven Johnson in the New York Times Magazine that looked at the issue of broadcasting directed messages to the stars. The article attempted a balanced look, contrasting the goals of METI-oriented researchers like Douglas Vakoch with the concerns of METI opponents like David Brin, and fleshing out the issues through conversations with Frank Drake and anthropologist Kathryn Denning. Johnson's treatment of the issue prompted a response from a number of METI critics, as seen below. The authors, all of them prominent in SETI/METI issues for many years, are listed at the end of the text. We thank Steven Johnson for his thoughtful New York Times Magazine article, which makes it clear that there are two sides to the METI issue. We applaud his idea that humankind needs a mechanism for decision-making on long-term issues that could threaten our future. As Johnson implies, deliberately calling ourselves to the attention of a technological civilization...

If we were to send a message to an extraterrestrial civilization and make contact, should we assume it would be significantly more advanced than us? The odds say yes, and the thinking goes like this: We are young enough that we have only been using radio for a century or so. How likely is it that we would reach a civilization that has been using such technologies for an even shorter period of time? As assumptions go, this one seems sensible enough. But let's follow it up. In an interesting piece in the New York Times Magazine, Steven Johnson makes the case this way: Given the age of the universe, almost 14 billion years, that means it would have taken 13,999,999,900 years before radio communications became a factor here on Earth. Now let's imagine a civilization that deviates from our own timeline of development by just one tenth of one percent. If they are more advanced than us, they will have been using technologies like radio and its successors for 14 million years. Assumptions...

Yesterday I made mention of the Schwartz and Townes paper "Interstellar and Interplanetary Communication by Optical Masers," which ran in Nature in 1961 (Vol. 190, Issue 4772, pp. 205-208). Whereas the famous Cocconi and Morrison paper that kicked off radio SETI quickly spawned an active search in the form of Project Ozma, optical SETI was much slower to develop. The first search I can find is a Russian project called MANIA, in the hands of V. F. Shvartsman and G. M. Beskin, who searched about 100 objects in the early 1970s, finding no significant brightness variations within the parameters of their search. If you want to track this one down, you'll need a good academic library, as it appears in the conference proceedings for the Third Decennial US-USSR Conference on SETI, published in 1993. Another Shvartsman investigation under the MANIA rubric occurred in 1978. Optical SETI did not seem to seize the public's imagination, perhaps partially because of the novelty of communications...

The Laser SETI campaign we looked at on Friday is one aspect of a search for intelligent life in the universe that is being addressed in many ways. In addition to optical methods, we look of course at radio wavelengths, and as we begin to characterize the atmospheres of rocky exoplanets, we'll also look for signs of atmospheric modification that could indicate industrial activity. But we have to be careful. Because SETI looks for evidence of alien technology, it is a search for civilizations about whose possible activities we know absolutely nothing. So we can't make assumptions that might blind us to a detection. Getting the blinders off also means extending our reach. If successful, the Laser SETI project will do two things we haven't been able to do before -- it will scan the entire sky and, because it is always on, it will catch optical transients we are missing today, and tell us whether any of these are repeating. In radio terms, think of the famous WOW! signal of 1977,...

The SETI Institute's just announced Laser SETI funding campaign intends to put into practice what SETI researchers have been anticipating for decades, an all-sky, all-the-time observing campaign. The Institute's Eliot Gillum and Gerry Harp are behind the project, backed by an impressive list of advisors, with the intention of using optical SETI methods to look for signs of extraterrestrial civilizations. In doing so, they're reminding us how we've done SETI, how we can surmount its current limitations, and what a SETI of the future will look like. Think about how SETI has evolved since the days when Frank Drake created Project Ozma at the National Radio Astronomy Observatory at Green Bank (WV). Fresh with the insights of Giuseppe Cocconi and Philip Morrison, who examined radio methods and suggested a search for signals near the 21 centimeter wavelength of neutral hydrogen, Drake turned a 26-meter radio telescope to examine the nearby Sun-like stars Tau Ceti and Epsilon Eridani. Would...

I came across the work of Chin-Fei Lee (Academia Sinica Institute of Astronomy and Astrophysics, Taiwan) when I had just read Avi Loeb's essay Cosmic Modesty. Loeb (Harvard University) is a well known astronomer, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics and a key player in Breakthrough Starshot. His 'cosmic modesty' implies we should accept the idea that humans are not intrinsically special. Indeed, given that the only planet we know that hosts life has both intelligent and primitive lifeforms on it, we should search widely, and not just around stars like our Sun. More on that in a moment, because I want to intertwine Loeb's thoughts with recent work by Chin-Fei Lee, whose team has used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect organic molecules in an accretion disk around a young protostar. The star in question is Herbig-Haro (HH) 212, an infant system (about 40,000 years old) in Orion about 1300...

400 light years away in a star-forming region called Rho Ophiuchi there is an interesting stellar system in the making. Catalogued as IRAS 16293-2422, what we have here is a triple protostar system -- a binary separated by 47 AU and a third star at 750 AU. All three have masses similar to the Sun, and while the system is young, it has already achieved a certain fame in that researchers working with data from the Atacama Large Millimeter Array have been able to identify a simple form of sugar called glycolaldehyde in surrounding gas. Learning that building blocks of life can form in other systems is useful, but here we have sugar in the region where a protoplanetary disk can form, an indication that such materials are widely available in the places where planets begin to coalesce around their host star. Then just this month we've learned that further ALMA work has yielded the prebiotic organic molecule methyl isocyanate (CH3NCO) in the same system. Niels Ligterink (Leiden Observatory)...

Twitter action has been fast and furious with this morning's news of the first clear dip in light from Boyajian's Star (KIC 8462852) since the Kepler data. #TabbysStar IS DIPPING! OBSERVE!! @NASAKepler @LCO_Global @keckobservatory @AAVSO @nexssinfo @NASA @NASAHubble @Astro_Wright @BerkeleySETI— Tabetha Boyajian (@tsboyajian) May 19, 2017 I'm on the road most of today and so couldn't get off a full post, but I did want to pass along Tabetha Boyajian's newsletter, short but sweet. Hello all, We have detected a dip in progress! Not much time to share details - we are working hard coordinating followup observations. Here is a snapshot of LCO data for the Month of May. Stay tuned! ~Tabby et al. And here is Jason Wright's video chat on this event during his visit to UC Berkeley. https://www.youtube.com/watch?v=eYpIGZS8nJc&w=500&h=416

We’ve been talking about the Colossus project, and the possibility that this huge (though remarkably lightweight) instrument could detect the waste heat of extraterrestrial civilizations. But what are the chances of this, if we work out the numbers based on the calculations the Colossus team is working with? After all, Frank Drake put together his famous equation as a way of making back-of-the-envelope estimates of SETI’s chances for success, working the numbers even though most of them at that time had to be no more than guesses. Bear in mind as we talk about this that we’d like to arrive at a figure for the survival of a civilization, a useful calculation because we have no idea whether technology-driven cultures survive or destroy themselves. Civilizations may live forever, or they may die out relatively quickly, perhaps on a scale of thousands of years. Here Colossus can give us useful information. The intention, as discussed in a paper by Jeff Kuhn and Svetlana Berdyugina that...

Yesterday we looked at the PLANETS telescope, now under construction on the Haleakala volcano on the island of Maui. What will become the world's largest off-axis telescope is considered a pathfinder, part of the progression of instruments that will take us through the array of sixteen 5-meter mirrors that will be called ExoLife Finder, itself to be followed by Colossus, an instrument comprised of 58 independent off-axis telescopes. Colossus will use ultra-thin mirror technologies and interferometric methods to achieve an effective resolution of 74 meters. And it will be optimized for detecting extrasolar life and extraterrestrial civilizations. Image: Artist's rendering of the Colossus telescope. Credit: Colossus/Dynamic Structures Ltd. How to build something on such a scale? The design work is being handled by a consortium led by Jeff Kuhn (University of Hawaii), Svetlana V. Berdyugina (University of Hawaii/Kiepenheuer Institut für Sonnenphysik), David Halliday (Dynamic Structures)...

Andrew Siemion (Berkeley SETI Research Center) presented results from the first year of the Breakthrough Listen initiative last Thursday at the Breakthrough Discuss meetings in Palo Alto. The data can be acquired here, with the caveat that file sizes can be gigantic and the data formats demand specialized software. Background information and details are available on this BSRC page. Working with the Parkes instrument in New South Wales as well as the Green Bank telescope in West Virginia and Lick Observatory's Automated Planet Finder on Mt. Hamilton in California, the project is rapidly amassing petabytes of data. Image: The largest single-dish fully steerable radio telescope began operation in 2000 August in Green Bank, West Virginia, USA. Dedicated as the Robert C. Byrd Green Bank Telescope, the device weighs over 30 times more than the Statue of Liberty, and yet can point anywhere in the sky more precisely than one thousandth of a degree. The main dish is so large that it could...

About 370 light years away in the constellation Centaurus is a variable star whose spectrum continues to raise eyebrows. The star is laced with oddball elements like europium, gadolinium, terbium and holmium. Moreover, while iron and nickel appear in unusually low abundances, we get short-lived ultra-heavy elements, actinides like actinium, plutonium, americium and einsteinium. Hence the mystery: How can such short-lived elements persist in the atmosphere of a star? Discovered in 1961 by the Polish-American astronomer Antoni Przybylski, these traits have firmly placed Przybylski's Star in the Ap class of chemically peculiar stars. Its very name is a cause of continuing conversation. PRZYBYLSKI'S STAR (HD 101065) Blue dwarf with a peculiar spectrum showing an almost complete absence of vowels.— FSVO (@FSVO) November 22, 2012 Well, true enough. If Przybylski's Star is a challenge to understand, it's also a challenge to pronounce. Charles Cowley (University of Michigan), who...

We have a lot to learn about Fast Radio Bursts (FRBs), a reminder that the first of these, the so-called Lorimer Burst (FRB 010724) was detected only a decade ago. Since then we've found 16 others, all thought to be at cosmological distances. The 2015 detection of FRB 150418, at first thought to have left an afterglow, has now been traced to an active galactic nucleus powered by a supermassive black hole. FRB 121102 appears to be a rare case of a repeating FRB (about which more a bit later). The distances involved and the brightness of the FRBs have led to source hypotheses ranging from gamma ray bursts to massive neutron stars. But as Avi Loeb (Harvard University) speculates in a new paper slated to appear in Astrophysical Journal Letters, we could conceivably be dealing with an engineering phenomenon rather than a natural one. What Loeb and Manasvi Lingam, a Harvard postdoctoral fellow at Harvard's School of Engineering, discuss is whether FRBs could be interpreted as artificial...