I want to revisit the paper on KIC 8462852 briefly this morning, as I’m increasingly fascinated with the astrophysics we’re digging into here. The fact that the star, some 1480 light years away, is also a candidate for further SETI investigation makes it all the more intriguing, but all my defaults lean toward natural processes, if highly interesting ones. Let’s think some more about what we could be looking at and why the ‘cometary’ hypothesis seems strongest. Remember that we’re looking at KIC 8462852 not only because the Kepler instrument took the relevant data, but because the Kepler team took advantage of crowdsourcing to create Planet Hunters, where interested parties could sign up to study the light curves of distant stars on their home computers. KIC 8462852 has been causing ripples since 2011 because while we do seem to be seeing something passing between its light and us, that something is not a planet but a large number of objects in motion around the star. Some of the...

Dysonian SETI operates under the assumption that our search for extraterrestrial civilizations should not stop with radio waves and laser communications. A sufficiently advanced civilization might be visible to us without ever intending to establish a dialogue, observed through its activities around its parent star or within its galaxy. Find an anomalous object difficult to explain through conventional causes and you have a candidate for much closer examination. Is KIC 8462852 such a star? Writing for The Atlantic, Ross Andersen took a look at the possibilities yesterday (see The Most Mysterious Star in Our Galaxy), noting that this F3-class star puts out a light curve indicating not a planetary transit or two, but a disk of debris. That wouldn't be cause for particular interest, as we've found numerous debris disks around young stars, but by at least one standard KIC 8462852 doesn't appear to be young. In a paper on this work, Tabetha Boyajian, a Yale University postdoc, and...

We often conceive of SETI scenarios in which Earth scientists pick up a beacon-like signal from another star, obviously intended to arouse our attention and provide information. But numerous other possibilities exist. Might we, for example, pick up signs of another civilization's activities, perhaps through intercepting electromagnetic traffic, or their equivalent of planetary radars? Even more interesting, as Brian McConnell speculates below, is the idea of listening in on a galactic network that contains information not just from one civilization but many. As Centauri Dreams readers know, McConnell and Alex Tolley have been developing the 'spacecoach' concept of interplanetary travel, discussed in the just published A Design for a Reusable Water-Based Spacecraft Known as the Spacecoach (Springer, 2015). It's a shrewd and workable way to get us deep into the Solar System. Today McConnell turns his attention to a SETI network whose detection could offer a big payoff for a young...

We've long discussed intercepting not only beacons but stray radio traffic from other civilizations. The latter may be an all but impossible catch for our technology, but there is a third possibility: Perhaps we can intercept the 'leakage' from a beamed power infrastructure used to accelerate another civilization's spacecraft. The idea has been recently quantified in the literature, and Jim Benford examines it here in light of a power-beaming infrastructure he has studied in detail on the interplanetary level. The CEO of Microwave Sciences, Benford is a frequent contributor to these pages and an always welcome voice on issues of SETI and its controversial cousin METI (Messaging to Extraterrestrial Intelligence). by James Benford Beaming of power to accelerate sails for a variety of missions has been a frequent topic on this site. It has long been pointed out that beaming of power for interplanetary commerce has many advantages. Beaming power for space transportation purposes can...

I have no idea whether we would be able to recognize a Kardashev Type III civilization if we saw one, but the search is necessary as we rule out some possibilities and examine others. As we saw yesterday, the Glimpsing Heat from Alien Technologies project at Penn State has examined data on 100,000 galaxies, finding 93 with mid-infrared readings that merit further study. One thing that we, operating with what we know about physics, would expect from a super-civilization is the production of waste heat, in the temperature range between 100 and 600 K, and that’s why previous searches for Dyson spheres have gone looking for such signatures. But Kardashev Type III is an extreme reach. We’re talking about a civilization capable of using the energies not just of its own star but of its entire galaxy, and just how this would be done is a question about which we can only speculate. As Erik Zackrisson (Uppsala University) and colleagues do in a new paper that balances nicely against Michael...

‘Dysonian SETI’ is all about studying astronomical data in search of evidence of advanced civilizations. As such, it significantly extends the SETI paradigm both backwards and forwards in time. It moves forward because it offers entirely new search space in not just our own galaxy but galaxies throughout the visible universe. But it also moves backward in the sense that we can use vast amounts of stored observational data from telescopes both ground- and space-based to do the work. We don’t always need new instruments to do SETI, or even new observations. With Dysonian SETI, we can do a deep dive into our increasingly abundant digital holdings. At Penn State, Jason Wright and colleagues Matthew Povich and Steinn Sigurðsson have been conducting the Glimpsing Heat from Alien Technologies (G-HAT) project, which scans data in the infrared from the Wide-field Infrared Survey Explorer (WISE) mission and the Spitzer Space Telescope. This is ground-breaking work that I’ve written about here...