Tag Archives: SETI

Aggressive SETI observations of Tabby’s star upcoming

Breakthrough Listen, an effort to listen for radio signals from alien civilizations that, plans to devote significant time this year observing Tabby’s star to see if an alien mega-structures are causing that star’s unexplained dimming.

While Siemion and his colleagues are skeptical that the star’s unique behavior is a sign of an advanced civilization, they can’t not take a look. They’ve teamed up with UC Berkeley visiting astronomer Jason Wright and Tabetha Boyajian, the assistant professor of physics and astronomy at Louisiana State University for whom the star is named, to observe the star with state-of-the-art instruments the Breakthrough Listen team recently mounted on the 100-meter telescope. Wright is at the Center for Exoplanets and Habitable Worlds at Pennsylvania State University.

The observations are scheduled for eight hours per night for three nights over the next two months, starting Wednesday evening, Oct. 26. Siemion, Wright and Boyajian are traveling to the Green Bank Observatory in rural West Virginia to start the observations, and expect to gather around 1 petabyte of data over hundreds of millions of individual radio channels.

New analysis says it ain’t aliens at strange star

The uncertainty of science: A new analysis of old star data has concluded that KIC 8462852, also known Tabby’s Star and subject to random fluctuations that no scientist can explain, has not dimmed by 20% in the past century.

This reduces the chances that the fluctuations are caused by the slow accumulating construction of a Dyson sphere by an alien civilization, as some have proposed, but it still does nothing to explain the star’s random changes in brightness.

Honing the search for alien civilizations

Worlds without end: In order to increase the odds of contacting extraterrestrial civilizations, astronomers have calculated the area in the sky where an alien-built Kepler could have seen the Earth transit the sun, thus increasing the chances that those alien-astronomers have discovered Earth and have tried to contact us.

“The key point of this strategy is that it confines the search area to a very small part of the sky. As a consequence, it might take us less than a human life span to find out whether or not there are extraterrestrial astronomers who have found the Earth. They may have detected Earth’s biogenic atmosphere and started to contact whoever is home,” explains René Heller from the MPS.

Not every star is equally well suited as a home of extraterrestrial life. The more massive a star, the shorter is its life span. Yet, a long stellar life is considered a prerequisite for the development of higher life forms. Therefore the researchers compiled a list of stars that are not only in the advantageous part of the sky but also offer good chances of hosting evolved forms of life, that is, intelligent life. The researchers compiled a list of 82 nearby Sun-like stars that satisfy their criteria. This catalogue can now serve as an immediate target list for SETI initiatives.

Was the Wow! signal from two comets?

One of the most baffling radio astronomical detections, dubbed the “Wow! signal” and that some believe could have been caused by an extraterrestrial transmission, is now theorized to have been caused by two comets, not an alien civilization.

Antonio Paris, a professor of astronomy at St Petersburg College in Florida, thinks the signal might have come from one or more passing comets. He points the finger at two suspects, called 266P/Christensen and P/2008 Y2 (Gibbs). “I came across the idea when I was in my car driving and wondered if a planetary body, moving fast enough, could be the source,” he says.

Comets release a lot of hydrogen as they swing around the sun. This happens because ultraviolet light breaks up their frozen water, creating a cloud of the gas extending millions of kilometres out from the comet itself. If the comets were passing in front of the Big Ear in 1977, they would have generated an apparently short-lived signal, as the telescope (now dismantled) had a fixed field of view. Searching that same area – as subsequent radio telescopes did – wouldn’t show anything. Tracing the comets’ positions back in time, Paris says that the possible origin for the Wow! signal falls right between where they would have been.

Neither comet was known in 1977; they were both discovered in the last decade, which would mean nobody would have thought to search for them.

No sign of alien civilization at distant star

The uncertainty of science: Two weeks of targeted observations by the Allen Telescope Array in California have detected no clear signal of an alien civilization at the star KIC 8462852 where Kepler observations have seen variations that could possibly be caused by giant alien structures.

Two different types of radio signals were sought: (1) Narrow-band signals, of order 1 Hz in width, such as would be generated as a “hailing signal” for societies wishing to announce their presence. This is the type of signal most frequently looked for by radio SETI experiments.  (2) Broad-band signals that might be due to beamed propulsion within this star system.  If astroengineering projects are really underway in the vicinity of KIC 8462852, one might reasonably expect the presence of spacecraft to service this activity.  If these craft are propelled by intense microwave beams, some of that energy might manifest itself as broad-band radio leakage. “This is the first time we’ve used the Allen Telescope Array to look for relatively wide-band signals, a type of emission that is generally not considered in SETI searches,” said SETI Institute scientist Gerry Harp.

Analysis of the Array data show no clear evidence for either type of signal between the frequencies of 1 and 10 GHz.  This rules out omnidirectional transmitters of approximately 100 times today’s total terrestrial energy usage in the case of the narrow-band signals, and ten million times that usage for broad band emissions.

The data shows no sign of alien civilization, but it also does not eliminate the possibility. More detailed observations are required to do that.

Internet tycoon commits $100 million to alien life search

Russian internet entrepreneur Yuri Milner has given SETI $100 million for a ten year project to accelerate their effort to search for evidence of extraterrestrial life.

Understanding why SETI needs private funding is important:

SETI has been going on since 1960, when radio telescopes became sensitive enough to detect signals from another planet if it was broadcasting signals similar to those which our civilization does. Researchers developed devices that could monitor millions of frequencies at once for any signal that looked at all different from that produced by astronomical objects or the natural background. At first funded by universities and NASA, public funding for SETI was axed by Congress in the early 1990s. Since then, the nonprofit SETI League has received funding of a few million dollars a year from private donors.

Congress correctly cut the funds because it isn’t really the business of the federal government to search for alien life. Some taxpayers really don’t want their money used for that purpose, and they should have the right to say no. Instead, Congress essentially told SETI to do it right: Get private funding from people who want the research done. The work will be done more efficiently for less, and no one will be required to contribute who doesn’t want to.

Milner’s contribution now is the biggest donation yet, and suggests that interest in this research is building culturally.

“Vulcan” and “Cerberus” win the poll to name Pluto’s two unnamed moons.

“Vulcan” and “Cerberus” win the poll to name Pluto’s two unnamed moons. Key quote:

Vulcan was a late addition to the Pluto moon name contenders, and pulled into the lead after Shatner, building on his Capt. James T. Kirk persona, plugged the name on Twitter. Vulcan, the home planet of Kirk’s alien-human hybrid first officer Spock, is not just a fictional world in the Star Trek universe. It is also the name of the god of fire in Roman mythology, and officials at SETI added the sci-fi favorite to the ballot for that reason.

A targeted SETI observation of Gliese 581, the nearest star with exoplanets in the habitable zone, has found no evidence of alien communications.

Radio silence: A targeted SETI observation of Gliese 581, the nearest star with exoplanets in the habitable zone, has found no evidence of alien communications.

This was a proof of concept experiment, and though they detected nothing, they also did not rule out the possibility of alien life, as their radio telescope wasn’t sensitive enough to do so. You can download the actual paper here.

From Kepler: Dozens of Earths in the habitable zone

At a press conference today the science team at Kepler announced a swath of new discoveries from the space telescope, all of which point to the impending discovery of multiple Earth-like planets capable of harboring life.
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