Astronomers look at one patch of sky and see no signs of alien life

Worlds without end: Using an Australian radio telescope array focused in the FM frequencies, astronomers did a seventeen hour sweep of one small of sky and found no evidence of alien transmissions.

“We observed the sky around the constellation of Vela for 17 hours, looking more than 100 times broader and deeper than ever before. With this dataset, we found no technosignatures—no sign of intelligent life.”

Professor Tingay said even though this was the broadest search yet, he was not shocked by the result. “As Douglas Adams noted in The Hitchhikers Guide to the Galaxy, ‘space is big, really big’. … And even though this was a really big study, the amount of space we looked at was the equivalent of trying to find something in the Earth’s oceans but only searching a volume of water equivalent to a large backyard swimming pool.

The radio array used in this search is only a small precursor to a much larger array, dubbed the Square Kilometer Array (SKA), which is under construction and many times more sensitive.

More data says no alien civilization at KIC 8462852

New observations of the star KIC 8462852 to see if an alien civilization had produced laser signals has produced a null result, reinforcing the conclusion that the erratic dimming of the star is not caused by alien megastructures.

On six nights between October 29 and November 28, 2015, scientists searched for pulses as short as a billionth of a second at the Boquete Optical SETI Observatory in Panama, using a 0.5 m Newtonian telescope. The observatory’s relatively small telescope uses a unique detection method having enhanced sensitivity to pulsed signals. If any hypothetical extraterrestrials had beamed intentional laser pulses in the visible spectrum toward Earth, the Boquete observatory could have detected them so long as they exceeded the observatory’s minimum detectable limit.

KIC 8462852 has puzzled astronomers because it shows irregular dimming unlike anything seen for another star. The anomalous light curve was measured using NASA’s Kepler telescope, as part of its search for exoplanets. However, even though a planet the size of Jupiter would cause dimming of approximately 1%, the dimming observed for KIC 8462852 was far greater – up to 22%. Just as strange, the dimming didn’t follow the regular pattern of a planet orbiting a star, but instead was unpredictable. The best explanation to date is that the dimming may have been caused by cometary fragments in a highly elliptical orbit around KIC 8462852, intercepting starlight at the same time the Kepler mission was observing it.

Astronomers find no evidence of nearby alien civilizations

New observations of the best candidate galaxies now suggests that very advanced civilizations are very rare or don’t exist in the local universe.

They looked at several hundred nearby galaxies that emitted a high amount of mid-infrared radiation, which could possibly be produced as the waste heat from civilizations using energy on galactic scales.

Professor Michael Garrett (ASTRON & University of Leiden) has used radio measurements of the very best candidate galaxies and discovered that the vast majority of these systems present emission that is best explained by natural astrophysical processes. In particular, the galaxies as a sample, follow a well-known global relation that holds for almost all galaxies – the so-called “Mid-Infrared Radio correlation”. The presence of radio emission at the levels expected from the correlation, suggests that the mid-IR emission is not heat from alien factories but more likely emission from dust – for example, dust generated and heated by regions of massive star formation.
As Professor Garrett explains: “the original research at Penn State has already told us that such systems are very rare but the new analysis suggests that this is probably an understatement, and that advanced Kardashev Type III civilisations basically don’t exist in the local Universe. In my view, it means we can all sleep safely in our beds tonight – an alien invasion doesn’t seem at all likely!”.

Joking aside, Professor Garrett is still looking at a few candidate galaxies that lie off of the astrophysical correlation: “Some of these systems definitely demand further investigation but those already studied in detail turn out to have a natural astrophysical explanation too. It’s very likely that the remaining systems also fall into this category but of course it’s worth checking just in case!”

Obviously, the uncertainty of these results is quite high. Nonetheless, the results indicate that either humanity really is the only intelligent species in this part of the universe, or advanced civilizations are far more efficient in their use of energy than is reasonable to assume.

Organic material from Mars?

The uncertainty of science: Scientists theorize that the carbon material found in a 2011 meteorite could be Martian biological material.

Ejected from Mars after an asteroid crashed on its surface, the meteorite, named Tissint, fell on the Moroccan desert on July 18, 2011, in view of several eyewitnesses. Upon examination, the alien rock was found to have small fissures that were filled with carbon-containing matter. Several research teams have already shown that this component is organic in nature. But they are still debating where the carbon came from.

Chemical, microscopic and isotope analysis of the carbon material led the researchers to several possible explanations of its origin. They established characteristics that unequivocally excluded a terrestrial origin, and showed that the carbon content were deposited in the Tissint’s fissures before it left Mars.

One scientist’s modeling of the early universe suggests to him that intelligent life could have evolved as early as 15 million years after the Big Bang.

Theories! One scientist’s modeling of the early universe suggests to him that intelligent life could have evolved as early as 15 million years after the Big Bang.

This is fun stuff, but entirely theoretical and not to be taken very seriously. We know with certainty as much about the early universe as a mouse understands Shakespeare. To predict accurately the nature or even existence of life at that time is stretching our knowledge considerably.

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.