For better or worse, self-driving vehicles are the future. It will be a rather messy future full of media scare articles painting self-driving vehicles as unsafe, fully legitimate concerns about sending thousands of commercial drivers to the unemployment line, and varying rejection from consumers on grounds of distrusting technology and a preference to be at the wheel themselves, but it is the future nonetheless. I'm not yet sure how I feel about that, I can see both sides of the argument for and against self-driving vehicles,  but what I do know is that the benefits and cost savings are just so for commercial use that self-driving vehicles will be ubiquitous within a decade.

The world's first self-driving beer run

Breaking News: Have We Detected 234 Alien Civilizations?

By John Michael Godier

Several days ago a paper came out that made an interesting claim. That claim was that anomalous signals from 234 stars in the Milky Way of types similar to our sun were emitting pulsed, regular signals consistent with what you would expect from alien civilizations employing laser communications.

While the media at large loves to take stories like this and sensationalize them and make all sorts of clickbait headlines that lead people to believe that aliens are discovered weekly, that's obviously not the case, and this particular paper is very preliminary but does still fall into the realm of possibility.

The paper authored by researchers Ermanno Borra and E. Trottier, details a study of the Sloan Digital Sky Survey that looked for periodic fluctuations in the spectra of stars in the galaxy that were abnormal but consistent with a pulsed signal from an alien civilization. They found abnormal signals coming from 234 different stars.

But, abnormal doesn't immediately mean alien so much study and work will be needed to determine exactly what's going on with these stars. I stress, this story is more about figuring out a new way to detect alien signals rather than actually making the claim to have detected them. Take this one with a grain of salt, that's probably not what these are. Extraordinary claims require extraordinary proof.

The whole thing goes back to an earlier paper that Borra authored in 2012. In it, Borra posits that it should be possible to detect pulsed laser signals from alien civilizations mixed within the natural spectra of the stars that their homeworlds orbit.

Borra backs this up by pointing out that our current technology could produce such signals that would be detectable by other species if they were looking, using these same methods. That's if we made the effort to try to contact other races. We currently are not.  

Now, what is a spectrum? Think of it like this; stars have a sort of fingerprint made of light that reveals information about them. At its most basic level, it's simply using a prism to split light into its constituent rainbow spectrum and looking for dark lines that appear in the spectrum. These lines, called Fraunhofer lines, are caused by certain materials present in the star that absorb different frequencies of light. This yields information about the star's chemical makeup.

But you can tell much more from how those lines are arranged and shifted, such as if the star is moving towards you or away from you, of even if obscuring dips in the light are due to diffuse dust and gas or gigantic alien megastructures as what everyone's waiting for with KIC 8462852, and many other things.

And, luckily, astronomers have taken lots of spectra over the years while studying stars. A lot to the tune of huge sky surveys such as the Sloan survey which detail the spectra of at least 2.5 million stars at this point. Borra argued in 2012 that you could search those existing spectra for signs of alien civilizations using pretty straightforward methods.

Fast forward to today. Borra and Trottier did just that and out of the 2.5 million spectra they found 234 anomalous ones that could fit the bill for alien communications. That's a pretty tiny percentage, perhaps what you might expect given that intelligent alien life is probably pretty rare, but we don't really know.

But what was interesting about those spectrums is that the associated stars just happened to be overwhelmingly sun-like, meaning that the stars were of sufficient age and stability to reasonably say that it's possible for them to have civilizations developing around them based on the conditions of our own solar system and our development. Interesting results to be sure.

But, and the authors are careful to point this out, it's just that. Interesting and worth checking out. These signals are very weak, and while the argument can be made that aliens need not transmit using huge amounts of energy just to say hello, stars themselves can be really enigmatic and naturally produce all manner of strange signals.

We've seen some strange stuff with stars before that ended up having fully natural explanations. Natural is always very much more likely than artificial. There's a lot of variation in how stars behave due to a mind-boggling array of chemical and physical factors that can be present within them, to the point that we often come across stars we don't quite understand. There are anomalous stars out there that are so bizarre that they shouldn't even exist. But they do, which means we just haven't thought of a way to explain them yet. That's likely to the be the case with these anomalous stars.

Further study is likely to show that most, if not all, of these 234 anomalies are of natural origin. But, then again, if NASA itself is to be believed, it's also probably likely that within just a few decades we will have discovered evidence of intelligent alien life and studying stellar spectra is just one more tool we can use to accomplish that.

An Eyebrow Raiser

I'm not against AI or its development, nor am I worried about it ... yet.

apple-employs-tech-guru-from-university-that-taught-computers-to-defeat-humans/

KIC 8462852 Tabby's Star Update 10/6/2016

This is another installment in my continuing coverage of KIC 8462852 or Tabby's star, easily the strangest star we've yet come across in our universe. Since my last update, a number of scientific papers have been published that offer a new group of potential explanations for the dimming phenomena, but the possibility of alien megastructures causing the dimming events at this star still has not been discounted.

For more solid science only back story on Tabby's star, check out the other videos on KIC 8462852 on this channel. They are arranged by date in the title, starting with the first one I did on April 10th of 2016 and together in sequence provide a complete overview of what we know and what we can reasonably speculate if indeed the dimming events at this star are of alien origin, which I stress is highly unlikely.

Most noteworthy is that there now seems to be a disparity of sorts in the story. There are two phenomena that seem to be going on at Tabby's star. The first is the major dimming events first detected by the Kepler Spacecraft that caught everyone's attention in the first place. The second, which if it exists is almost certainly related, is a long-term dimming trend first noted by Bradley Schaeffer who found that the star had dimmed significantly over the course of a century.

Schaeffer's work was called into question by a group led by Michael Hippke leading to somewhat of a public row between several scientists. Hippke essentially questioned Schaeffer's methodology and stated that he could find no evidence of this long-term dimming trend. Schaeffer had based his findings on one set of sky survey photographic plates taken over the course of a century. This wasn't the only set of plates of this kind, and Hippke used a second set known as the Sonneburg plates after the German observatory where they were taken and again found no evidence of a long-term dimming trend.

More, several other scientists published a paper calling the long-term dimming into question as well. They attributed the dimming at Tabby's Star to a gap in the data, but oddly found several other similar F-type stars in the survey that do appear to be experiencing similar long-term dimming trends of their own on a century scale. These are of unknown origin. There seems to be all sorts of mysteries buried in old sky surveys.

So is there a long-term dimming trend or not? Well, now a third group of scientists have entered the mix. Using the data from Kepler, Benjamin Montet and Joshua Simon have seemingly confirmed the long-term dimming trend over the period that Kepler was active, or at least a dimming trend during that period. So the pendulum tips in favor of the long-term dimming trend existing once more.

But that isn't the only news. Regarding the deep short-term dips that made this star famous, several new theories have emerged or reemerged regarding natural explanations that better fit the observations of this star than the previous explanations, including the alien megastructure possibility, which remains the least likely of any of the explanations but still remains on the table.

One interesting new theory was put forth by Valeri Makarov of the US Naval Observatory. This theory suggests that what we're seeing is basically some star's disembodied debris disk, perhaps tossed out into interstellar space by another gravity source, passing in front of our line of sight to Tabby's star but not actually related to it.

This seems to potentially be a good fit with what we see with the star. Such material, being in interstellar space, would be very cold. That would explain the lack of infra-red emissions that you would expect to see if the debris was orbiting KIC 8462852. It would also potentially explain both of the dimming trends, depending on how that cloud of debris was set up.

The only thing standing in the way of this explanation is weak evidence of some periodicity in the Kepler light curves. This suggests, but not very well, that whatever is causing the dimming is in orbit of the star. The only way to tell for sure is to check out Tabby's star over a long period of time to look for recurring periodic dips. The good news is that this is already happening, Tabitha Boyajian and her team have the funding and are observing the star actively. The bad news is that it could be several years before we know.  

Complicating this further are the problems with the long-term dimming trend. If it doesn't exist, then one of the older theories returns to the table, the idea that the dimming could be caused by a cloud of disintegrating comets in orbit of the star. The lack of infra-red emissions would be accounted for due to the comets being cold. But there are problems with this theory that make it not a perfect fit for what is observed.

Another group of scientists modeled the comet hypothesis. While a very large, and I mean huge, number of comets does fit with the later dimming events in the Kepler data, they could not model the day 800 long, slow, smooth event. This remains a mystery and has no easy explanation under any scenario and in some ways does serve to support the alien megastructure theory.

Another possibility is that the star is younger than we think it is and still has a disc of debris orbiting it coalescing into planets. This is also not a great fit due to the lack of infrared-emissions, but another theory suggests that if we're seeing that disc edge on, then that would account for the missing infrared.

And now to the megastructures. While highly unlikely, this is most probably a natural phenomenon, we can speculate about a few possibilities. While the Kepler light curves are consistent with a Dyson swarm, and potentially even a large baffle in space designed specifically to block light, see my earliest video for that story on that, the long-term dimming trend would suggest that we're seeing it under construction. Very rapid construction, so much so that it seems unlikely according to the Montet and Simon findings. Even self-replicating nano-technology might have trouble building something that quickly. If it is aliens, then why are they in such a hurry?

I think this speed works against the megastructure hypothesis and for the natural explanations. A passing cloud of debris could have areas of higher density that might block a star and cause a dimming trend on a scale of centuries. At some point it would go the opposite way and turn into a brightening trend. So once again, I must stress, that it is highly unlikely for multiple reasons that the mysteries of KIC 8462852 are of alien origin. But, it's still on the table. Only time will tell for sure as more observations of the star are made.

Colonizing and Terraforming Venus

While talk about colonizing the solar system has dominated the news lately with Elon Musk's visionary plan for Mars, another potential target for colonization might not be getting the attention it deserves. There are reasons for this, the planet's surface is a truly hellish mix of extremely hot temperatures and sulfuric acid. That planet is Venus, and while at first glance it doesn't look like a good candidate for colonization, there are some surprisingly attractive attributes to this world that may eventually make it worthwhile.

As Elon Musk points out, we need to become a multiple planet species if we wish the human race to survive any calamity that might cause our extinction such as an asteroid impact. Sooner or later, something bad will happen and a second planet would serve as insurance against extinction. But why not a third planet? And why not Venus?

If it weren't for the hostile surface conditions, Venus would be the obvious choice for colonization as opposed to Mars. Surface conditions aside, Venus could be called a sister planet to earth. With Mars, due to its smaller size, we aren't yet certain that humans will avoid bone decalcification due to a lack of gravity. This is not the case for Venus, which is almost the same size as earth with comparable gravity probably eliminating decalcification as a problem for colonization entirely.

Venus is also closer than Mars, which favors both transport and communications. Launch windows for Mars occur every 780 days as the planet passes close by. For Venus, this is only 584 days. Flight times are also going to be shorter than for Mars. Like Mars, Venus' atmosphere is mostly carbon dioxide. If you filter out the sulfuric acid, you can use that carbon dioxide to grow plants. And there is a zone on Venus that looks far more attractive than its surface.

This zone, which is about 31 miles in the atmosphere above the planet's surface, has a different composition due to the fact that nitrogen and oxygen are lighter than carbon dioxide. This means that if you fill a balloon with earth air, it will float in this region. The temperature here is nicer as well, about 75 °C or 167 degrees. If you go a bit higher, say 5 kilometers, it drops to a comfortable 81 degrees Fahrenheit. This zone also favors colonization in that it also happens to be about the same air pressure that we experience here on earth. Handy indeed. And, the atmosphere above this sweet spot naturally shields out cosmic radiation roughly comparable to how Earth's atmosphere does.

That's a lot of points in Venus' favor. But the obvious problem here is that you'd have to suspend your colony high up in the atmosphere of Venus and make sure it stays there. But this may not be as hard as you might think. As I mentioned, breathable earth air is a lifting gas on Venus, much like helium is here. That means that if you were inside a balloon on Venus, you could easily live, and so long as that balloon doesn't pop, you would be in much safer natural conditions than one would be on the surface of Mars.

If your balloon sprung a leak, for example, there would be no explosive decompression due to the similar air pressures inside and out. You would have plenty of time to patch it up. Similarly, you would not require pressurized space suits, just protective ones to keep out the sulfuric acid and of course a breathing apparatus and protection from the heat, which isn't that big of a deal.

Now, it's pretty windy up there, often reaching over 200 miles per hour, but there's also nothing to run into so you could let the balloon colony move with the winds, which would reduce structural stress.

There are cons to the idea of colonizing Venus as well. It has no oxygen, so it would have be manufactured from carbon dioxide. It also has basically no water, meaning you'd have to get that from the sulfuric acid. Retrieving anything from the surface would difficult given the surface conditions. And you would need some serious corrosion protection in all elements of your colony. Add that to the fact that Venus rotates very slowly compared to earth, its day is 243 earth days long. In fact, its day is longer than its year, which is only 224 earth days.

But if we did colonize Venus, might we be able to terraform it and make it earth-like? The answer is yes, it's theoretically possible. In fact, Paul Birch put forth just such a plan that would allow the planet to be terraformed in just two centuries. Humans have taken on huge projects that took even longer than that before, often it would take 500 years or more to build a medieval gothic cathedral. So two centuries is not that long of a time for a project.

Birch's plan envisions putting a thin solar shade perhaps made of Mylar or a similar substance in the line of sight between the sun and Venus and reduce the temperature of the atmosphere. As the planet cools, the high pressures will cause the carbon dioxide to liquefy and rain onto the planet as oceans. Then, as the cooling continues, the oceans freeze and become dry ice. You then cover the frozen oceans over with a thermally insulating layer and you've got a fresh planet to work with where the amount of carbon dioxide in the protoatmosphere can be controlled.

To make it earth-like, you would first need a lot of water. The problem there is that water is hard to transport, so it's better to make it onsite. To do this, you need hydrogen, which is something Venus doesn't have much of. But the gas giant planets do and it's possible to mine it from them.

Transporting that hydrogen could be accomplished with a mass driver system, you just electromagnetically fling loads of the material to Venus. In fact, it may eventually be the case that we build mass drivers on many bodies in the solar system to move materials around.

An alternative to securing the water which is much faster is to simply crash an icy moon into Venus in a controlled fashion. This is harder, but also surprisingly possible through using the gravity of bodies such as Saturn and its moons to move large objects around.

Then you need the oxygen. This can come from our frozen carbon dioxide oceans readily either by chemically releasing it or using algae or a similar bioengineered method taking advantage of photosynthesis.

The last major problem is Venus's slow rotation. One approach to this would be to speed the planet up, and there are theoretical ways to do that, but it would seem to make more sense to just simulate a 24 hour day. Birch suggests that we use a soletta, a kind of rotating mirror in polar orbit to create the illusion of a day. Alternatively, solar mirrors can both shade the lit side of Venus and reflect light to the dark side as needed to create a suitable day.

While all of this may seem beyond reach, at least in theory it's actually something we could do right now. Birch lays out in his paper that we could begin colonization of the atmosphere and terraforming efforts in 2030 and have a fully habitable second earth by 2250. It would be difficult and expensive, there's no doubt of that, but it is doable and may not be so expensive as we expand out and begin colonizing other areas of the solar system at the same time. Especially if Elon Musk's plan for Mars comes to fruition, a big part of that is that the entire solar system becomes accessible.

So both colonizing Venus' atmosphere and eventually terraforming are possible and perhaps even advantageous. And with all the buzz surrounding Elon Musk's bold plan to colonize Mars, I hope the idea of colonizing the solar system catches fire and some day Venus too may also be a self-sustaining home for humankind.