Category: alien life

Will Humanity Achieve Interstellar Travel And Find Alien Life?

“All of this, together, points to a picture where a spacecraft or even a crewed journey to the stars is technologically within our reach, and where the discovery of our first world beyond the solar system with possible life on it could occur in a decade or two. What was once solely in the realm of science-fiction is quickly becoming possible due to both technical and scientific advances and the thousands of scientists and engineers who work to apply these new technologies in practical ways.

On February 5 at 7 PM ET (4 PM PT), Dr. Bryan Gaensler, director of the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto, will be delivering a public lecture at Perimeter Institute on exactly this topic. Titled Warp Drive and Aliens: The Scientific Perspective, it’s available to watch from anywhere on Earth, and I’ll be following along with a live-blog in real time…”

For as long as we’ve been looking up at the stars, we’ve wondered whether it will ever be possible to travel to one of them, and to perhaps discover another planet where life has taken hold. What’s been a mere sci-fi dream for humanity for most of our history at last, with 21st century technology, has the possibility of becoming a reality. 

Later today, Dr. Bryan Gaensler will be delivering a public lecture at Perimeter Institute that will be webcast in real-time all over the world, and you can follow along with my live-blog of his talk in real-time, too!

Is Alien Life Hiding Beyond Earth 2.0?

“It may be the case that life is rare in the Universe, in which case it will require us to look at a lot of candidate planets — possibly with very high precision — in order to reveal a successful detection. But if we search exclusively for planets that have similar properties to Earth, and we restrict ourselves to looking at parent stars and solar systems that are similar to our own, we are doomed to get a biased representation of what’s out there.

You might think, in the search for extraterrestrial life, that more is more, and that the best way to find life beyond Earth is to look at greater numbers of candidate planets that might be the Earth 2.0 we’ve been dreaming of for so long. But non-Earth-like planets could be home to life that we’ve never considered, and we won’t know unless we look. More is more, but “different” is also more. We must be careful, as scientists, not to bias our findings before we’ve even truly started looking.”

If we want to find life elsewhere in the Universe, it only makes sense to look at our own world, where we know it was successful, and to try and find other worlds similar to our own. But that absolutely cannot be the only thing we do, or the only inhabited worlds we’ll even have a chance at finding are the ones similar to our own.

We have many good reasons to favor or disfavor the probability of finding life on a variety of planets and moons out there in our galaxy, but the real truth of the matter is we don’t know how common or rare life is. We don’t know how common or rare a huge variety of processes are, or even whether life is more likely to arise under conditions very different from those we find on our own planet.

It’s possible that Earth-like worlds are the best bet for life in the Universe, but don’t count out the non-Earth-like worlds without looking. Here’s what everyone hopeful for discovering alien life should keep in mind as we search the galaxy.

Ask Ethan: Would Life On Earth Be Possible If We Were Anyplace Else In The Galaxy?

“[W]hat would happen if our solar system had formed a little farther up the arm of the galaxy? What would happen if we were at the tip of the arm? What if, theoretically, instead of the humongous black hole in the center of our galaxy, our solar system was there? Would there be major climate difference[s]? Would we be able to survive?”

We can all agree that what’s happened here on Earth is something that’s extremely special in the Universe. Our planet has developed and sustained life on it for over four billion years, and that life continues to thrive even at present. Our planet has been fortunate enough to have stable enough conditions and mass extinction events that have never eliminated 100% of the life that exists on our world. But how ‘special’ does that make Earth, that this is our story? Do we need a large Moon? A solar system like ours? A star like our Sun? And do we need to be located at our present location in the galaxy, or would many places be just as good?

It’s a tough question to answer with certainty given the paltry evidence we have, but we can certainly examine these questions in-depth. Let’s do exactly that for this edition of Ask Ethan!

No, NASA Did Not Find Even ‘Hints Of Life’ On Enceladus

“So if it happened here on Earth, why couldn’t it happen on another world as well? The answer, of course, is that it could happen there, and it could have happened there billions of years ago. Life could very easily be surviving and thriving beneath the icy crust of this distant, Saturnian moon.

But that’s not what we found. We didn’t find molecules that indicate they’re the products of life processes; the molecules we found are the raw ingredients for life. There’s a tremendous difference between the two, and finding raw ingredients on Enceladus no more means there’s life on that world than finding sugar, flour, eggs, milk, and butter in your house means there’s a successfully baked cake there.”

Did you hear about the news on Enceladus? For the first time, on a world beyond Earth, we’ve detected the trifecta of combinations:

-a liquid water ocean,
-an undersea source of heat and energy,
-in combination with the presence of the raw ingredients necessary for life.

Many are speculating that this makes Enceladus a surefire winner in the search for the first life that has an origin beyond Earth. But that’s speculation, not science.

The truth of the matter is that finding the ingredients for life, which are everywhere, is a very different prospect than finding the products of life, which are nowhere to be found in these plumes. These are not the hints of life we were hoping for.

Rocks on mars may contain evidence of life from 4 billion years ago

Iron-rich rocks on Mars have been found which were formed in a lake bed at the Jezero Crater delta during the Noachian and Hesperian periods of Martian history 3-4 billion years ago. During this period there was an abundance of liquid water which could have supported life. Due to the lack of tectonic plates on Mars, these rocks are far better preserved than those on earth of the same age.

Scientists aren’t expecting to find fossils of animals or anything like us but more likely single called organisms known as microbes. This is still an exciting prospect for us to potentially study how alien life on other planets might start out.

Life orbiting our closest star?

A planet has been found orbiting in the habitable zone of the closest star to earth, 4.2 light years away, named Proxima Centauri. The exoplanet, known as proxima b, has the mass of 1.27 earths but because of the shape of its orbit, the chances of it harbouring liquid water are fantastic. This vastly improves the chances that the planet sustains alien life.

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Behold the Dyson Sphere

Dyson sphere is a hypothetical mega-structure that completely encompasses a star and captures most or all of its power output.

Over the years many variants have been explored:

The simplest such arrangement is the Dyson ring, in which all ‘energy harvesting structures’ share the same orbit.

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Add multiple Dyson ring structures and you will get a Dyson swarm.

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Now what if you didn’t like a consistent orbit for your structures, you could employ a solar sail to continuously modify its orbit( called a statite ).

Such an arrangement would be known as a Dyson Bubble

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Then there is the fictionally popular version – The Dyson Shell, where a uniform solid shell of matter just encapsulates the entire star.

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And many many more. But you get the gist.

Could there be Dyson Spheres out there?

When scientists were monitoring the brightness from some stars, they
found that it fluctuated in some odd ways like so:

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                          Brightness v/s time for KIC 8462852

It is common for such dips to occur since when a planet eclipses a star, there would a drop in the brightness observed from the star.

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                       Brightness v/s time for a binary star system

But what was inconsistent is the duration and period of occurrence of these dips.

Although the main line of rationale remains as asteroid impact remnants or interstellar collisions causing these aberrations in data.

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But to say that these could the signs of an alien civilization does remain to be the more entertaining interpretation.

Great Question. Thanks for asking !

** For more information. check out this TED talk

Enceladus – Life in our solar system?

Enceladus is Saturns icy moon that measures approximately 504km in diameter, about a tenth of the size of Saturn’s largest moon Titan. Almost completely covered in ice, this moon could potentially harbour the same type of life-sustaining chemical reactions found in deep sea hydrothermal vents here on Earth.

In 2005, NASA’s Saturn orbiting Cassini spacecraft spotted geysers of water and ice erupting fro fissures near Enceladus’ South Pole. Scientists believe they originate from a great ocean beneath the shell of ice. This ocean manages to stay liquid because the gravitational force exerted by Saturn is so intense that it twists and stretches the moon generating internal heat.

In October 2015, Cassini went on a dive through one of the plumes passing within just 39km of Enceladus’ surface. A team of scientists led by Hunter Waite analysed the observations made by the spacecraft. They discovered that the geysers contain between 0.4%-1.4% molecular hydrogen (H2) and 0.3%-0.8% carbon dioxide (CO2). These are being produced continuously by reactions between hot water and rock near the core of the moon. Some of the most primitive metabolic pathways found in microbes at deep ocean hydrothermal vents involve the reduction of CO2 with H2 to form methane (CH4) by a process known as methanogenesis.