Content in a flash
2. Exoplanets discovery – How are exoplanets discovered?;
3. Exoplanets identified – Numbers and examples of exoplanets identified till now;
4. Exoplanets discovery: Ubiquitous exo-life – The recipe for life is found in every corner of the universe;
1. Exoplanets discovery > stars
In a previous article we have looked first at how a new model of the universe points to an infinite reality leading us to logically infer that the number of alien civilisations – which is already extraordinary high within our universe – may be multiplied by infinity.
In a second article, Hyperspace, we reviewed how additional dimensions may confirm the new model of the universe reviewed previously and may offer near godlike feats to intelligent civilizations advanced enough to harness their power, making them able to visit us thanks to and/or through additional dimensions.
Let us now zoom in one level down and let us investigate the existence of those objects in the universe that back up the calculations leading to the astonishing likelihood of aliens and the unbelievably high number of alien civilizations: Exoplanets.
With exoplanets are intended planets that orbit other stars beyond our sun.
We know that in the Milky Way alone, our galaxy, an estimate of 100 to 400 billion stars exist. According to the same source, NASA, the number of Exoplanets in the Milky Way galaxy alone outnumbers the amount of stars, with an estimate hitting “trillions”:
Based on observations made by NASA’s Kepler space telescope, we can confidently predict that every star you see in the sky probably hosts at least one planet. Realistically, we’re most likely talking about multi-planet systems rather than just single planets. In our galaxy of hundreds of billions of stars, this pushes the number of planets potentially into the trillions.” – Source.
This is rather intuitive, since 8 main planets orbit the Sun in our Solar System, and our star is a pretty standard one.
2. Exoplanets discovery – How are exoplanets discovered?
Until recently, the existence of exoplanets was not known simply because we did not have the technology to observe them. Science is the usual doubting Thomas, while those of us who intrinsically believed in life beyond our planet were already obviously certain of the existence of planets that harbour life without additional evidence.
What allowed humanity to be totally certain of exoplanets? Telescopes, especially those launched in space. From the retired Kepler that observed 530,506 stars and discovered 2,662 exoplanets over its lifetime, to NASA’s Transiting Exoplanet Survey Satellite (TESS), from MOST Canadian space telescope to the world famous Hubble, these instruments have built the first bridge between Earth and outer space.
While the general public assumes that astronomers possess advanced tools able to elaborate the Exoplanets discovery at the snap of fingers, the truth is that our dear scientists have to rely on rather “rudimentary” tools and be smart about the discovery process.
This is how a space telescope identifies the existence of an exoplanet: as soon as a planet crosses between the telescope lens and the star around which the planet is orbiting, the star’s brightness dims by one one hundredth of a percent, which is 0,0001%. In this way scientists learn about the planet size, mass and the orbit’s length.
With super sensitive light detectors and space based telescopes, astronomers are looking for the dimming of light caused by otherwise undetectable planets crossing in front of distant stars.
The vastness of space makes this an enormous task, so instead of a random search, NASA has focused the Kepler’s telescope on a specific path of the Milky Way galaxy with 150k visible stars. By staring a long time at the same group of stars they are much more likely to achieve their mission in finding Earth’s twin.
There are 2 criteria that astronomers use for the Exoplanets discovery
1) When they transit in front of a star making its brilliance diminish and
2) If the star wobbles because then it means that a planet is circling around it. This second factor helps in quantifying and assessing the planet’s mass and size.
It is hard to capture a planet crossing in front of its star since many planets have tilted orbits and do not pass in front of their star from our point of view (telescope’s point of view).
As you can see, the level of complexity to discover an eXoplanet is very high. As a consequence we should celebrate each single discovery big time. The amount of work behind each discovery is massive.
Despite all these difficulties, there has been an avalanche of findings of smaller planets compared to larger planets and this is a great news since planets similar to the size of Earth (smaller compared to Jupiter, Venus, Saturn, Neptune …) are more likely to host life, since Earth is the one planet we know that has life. If we find another planet with similar features to Earth such as a smaller rocky planet with liquid water then it too may sustain life.
Any smaller and it may not have enough gravity to hold on to an atmosphere, much larger and it might be made of gas or could have other unknown but deadly conditions. It is the presence of liquid water (made possible by the right temperatures) to determine the possibility of life since water is such a crucial condition for life. The popular Goldilocks zone refers to planets whose surface temperature is between the freezing point and the boiling point of water, making their atmosphere a habitable zone.
3. Exoplanets identified
In 1995 Pegasi B aka Dimidium was the first planet to be discovered outside of our solar system and from there we entered a new era proving that Earth-like planets could exist outside in the universe.
Specifically, Pegasi B is a gaseous and a planet as large as Jupiter that is very close to its star 51 Pegasi; it shook our knowledge of the universe, teaching us that planets over time move closer and closer to their star.
Exoplanets discovery, the numbers:
As of the 24th of January 2023 there are 5,241 exoplanets confirmed in 3,915 systems with 853 systems having more than one planet.
Does this mean that these about 5,000 exoplanets are all there is?
First of all, so far almost all of the exoplanets detected are within the Milky Way alone. To put things additionally into context, according to Geoffrey Marcy, Director of the Space Laser Awareness institute, we can safely assume that about “1 in 5 Sun-like stars have an Earth-like planet in the habitable zone”; and that is a rule applicable to the entire universe.
Referring back to NASA’s estimate of the existence of stars in our galaxy being between 100 and 400 billion, we can calculate that there are likely to be 20 to 80 billion potentially habitable earth sized planets in the Milky way alone. Basically, we have discovered a minuscule fraction of all potentially habitable planets in our galaxy. Other intelligent beings are just out there waiting for us to discover them – and the other way around applies to many of us – : the existence of aliens is mathematically sound.
All this without considering the existence of rogue planets; hard to believe but these planets are called “rogue” because they do not orbit any star. We are not sure if it has a disproportionately large orbit or if it is a rogue planet to all effects, however this type of description certainly fits “two” planets that we believe being the same:
the missing 9th Planet X of our solar system and Nibiru. More on this on an upcoming article dedicated to this topic.
So, if we were offered a chance to travel to an exoplanet by a generous Elon Musk type of billionaire, where would it be smart to head to without spending our lifetime on a spaceship (excluding the option of using stasis pods)?
Until January 2023 the nearest exoplanet was Proxima Centauri B being 4,2 light years away. We have since discovered a closer one: Wolf 1069b. Wolf 1069b is 1,3 times the size of Earth, orbits its sun, a red dwarf, at the equivalent of one-fifteenth of the separation between the Earth and the Sun and is, 31 light years away.
4. Exoplanets discovery: Ubiquitous exo-life
“Unless there is something extraordinarily miraculous about our solar system or our planet, then life has got to be extremely commonplace. There has got to be large numbers of worlds with life and some of them will have cooked up intelligent life.“
– Seth Shostak, Senior Astronomer SETI
In 1953 researcher Stanley Miller proved in a lab experiment just how easily life on Earth got its start. He combined water with hydrogen, methane and
ammonia, components of the Earth’s early atmosphere. Then, he zapped his solution with an electric charge to simulate lighting. His results shocked the world. Miller had created organic molecules called amminoacids, the protein building blocks of all living things.
Galactic probes have now found the ingredients in Miller’s experiment throughout our solar system. More on this in the second part of this article.
We now see these headlines regularly: “Astronomers have identified a group of planets outside our solar system where the same chemical conditions that may have led to life on Earth exist.” Remember, we have just put our nose outside of our main door.
And this is just by maintaining the wrong assumption that life need the same conditions that plants, animals and humans require on Earth.
Ready to challenge this assumption, biologists started combing Earth’s darkest and coldest places and to their surprise they found living, breathing creatures. Biologists call these organisms extremophiles. Some do not need light or oxygen, others survive under tremendous atmospheric pressure. It seems life can turn up practically anywhere. Organisms have been found in Antarctica at 68 degrees below zero and 6 meters below ice.
This is confirmed by Dr Clark R. Chapman, senior scientist and astronomer, Department of Space Studies at the Southwest Research Institute’s Boulder, Colorado, “Biologists have been increasingly discovering simpler forms of life that live in very cold temperatures, very high temperatures, very great pressures, even in places where there is sort of a high degree of radiation. It turns out that life is able to live in a much wider variety of environments on our own planet than we used to think.“
This means that with rudimentary tools, extremely conservative requirements and for a very short time we have been looking to detect signs of life beyond our planet and despite all these challenging factors we see life swarming on other planets.
To be continued…
What you can expect from the next and final section: In this first section we concentrated on the Exoplanet side of things. In the continuation of this article we will shed light on the Exolife, meaning: is life springing out of other planets as well or only on Earth?