Is there life beyond Earth’s Solar System?

Where are we right now on our journey to locate possible life (including intelligent life-forms) outside our Solar System?

Figure 1: Man meets Milky Way. (Source: European Southern Observatory)

Ever wondered whether there was life among the stars in the night sky, whether that life-form, like us, is staring into the empty yet shining prospect of outer space. This question of whether there was life among the stars and abyss has been a controversial topic for centuries and I believe that the answer to our question is slowly coming into our grasps as society progresses into a golden age of science and technology.

Various world-renowned programs and industries have been on this journey to see if we really are alone in the universe.

One of the ‘ET’ (Extra-terrestrial) programs that explored this topic was SETI Institute, which conveniently stands for Search for Extra-terrestrial Intelligence Institute. This Non-profit Organisation graciously accepts private donations from many other organisations which is then used to fund their search for Extra-terrestrial life.

However, despite their on-going use of antennas to detect alien communication attempts has been going on for 60 years, they have yet to collect any solid evidence from ‘aliens’ in the form of radio-waves. They also have noted that despite attempting to receive signals from ‘aliens’ they do not attempt to broadcast any. Despite the lack of evidence there is no conclusive evidence on anyone’s side, so they could still exist? Or they could not?

Aforementioned, SETI has attempted to search for intelligent civilisations in the cosmos for 6 straight decades and as of recently developed from just detecting radio-waves to experimenting with other techniques, one that arose due to an ‘Optical-SETI’ experiment. The experiments saw the use of a piece of Russian technology dating back to the 1930s called Photomultiplier Tubes or PM tubes, these tubes are incredibly fast and exceptionally sensitive to light.

Figure 2: An Optical SETI Telescope.

The PM tubes sensitivity when tested yielded results that were of remarkable sensitivity, the test conducted was in short, exposing the PM tube to a small quantity of photons which they would be able to detect, despite only being shown it for a billionth of a second.

Figure 3: The Amperex PM-2412B (a simpler PM tube used in gamma cameras).

However, despite their sensitivity they are remarkably able to differentiate what signals are really from aliens and what are from the stars, they do this thanks to a certain design in the telescope which break the observations of light into nanosecond intervals, in relative terms that’s 1 second equals 1 billion nanoseconds, meaning a nanosecond would have definitely finished before you can respond to well, anything. Conveniently enough a star like the sun would only emit one or less photons in a nanosecond, so, if the PM tube picks up a signal with a higher number of photons (like 10 photons), there’s bound to be some sort of interest there, perhaps even the exciting promise of another intergalactic civilisations.

Regardless of this notion, we won’t really find any actual lifeforms if the lifeforms themselves aren’t intelligent enough or have found no use in using light. In order for the PM tube to locate life in the vastness of space, there must be an actual object or individual sending very short pulses of light.

To efficiently detect this ‘out-of-this-world’ light it must be lasers emitting the light, in other terms monochromatic light which produce light in a narrow range of wavelengths, which are easily detected by the PM tube. On the other hand, if photo-flashes or white light was shone into outer space, it will be difficult to actually detect that light.

Luckily, the Optical SETI detector that was developed by Alan Holmes eased the restriction of the former PM tube, proving to be useful as it was a lot cheaper and did not require the beams to be short pulses, instead it didn’t matter how the monochromic light was shone anymore, it just mattered whether the light is actually present. With this technology the SETI institute is able to more efficiently answer the controversy surrounding alien-life.

Similarly, a renowned agency also has taken a keen interest in ET life, this agency is non-other than NASA. NASA, an acronym for The National Aeronautics and Space Administration, has found some interesting ‘evidence’ on their Mars expeditions. Although not what we hoped to find, NASA collected evidence for less intelligent beings, also known as microbes, like bacteria, but also some indicative evidence which may show evidence of intelligent lifeforms in outer space.

During their 1976 Mars expeditions, NASA’s Viking Mars landers detected and analysed radioactive methane gas which hinted that something in the soil was metabolising nutrients and releasing radioactive methane as a by-product, these seemingly organic molecules hint at some sort of lifeform, even if they be microbes, for some its reassuring to know that we aren’t alone in the universe.

Figure 4: The Gale Crater, Mars and the predicted landing point of the curiosity rover (circled in black) in August 2012.

The recent, 2019 NASA Curiosity Rover discovery found that the Gale Crater on Mars contained 0.16% oxygen gas, something that could come from abiotic (‘non-living’) or biotic factors (‘living’). Although, scientists have already essentially crossed-out abiotic factors, due to firstly, CO2 taking too long to break apart in the atmosphere to create that much oxygen. And crossing-out, H2O from the drawing board because there wouldn’t be much oxygen in the atmosphere to actually create the oxygen gas because most of it is either frozen or has too much salt concentration or even just sunk into Mars to form clay.

Figure 5: Mars Seasons and their respective oxygen levels (both predicted and observed).

Additionally, over the years, scientists had found that the hydrogen from water molecules didn’t simply float into space, but rather just sunk in the ground to form clay, this was speculated and confirmed by Scheller and her team using atmospheric observations by NASA’s Maven Mars Satellite and the European Space Agency’s Mars Express craft.

Their observations consisted of the knowledge that the Deuterium (proton and neutron in the nucleus) to Hydrogen (proton in nucleus) ratio was too low. There was less Deuterium in the air than there should be if all the hydrogen escaped in space, because the less hydrogen in the air the more deuterium there would be, but that wasn’t the case with mars, Deuterium hadn’t taken over the number of hydrogen atoms, proving that the water didn’t evaporate. This led way to further research and discovery of the fact that the water had become clay and sunk into the Martian surface.

Furthermore, the liquid water on Mars was found to be toxic to humans and therefore not drinkable due to the brine (high salt concentrated water) or water having too much perchlorates (which are toxic to humans). Worry not, if we were to go to Mars there would be plenty of fresh unsoiled frozen water on the poles of Mars, this water from Mars’ glory days where like Earth the conditions were prime for water to cover the surface of Mars.

The fact that there was water on Mars a proves that life could have inhabited the red planet, after all water is from what we know a building block of life. Although, for now we can only know that there is sadly no definite evidence pointing to life.

Figure 6: The four main telescopes used by Breakthrough Listen are scanning nearby stars and galaxies for any radio or laser messages beamed at Earth. (Source:

To add to these, in 1977 the unexplained event that was received to a radio telescope at Ohio State University, which was revealed to be an unusual pulse of radiation from around or near the Sagittarius Constellation. The signal which was around 37 seconds long was within the band of radio frequencies of which cannot be used internationally on Earth. To further this, the radiation or signal cannot be told to have come from natural sources in space which would occur in a much wider frequency. So, the only explanation scientists could derive was that either it was a massive astronomical event or, the more exciting possibility of aliens using a very powerful radio transmitter, the occurrence has yet to be explained.

Figure 7: Stromatolite Rock Structures are fossilised microbes similar to that of which can be found on Mars.

Finally, NASA scientists announced in 1996 that they had discovered something that seemingly represented fossilised microbes in a lump of Martian rock which had fell onto Earth in the form of a meteorite. The meteorite (code named ALH84001) was found on Antarctica in 1984 has been assumed to have been wondering in space after being kicked of Mars in a collision for 15 million years.

The rock when under cautious observation was told to have contained organic material and small traces of magnetite (sometimes found in Earth bacteria), and also signs of nanobacteria when put under the electron microscope. Since then however, in an attempt to create controversy much evidence has been brought up in an attempt to disapprove the evidence of life.

Furthermore, the reason for the excitement for microbes is that microbes are normally what comes into life first, and it is essential for the planet to sustain more complex lifeforms. If I were to put this into Earth’s development, the first form of life on this planet were the microbes and simply put they are what made Earth habitable. This due to the photosynthetic bacteria using light energy from the sun to ingest carbon dioxide and release oxygen to make aerobic species who do not use sunlight to get energy possible, these tend to be the more complex life forms.

The captivating things about looking into Mars and its possibility of having life in the past, is that it shows that Earth is not the only habitable planet to have existed, if Mars was able to support life, then its safe to say that many other planets inside or even outside our solar system could support life as well.

Even though, they may not be as intelligent as humans have gotten to be with their extensive amounts of resources, the habitability of other planets could indicate life, life that could still be developing on other planets, and hopefully someday we could make contact with other interplanetary species other than those here on Earth (like the scene from ET, just a bit more realistic).

Figure 8: ‘ET’, a 1982 popular film.

Referencing (APA6)


· (Figure 1) — Horálek, P. (2019). Man meets Milky Way. European Southern Observatory. accessed on the 5th July 2021.

· (Figure 4) Destination Gale Crater in August 2012. (2012) accessed on the 7th July 2021.

· (Figure 2) Optical SETI at Harvard. (2004). accessed 5th July 2021.

· (Figure 3) Detection & Imaging Tubes. (n.d.). accessed on the 5th of July 2021.

· (Figure8) Movieclips Classic Trailers. (2011). accessed on the 11th July 2021.


· Is there life on other planets?. (n.d.). planets/#:~:text=Among%20the%20stunning%20variety%20of,show%20signs%20of%20potential%20habitability accessed on the 5th July 2021.

· Carl S and Frank D. (1997) The Search For Extraterrestrial Intelligence. accessed on the 5th July 2021.

· Seth S. (n.d.). Optical/Laser SETI. accessed on the 7th July 2021.

· Jeffrey K. 2021. Mars Has Much More Water Than Previously Known — But There’s a Catch. accessed on the 9th July 2021.

· John P. (2006). Top 10: Controversial pieces of evidence for alien life. accessed on the 9th of July 2021

· Daniela H. (2015). What It Would Take To Drink The Water On Mars. accessed on the 10th of July 2021.

· Alvin P. (2004). History of life on Earth is largely microbial. accessed on the 11th of July 2021.

Image and Report (Combined Use)

· (Figure 6) — Daniel C. (2020). How big money is powering a massive hunt for alien intelligence. accessed on the 6th of July 2021.

· (Figure 5) Lonnie S. (2019). With Mars Methane Mystery Unsolved, Curiosity Serves Scientists a New One: Oxygen. accessed on the 7th July 2021.

· (Figure 7) Michael M. (2019). Fossilised microbes from 3.5 billion years ago are oldest yet found. accessed on the 10th July 2021.




Love podcasts or audiobooks? Learn on the go with our new app.

Recommended from Medium

Eclipses on Earth

What Was the Chandrayaan-2 Mission?

Exploring the World’s First Space Hotel

Orbital mechanics and risk

Fifth Batch of Starlink Satellites Launched by SpaceX; MakesTotal to 302 Satellites

Send in the Bots

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Heshan Dewapakshage

Heshan Dewapakshage

More from Medium

What exactly is Orientalism?

Predictions for Foxtel in 2022

The Stupidest Rule in the NFL

Everything is a Wave.