Before humans and animals and even plants dominated the Earth, it was full of prokaryotic life. Extremophiles are types of prokaryotes that can not only survive, but thrive in extreme environments.
There are a lot of barriers to humans living in space. But two of the problems may have an innovative solution involving fungus. A major problem is radiation. Once you get farther away from Earth, Earth’s atmosphere and magnetic field can no longer protect from harmful radiation from the Sun. According to NASA, an astronaut […]
Based on various calculations and estimations made by scientists all over the world, there is a very high probability that aliens (i.e. life elsewhere in the universe) exist. However, we have never encountered any tangible or irrefutable evidence of aliens. This contradiction is called the Fermi Paradox.
One possible explanation for this paradox is that while life is likely to occur in other places, it is unlikely based on the physical and time scale of the universe that two separate civilizations would cross paths. This suggests that throughout the life of the universe, there have been many different developments of life in different places, but because the lifespan of these civilizations are relatively short, different life developments never meet or see any evidence of each other. Another factor to consider is that while life may be likely to develop in the universe, intelligent life may be much more rare. This would mean that the lack of evidence of extraterrestrial life is not because there isn’t life, but that the life that exists has no way of providing such indications of its existence.
Overall, the fermi paradox is one of the most interesting concepts to consider when thinking about the universe. While we have no irrefutable proof of aliens currently, that doesn’t mean we won’t sometime in the relatively near future.
The word extremophile comes from the Latin words extremus (meaning extreme) and philia (meaning love). An extremophileis an organism with the ability to survive, or even thrive, in an environment that we as humans would consider extreme. These organisms are some of the oldest species to exist on Earth. Some of them date back to more than 40 million years ago. Because of their ability to survive harsh environments, these creatures are some of the most abundant on Earth.
One of the main types of extremophiles is thermophiles. These organisms can survive excruciatingly hot temperatures. Another type is psychrophiles, which can survive very cold temperatures. Two other less known types are halophiles (salt loving) and acidophiles (high pH loving).
Because of extremophiles’ ability to survive in extreme environments, many people believe that they could exist on other planets. For example, a thermophile could exist on Venus (where a human could not) because it can withstand the excruciating temperatures.
The Drake equation investigates the likelihood of intelligent, communicating life existing on other worlds in our galaxy. But what if life could easily exist on other worlds, and there was life in every solar system around us? What could this potentially mean for us? First, we must consider the fact that the closest star to our sun, Proxima Centauri, is 4.25 light years, or 40 trillion kilometers, away from us. The Parker Solar Probe, which is the fastest spacecraft humanity has constructed, will travel 690,000 km/hr at its fastest point. If a spacecraft traveled at this speed the entire distance from Earth to Proxima Centauri, it would still take over 6.6 thousand years to reach it. From this, I ask the question: Would it have any significant consequences to us if life outside of the solar system existed, considering the fact that it would take so long to travel to other solar systems anyways?
Another interesting thing to think about is what those aliens might look like. They could have completely different systems for sensing and interacting with their environment, and might not even need water or be carbon based life forms.
A rendition of what life might look like on other planets (ScienceFocus)
In 1977, the Voyager I and Voyager II spacecrafts were launched into space to study the outer solar system. After conducting flybys of the planets in the outer solar systems, the Voyager spacecrafts continued to travel away from Earth, and will eventually travel out of our solar system. With this knowledge, golden records were placed on both Voyager spacecrafts to give any extraterrestrial intelligent species information on what Earth was like at the time of their launch. The records themselves contain a variety of sounds, including the sounds of waves, wind, animals, thunder, spoken greetings in 55 languages, and a variety of music including classical, folk, blues, rock, and electronic music.
The cover of the Voyager Golden Record (Wikipedia)
The record also contains 115 images, which include images of DNA and human anatomy, images of landscapes, animals, and plants on Earth, and images depicting a wide range of cultures. Among other things, the cover of the plaque contains instructions on how to listen to the sounds and view the images on the record, as well as a map showing Earth’s location relative to 14 nearby pulsars and their respective periods. These plaque serves to give any extrasolar civilization that might come across the Voyager spacecrafts in the future an idea of what Earth was like in 1977, as well potential means of locating Earth via the pulsar map.
Nucleobases are the building blocks of DNA and RNA. There are five total nucleobases (adenine, thymine, cytosine, guanine, and uracil) and three of the five have been found in meteorites. Recently, the last two nucleobases have also been identified. This suggests that nucleobases could have been sent to Earth from meteorites or dust and could […]
This weird picture is set to resemble a massive planet scientists have just discovered. This planet is about nine times the size of Jupiter, and its in its very early stage of formation. This star was discovered through the use of a Hawaiian telescope, and it was discovered floating “unusually far” from its parent star. Evidence from this planet suggests this is the earliest in formation we have ever observed a planet at. This planet is also only 508 light years away from us. Although that seems like a huge amount, in astronomical terms, that is actually very close.
This planet is approaching its maximum size to be considered a planet. If it continues to grow, it will soon be called a brown dwarf. This is the classification for something of intermediate size between a planet and a star. Planets like this, in the process of formation, have only been observed around one other star prior to this. This planets formation is also challenging the previous conceptions of scientists on the birth of planets, this new data is causing scientists to reconsider their theory’s.
The Drake equation, as we know, has served to estimate the amount of possible intelligent life in the universe. Up to this point, we only know of one, us. We were previously searching for life by looking for radio signals. But obviously, we have not had success with this. Despite this, a new method of searching for life has arose, and scientists and astronomers are optimistic this could better lead us in the search for other life. We now are beginning to search for “biosignatures“, which are signs of life, despite the fact that the planet may have not developed any intelligent life yet. This may come in the form of Methane in the atmosphere, or other signs of life.
This allows us to split the Drake Equation, having one equation for biosignatures and one for technosignatures(technological signs of life). This is helpful because we know from our own planet that the formation of intelligent life takes an insane amount of time, and we’re much much more likely to just find life than intelligent life, and any discovery is very useful.
When I enrolled in this class at first, I knew that quite obviously the class would be focused on learning more about the Solar System (as the title of the class was quite literally “The Solar System’). However, I think that what we covered in this class did help me learn much more about the solar system and universe than I had at first anticipated, with interesting and elaborate connections to other scientific fields as well.
Particularly, I found learning about the environment and geography of each planet very interesting. For example, learning that Pluto may have an ocean core was shocking and at first hard to visualize in my mind. Then discovering how the planet actually had all these really unique and unexplainable features, like ice mountains and active tectonics of some sort, made me appreciate the work of NASA and other space agencies more. I see that the drone missions weren’t there just to take cool pictures and leave, rather they served a distinctive purpose and where able to give us on Earth much greater insight into the solar system, knowledge that could be quite useful to our understanding of the world. I also walked away with respect for those on the mission and the hard work, vision and discipline they had in order to achieve this.
I also enjoyed learning more about how other branches of science play into astronomy and how, like mathematics, physics, engineering, and biology. I think this class did a good job of not only explaining exactly how these connections work (like in the physics / asteroid worksheet) but also why they are important to facilitate and the benefits of doing so. I personally think thats a good message and agree that in order to discover some of the truths of the Universe you have to be a bit creative and use all of the knowledge and tools you can get.
Ultimately, I enjoyed this class and learning not only more about the solar system but also other scientific fields as well. I thought that the engagement between the two was interesting and affirming, and I look forward to carrying this new perspective with me and applying it in the future.
